Tuflow - User contributions [en]

Advection Dispersion Modelling

2026-03-24T08:17:41Z

Tuflowduncan:

=Introduction=
TUFLOW’s Advection Dispersion (AD) functionality is an extension of the TUFLOW Classic/HPC engines available within the TUFLOW CATCH module. It adds to the hydrodynamic capabilities of TUFLOW Classic/HPC by simulating depth-averaged, two and one-dimensional constituent fate and transport. An example of such a constituent might include salinity. Both dissolved and particulate constituents can be simulated. TUFLOW AD takes depth and velocity fields computed by the TUFLOW Classic and HPC solvers and uses this information, together with initial and boundary conditions, to simulate the advection and dispersion of user-defined constituents.

TUFLOW AD is specifically oriented towards such analyses in systems including coastal waters, estuaries, rivers, floodplains and urban areas. The AD functionality is discussed in detail in the [https://docs.tuflow.com/classic-hpc/manual/latest/ TUFLOW Manual - Chapter 9].

=Model Development=
==Setting Up a New Model==
The steps below describe the process for setting up a TUFLOW AD model. It is assumed that the user is familiar with TUFLOW Classic/HPC and that the folder structure for TUFLOW has been setup with all required files. The user should run the TUFLOW Classic/HPC model without the AD functionality first to make sure that it is appropriately configured and stable.

<ol>
<li>Create a TUFLOW AD control file with the extension .adcf
<li>Use a text editor to create an empty .adcf file and save it to the “runs” folder.

<li>Set up the AD global database (.csv file).
<li>Set up the TUFLOW AD global database in the “bc_dbase” folder which defines the constituent of interest and a number of characteristics, for example the decay rate and dispersion coefficient. The resulting file should look similar to the below: 
[[File:EG17 AD Consit 001.png]] 

<li>In the .adcf file use the "AD Global Database" command to set the location of the global database as follows. <tt>AD Global Database</tt><tt> == </tt><tt>..\bc dbase\my_ad_global_dbase.csv</tt>

<li>Set up the boundary condition tables (.csv file(s)) to define the time-varying constituent concentrations at any input boundaries.
<ul><li>Set up the constituent boundary condition table(s) in the “bc_dbase” folder. For example in the below, the time-varying concentration of constituents Conc_AD1 and Conc_AD2 are set: 
[[File:EG17 conc 001.png]] </ul>
<li>Set up up the boundary condition database (.csv file)
<ul><li>Set up the boundary condition database in the “bc_dbase” folder that references the tables set up in the previous step. 
[[File:EG17 AD 001.png]] 
<li>In the .adcf file use the "AD BC Database" command to set the location of the bc database as follows. <tt>AD BC Database</tt><tt> == </tt><tt>..\bc dbase\my_ad_bc_dbase.csv</tt></ul>
<li>Setup up TUFLOW to activate the AD functionality (.tcf file)
<ul><li>In the .tcf file use the command "AD Control File" to set the location of the adcf and activate execution of the AD functionality as follows. <tt>AD Control File</tt><tt> == </tt><tt>ad_run.adcf</tt></ul>
<li>Run the model
<li>Run TUFLOW as normal. The AD functionality will be utilised and appropriate constituent result output files written.

</ol>

==Example Models==
Example TUFLOW AD models, including settling and decay, are available via the [[TUFLOW_Example_Models#Advection_Dispersion | TUFLOW Example Model Dataset]].

= Common Questions Answered (FAQ) =

== How can the Advection Dispersion functionality be used to determine the time of concentration in a 1D-2D TUFLOW model? ==
The Advection Dispersion functionality can track particles and determine the time of concentration by simulating how a particle of water travels from an upstream to a downstream location. However, the AD functionality is only available for 2D domains and cannot directly operate within a 1D channel.

To utilise the AD functionality in this case, the 1D channel would need to be converted into a 2D domain using a Quadtree grid. This conversion involves refining the 2D cells within the channel to smaller sizes, ensuring the model accurately represents the flow behaviour. Once this modification is complete, the AD functionality can provide detailed insights into particle travel times and help demonstrate the effects of reprofiling or attenuation measures on downstream areas.

== Can TUFLOW generate 2D Plot (Time-Series) Output for Advection Dispersion results? ==
Currently, TUFLOW does not support 2D Plot (Time-Series) Output for Advection Dispersion results at specific point locations.

However, results can be extracted using output zones. Defining smaller output zones allows high-frequency data to be generated for areas of interest while managing file sizes efficiently. Multiple output zones can also be used to monitor widely separated locations.

== How can initial tracer concentrations and SGS parameters be managed in the Advection Dispersion functionality? ==
Initial tracer concentrations can be applied to dry cells, and these concentrations are mobilised as the cells become wet during a simulation. The initial water level in dry cells is set as the bed elevation plus the Cell Wet/Dry Depth. This depth determines the initial tracer volume available for advection once the cell becomes inundated.

When SGS (Sub-Grid Sampling) is used, the initial water volume is derived from a pre-calculated “level vs cell volume” curve. Tracer concentrations are distributed across this calculated volume. This ensures accurate representation of tracer movement, even in partially wet cells.

== How can the Advection Dispersion functionality be used to determine water residency time? ==
The Advection Dispersion functionality in TUFLOW can be used to calculate water residency time by modelling it as a scalar variable. This approach provides a method for tracking the duration water has spent within a specific area, such as a wetland, and is visualised in the model output as a time-based scalar field. This approach has some limitations:
* Output Capabilities: While TUFLOW supports various output formats (e.g., XMDF, DAT, NC), extracting detailed time-series data for specific constituents at individual locations may require additional post-processing. The current AD functionality does not explicitly support direct Point Output (PO) functionality for constituent data.
* Post-Processing Requirements: To obtain detailed residency time information at specific points, output zones may be required along with refined post-processing techniques. Defining output zones allows high-frequency scalar data to be captured in areas of interest, which can then be analysed to estimate residency times.
* Engine-Specific Features: Unlike the TUFLOW FV engine, which includes a particle tracking module for explicit tracking of water age, the fixed grid engine’s AD module relies on scalar-based methods to approximate residency time. For calculating water residency time with the AD functionality, properly configuring scalar outputs and planning post-processing steps are essential for accurate results.

== How can the Advection Dispersion functionality simplify firewater containment modelling? ==
The Advection Dispersion functionality in TUFLOW can simplify firewater containment modelling by using passive tracers to track firewater flow and concentration. Instead of running separate simulations for rainfall and firewater scenarios, the AD functionality enables a single simulation where tracers represent the firewater. This approach reduces modelling complexity while maintaining accuracy.

For example, a model with direct rainfall over the entire domain applies a passive tracer via 2d source area (2d_sa) polygons. The output can be set up to identify areas with tracer concentrations above a certain threshold, distinguishing firewater extents from other inundated areas. Areas outside of this represent zones with zero tracer concentration. Tracers can also include decay and settling parameters for added flexibility. This method not only simplifies the process but also ensures compliance with the UK CIRIA (Construction Industry Research and Information Association) guidance by integrating rainfall and firewater scenarios into a single simulation.

== What guidance is available for Non-Newtonian mixing exponents and dispersion coefficients in the Advection Dispersion functionality? ==
The Non-Newtonian Mixing Exponents (m, o, and p) were introduced in the 2023-03-AC release to improve how TUFLOW models non-Newtonian fluids. These exponents control how yield stress and density change as fluid concentration varies.

Previously, using a single exponent for all properties was ineffective for fluids with high solids content. For example, yield stress can increase rapidly with small changes in solids, while density changes more gradually.

It is recommended that these exponents range between 1 and 5. However, the optimal values depend on the specific fluid being modelled, and should be selected based on the fluid’s properties. TUFLOW does not provide specific default values.

For dispersion coefficients:

* In pure water, the longitudinal dispersion coefficient (KL) is usually between 6 and 13, and the transverse dispersion coefficient (KT) is between 0.15 and 1.6.

* Extremely high values, like 7500, only occur in special conditions such as estuarine environments with a halocline and are not typical for most cases.

Currently, there is no guidance for dispersion coefficients when mixing pure water with non-Newtonian fluids. Suitable values should be determined based on laboratory tests or studies specific to the fluid being modelled.

== What are the limitations of the Advection Dispersion functionality when modelling Non-Newtonian flow through 1D elements? ==
When using the Advection Dispersion functionality for non-Newtonian flow in models that include 1D elements, the following simplifications and limitations apply:

Flow Calculation:
* The flow through 1D elements (e.g., culverts) is calculated based on the assumption of pure water.
* Non-Newtonian properties, such as viscosity or yield stress, are not considered in the 1D engine. This simplification can lead to an overestimation of flow rates when dealing with non-Newtonian fluids.
Tracer Transport:
* By default, the concentration of the non-Newtonian fluid is passed instantly from the upstream to the downstream node in 1D channels.
* The transport equation is not calculated for the 1D elements. This can cause an underestimation of travel time for non-Newtonian fluids, particularly in long 1D elements.

These limitations mean that while the AD module can be used in models with 1D elements, it does not fully capture the complexities of non-Newtonian fluid behaviour in those elements. If higher accuracy is required, 2D elements where non-Newtonian properties are more comprehensively represented may be considered.

== Can the Advection Dispersion functionality be used in a model to simulate salinity? ==
Yes, the Advection Dispersion functionality can be used with models to simulate salinity transport, as long as the system is relatively well mixed vertically.

TUFLOW HPC is a 2D shallow water equation solver, so it does not account for vertical salinity gradients. This means it is best suited for rivers, shallow lakes, and estuaries where haloclines are weak or absent. Different boundary inflows can be assigned varying time series of salinity concentrations, and the module will simulate how these mix over space and time.

If the system has strong density stratification or distinctly three dimensional flow behaviour, a fully 3D solver such as TUFLOW FV is recommended.

== Can the Advection Dispersion functionality simulate pollutant runoff and transport from catchments? ==
Yes, the Advection Dispersion functionality can also be used to simulate pollutant runoff from catchments. This includes modelling the generation, transport, and fate of pollutants such as suspended sediment, nitrogen, and phosphorus.

Pollutants can be generated based on modelled bed shear stress, then transported through the domain using the flow field. The model can also apply decay and settling rates as part of the simulation.

The TUFLOW CATCH module, with which the Advection-Dispersion functionality is included, provides the capability to simulate pollutant runoff and transport from catchments. See the [https://www.tuflow.com/products/tuflow-catch-module/ TUFLOW Website] for further information.

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Education Licence New User Guide

2026-02-24T13:36:16Z

Tuflowduncan: /* TUFLOW Research Licence */

There are a number of options available for University education and research purposes:
* Teach TUFLOW using the licence free TUFLOW tutorials.
* Teach TUFLOW or conduct research using your own dataset via TUFLOW's free education (demo) mode.
* Purchase a research licence.

The following information is not applicable to commercial use of TUFLOW. 

=TUFLOW Tutorial Models=
Educators are welcome to use the licence free TUFLOW tutorial models and documentation as an education dataset. The benefit of this approach is that there will be no licencing complications for the students. Students will be able to run simulations on any computer at any time. Visit [[Tutorial_Introduction | TUFLOW Wiki Self-teach Tutorials]]. 

Educators are welcome to create course content from this dataset. Alternatively, the TUFLOW Team have previously created 10 weeks worth of university teaching material, including 2 weeks worth of assessment, using the tutorial dataset for the guided modelling tasks. If you would like assistance creating similar teaching material please email [mailto:training@tuflow.com training@tuflow.com].

=TUFLOW's Free Education (Demo) Mode=

Universities are welcome to use TUFLOW's licence free Demo mode for research or education purposes. The free Demo option is included within the standard TUFLOW executable. It is fully enabled, will function in any geographic region, though has the following limits:
:*100,000 total cells and 30,000 active (potentially flooded) cells
:*100 1D channels
:*There can only be one CPU 2D domain (M2D is not supported). HPC Quadtree is supported.
:*A simulation time of 10 minutes.
:*CPU and GPU compute are supported.
The free Demo mode is called using the TUFLOW Control File (TCF) command: <tt>Demo Model </tt> <tt>== </tt><tt>ON</tt> 

Educators who would like to teach TUFLOW can create course content that works within the limits of the Demo mode. If you would like assistance creating teaching material using this simulation mode please email [mailto:training@tuflow.com training@tuflow.com].

=TUFLOW Research Licence=
Unrestricted academic licences can be purchased by Universities for non-commercial research and educational use. Please email [mailto:sales@tuflow.com sales@tuflow.com] for more information..

Hardware Benchmarking - Results

2026-02-13T12:04:03Z

Tuflowduncan: /* CPU Results */

=CPU Results=
The following table summarises the runtimes for a range of computers. More will be added when additional results are obtained. The table is ordered based on the combined 20m Classic and HPC CPU runtimes, with the fastest computers at the top of the table.
 
'''Runtimes for CPU benchmarks'''
{| align="center" class="wikitable" style="position:relative;"

! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" | Processor Name
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=10% | Processor Frequency (GHz)**
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=10% | RAM size (GB)
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=10% | RAM frequency (MHz)
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=10% | Classic 20m (mins)
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=10% | HPC CPU 20m (mins)
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=10% | Runtime Combined (mins)
! style="background-color:#C5C5C5; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=12% | System Name
|-
|13th Gen Intel(R) Core(TM) i9-13900KS (32 CPUs) @ 3.2GHz||3.2||128||5200||32.7||108.6||141.3||JB1
|-
|13th Gen Intel(R) Core(TM) i9-13900KS (32 CPUs) @ 3.2GHz||3.2||64||5600||36.7||114.2||150.9||TM1
|-
|13th Gen Intel(R) Core(TM) i9-13900K (32 CPUs), ~3.0GHz
|3
|32
|4800
|41.9
|122.4
|164.3
|RA1
|-
|13th Gen Intel(R) Core(TM) i9-13900F (32 CPUs) @ 2.0GHz ||2.0||128||4000||41.2||124.1||165.3||AW1
|-
|12th Gen Intel(R) Core(TM) i9-12900K (24 CPUs)||3.2||128||4800||38.5||127.0||165.5||SB1
|-
|AMD Ryzen 9 7950X 16-Core Processor (32 CPUs) @ 4.5GHz||4.5||64||4800||33.4||136.0||169.4||PSM
|-
|12th Gen Intel(R) Core(TM) i9-12900K||3.2||128||3200||40.7||129.9||170.6||DD2
|-
|12th Gen Intel(R) Core(TM) i7-12700 (20 CPUs) @ ~2.1GHz||2.1||64||4800||41||137.2||178.2||RB1
|-
|AMD Ryzen 7 7800X3D 8-Core Processor (16 CPUs) @ ~4.2GHz||4.2||32||4800||35.5||162.8||198.3||LC1
|-
|11th Gen Intel(R) Core(TM) i7-11700 @ 2.50GHz (16 CPUs)||2.5||16||3200||48.4||170.5||218.9||TS1
|-
|Intel(R) Xeon(R) w5-2455X (24 CPUs) @ ~3.2GHz||3.2||64||4800||53.3||169.1||222.4||CHR
|-
|Intel(R) Core(TM) i9-10900K CPU @ 3.70GHz||3.7||128||3200||56.9||173.8||230.7||CH1
|-
|Intel(R) Core(TM) i9-9900K CPU @ (5.10GHz)||(5.1)||16||4000||58.2||179.9||238.1||RRB
|-
|AMD Ryzen 5 7600X 6-Core Processor||4.7||32||4800||39.0||175.7||214.7||HP1
|-
|Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz||3.7||64||3000||55.7||186.2||241.9||RH1
|-
|AMD Ryzen 9 3900X 12-Core Processor||3.8||64||3200||45.9||203.1||249.0||CH3
|-
|Intel(R) Core(TM) i9-9900 CPU @ 3.10GHz||3.1||32||2666||61.7||190.0||251.7||CB1
|-
|Intel(R) Core(TM) i9-9900KF CPU @ 3.60GHz||3.6||32||2133||61.4||190.4||251.8||RH2
|-
|Intel(R) Core(TM) i7-9700K CPU @ 3.60GHz (8 CPUs), ~3.6GHz||3.6||64||2133||62.7||191.1||253.8||PA1
|-
|Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz||3.7||32||2933||62.1||192.8||254.9||DS2
|-
|Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz||3.6||32||2666||71.2||184.3||255.5||ABA
|-
|Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz||3.6||32||2666||62.1||193.7||255.8||MA2
|-
|AMD EPYC 74F3 24-Core Processor (36 CPUs), ~3.2GHz
|3.2
|450
|
|50.0
|211.6
|261.6
|YW1
|-
|AMD Ryzen Threadripper 3970X 32-Core Processor||3.7||256||2400||49.5||212.1||261.6||CH2
|-
|AMD Ryzen 9 3950X 16-Core Processor||3.5||128||2800||55.9||210.0||265.9||TRO
|-
|AMD EPYC 74F3 24-Core Processor (6 CPUs) @ 3.2GHz||3.2||56||N/A||49.1||218.9||268||RBR
|-
|Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz||3.7||64||2133||67.0||202.5||269.5||RL1
|-
|Intel(R) Core(TM) i9-9900X CPU @ 3.50GHz||3.5||128||2133||72.7||202.1||274.8||MBL
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz||4.2||64||2133||67.5||208.6||276.1||SKI
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz||4.2||64||2133||68.5||208.8||277.3||PM2
|-
|Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz||3.6||32||2666||66.8||211.6||278.1||MA1
|-
|Intel(R) Core(TM) i7-8700 CPU @ 3.20GHz||3.2||16||2667||68.2||211.8||280.0||CR2
|-
|Intel(R) Xeon(R) E-2176M CPU @ 2.70GHz||2.7||32||2667||68.0||216.0||284.0||RL3
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz||4.2||32||2113||68.2||217.9||286.1||HP2
|-
|Intel(R) Xeon(R) E-2176M CPU @ 2.70GHz||2.7||32||2667||67.7||219.1||286.8||RL2
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz||4.2||64||2133||70.5||218.8||289.3||PM1
|-
|Intel(R) Core(TM) i9-8950HK CPU @ 2.90GHz||2.9||16||2667||77.5||212.6||290.1||KTC
|-
|Intel(R) Xeon(R) W-2255 CPU @ 3.70GHz||3.7||32||2933||75.2||219.8||295||BL-DT01001
|-
|AMD Ryzen Threadripper 2950X 16-Core Processor||3.5||128||2666||67.9||230.8||298.7||JGR
|-
|AMD Ryzen Threadripper 2950X 16-Core Processor (32 CPUs) @ 3.5GHz||3.5||128||2666||66.3||234.7||301||JG3
|-
|Intel(R) Core(TM) i9-7900X CPU @ 3.30GHz||3.3||32||2400||80.5||221.9||302.4||JM1
|-
|Intel(R) Core(TM) i7-7700 CPU @ 3.60GHz||3.6||16||2400||72.8||230.6||303.4||RSH
|-
|Intel(R) Core(TM) i7-7820X CPU @ 3.60GHz||3.6||64||2666||85.4||218.8||304.2||JPI
|-
|Intel(R) Core(TM) i7-7820X CPU @ 3.60GHz||3.6||64||2666||83.7||225.2||308.9||HNM
|-
|11th Gen Intel(R) Core(TM) i9-11950H @ 2.60GHz (16 CPUs), ~2.6GHz
|2.6
|32
|3200
|66.6
|243.3
|309.9
|SK1
|-
|Intel(R) Core(TM) i7-4790K CPU @ 4.00GHz||4.0||32||2400||91.2||223.3||314.5||BRD
|-
|Intel(R) Xeon(R) CPU E5-1630 v4 @ 3.70GHz||3.7||64||2400||84.5||236.6||321.2||DS1
|-
|Intel(R) Core(TM) i7-6900K CPU @ 3.20GHz||3.2||128||2133||83.4||243.1||326.5||BLK
|-
|Intel(R) Core(TM) Ultra 7 155H (22 CPUs) @ 1.4GHz||1.4||16||7467||173.8||152.8||326.6||AL1
|-
|Intel(R) Xeon(R) W-2255 CPU @ 3.70GHz (20 CPUs)||3.7||64||2933||95.4||231.3||326.7||JB2
|-
|Intel(R) Core(TM) i7-6800K CPU @ 3.40GHz||3.4||128||2400||85.3||247.7||332.9||615
|-
|Intel(R) Core(TM) i7-5960X CPU @ 3.00GHz||3.0||64||2400||106.3||226.7||333.0||MRT
|-
|Intel(R) Core(TM) i7-6700 CPU @ 3.40GHz||3.4||16||2133||80.7||253.4||334.1||VHD
|-
|Intel(R) Xeon(R) Gold 6130 CPU @ 2.10GHz||2.1||64||2666||83.9||251.2||335.1||AR2
|-
|AMD EPYC 7V12 64-Core Processor (16 CPUs) ||2.4||57||NA||63.5||277.6||341.1||CS2
|-
|Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz (12 CPUs), ~3.7GHz
|3.7
|32
|2666
|91.45
|259.63
|351.1
|SS1
|-
|AMD Ryzen Threadripper 1950X 16-Core Processor||3.4||16||2666||81.9||277.3||359.2||CEV
|-
|Intel(R) Xeon(R) CPU E3-1505M v6 @ 3.00GHz||3.0||32||2400||84.9||278.4||363.3||GHY
|-
|Intel(R) Core(TM) i7-6700 CPU @ 3.40GHz||3.4||64||2133||82.3||289.8||372.1||JIW
|-
|Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz||3.4||32||1666||108.9||270.0||378.9||AR1
|-
|Intel(R) Xeon(R) W-2235 CPU @ 3.80GHz (12 CPUs)||3.8||64||3200||87.8||294.2||382||HDR-A2000
|-
|AMD Ryzen 9 5950X 16-Core Processor||3.4||32||3400||39.7||343.0||382.7||JG2
|-
|Intel(R) Core(TM) i7-4810MQ CPU @ 2.80GHz||2.8||32||1600||119.7||280.8||400.5||SBC
|-
|Intel(R) Core(TM) i7-5820K CPU @ 3.30GHz||3.3||64||2133||118.2||287.8||406.0||ZDO
|-
|Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz||2.7||16||2133||90.4||321.7||412.1||EAS
|-
|Intel(R) Core(TM) i9-7900X CPU @ 3.30GHz||3.3||16||2133||84.8||336.9||421.7||JM2
|-
|Intel(R) Core(TM) i7-5960X CPU @ 3.00GHz||3.0||64||2133||100.3||323||423.3||MON
|-
|Intel(R) Xeon(R) CPU E3-1240 V2 @ 3.40GHz||3.4||32||1600||126.4||299.7||426.1||MAV
|-
|Intel(R) Core(TM) i7-1185G7 @ 3.00GHz ||3.0||4||986||84.0||351.4||435.4||TJS
|-
|Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz ||3.5||16||1333||125.9||320.5||446.4||EFC
|-
|Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz||1.9||16||1800||100.1||347.0||447.1||SM1
|-
|Intel(R) Core(TM) i7-10700F CPU @ 2.90GHz ||2.9||16||2900||63.3||385.0||448.3||NCV
|-
|Intel(R) Core(TM) i5-10600K CPU @ 4.10GHz ||4.1||16||4104||62.7||386.6||449.3||GZH
|-
|Intel(R) Xeon(R) Silver 4214R CPU @ 2.40GHz ||2.4||128||2394||130.5||331.5||462||VDI
|-
|Intel(R) Core(TM) i7-5600U CPU @ 2.60GHz||2.6||24||1600||100.5||378.6||479.1||CDH
|-
|Intel(R) Xeon(R) CPU E5-1650 0 @ 3.20GHz||3.2||32||1600||143.2||343.1||486.3||MPR
|-
|Intel(R) Core(TM) i5-3470 CPU @ 3.20GHz||3.2||8||1600||142.0||349.4||491.4||CR1
|-
|Intel(R) Xeon(R) CPU E5-2667 v2 @ 3.30GHz||3.3||16||N/A||196.8||331.5||528.3||Private Cloud
|-
|Intel(R) Core(TM) i7-4712HQ CPU @ 2.30GHz (Laptop)||2.3||8||1600||145.2||414.4||559.6||MNG
|-
|Intel(R) Xeon(R) CPU X5680 @ 3.33GHz||3.33||72||1333||165.7||400.6||566.3||WTM
|-
|Intel(R) Core(TM) i7-4700MQ CPU @ 2.40GHz (Laptop)||2.4||8||1600||137.8||795.0||932.8||HMM
|-
|}

=GPU Results=
The following table summarises the runtimes for a range of computers. More will be added when additional results are obtained. The table is ordered based on the combined 20m and 10m runtimes with the fastest computers at the top of the table.
 
The HPC GPU benchmark only uses a single GPU card. TUFLOW HPC GPU can be run across multiple NVIDIA GPU devices. However, the benefits of these are typically more noticeable for larger models with more than 1 million cells.
 
'''Runtimes for GPU benchmarks'''
{| align="center" class="wikitable" style="position:relative;"
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" | Processor Name
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=24% | Graphics Card**
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=8% | GPU RAM (GB)
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=8% | Number of CUDA Cores*
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=8% | Runtime 20m (mins)
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=8% | Runtime 10m (mins)
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=8% | Combined Runtime (mins)
! style="background-color:#C5C5C5; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=12% | System Name
|-
|AMD Ryzen 9 9950X3D 16-Core Processor (32 CPUs), ~4.3GHz
|NVIDIA GeForce RTX 5090
|32
|21760
|2.5
|9.5
|12.0
|JW3
|-
|13th Gen Intel(R) Core(TM) i7-13700KF (24 CPUs), @ 3.4GHz ||NVIDIA GeForce RTX 4090||24||16384||2.4||11.6||14.0||JW1
|-
|13th Gen Intel(R) Core(TM) i9-13900KS (32 CPUs) @ 3.2GHz ||NVIDIA GeForce RTX 4090||24||16384||2.5||12.1||14.6||JB1
|-
|13th Gen Intel(R) Core(TM) i9-13900K (32 CPUs) @ 3.0GHz ||NVIDIA GeForce RTX 4090||24||16384||2.7||12.7||15.4||TA1
|-
|AMD Ryzen 9 7950X 16-Core Processor (32 CPUs) @ 4.5GHz ||NVIDIA GeForce RTX 4090||24||16384||2.9||12.7||15.6||PSM
|-
|AMD Ryzen 9 3900X 12-Core Processor (24 CPUs) @ 3.8GHz ||NVIDIA GeForce RTX 4090||24||16384||3.1||13.3||16.4||CR4
|-
|Intel(R) Core(TM) i9-14900K (32 CPUs) @ ~3.2GHz||NVIDIA GeForce RTX 4080 Super||16||10240||2.8||14.5||17.3||DF2
|-
|13th Gen Intel(R) Core(TM) i9-13900KS (32 CPUs) @ 3.2GHz ||NVIDIA GeForce RTX 4080||16||9728||2.8||14.7||17.5||TM1
|-
|12th Gen Intel(R) Core(TM) i9-12900 (24 CPUs) @ 2.4GHz ||NVIDIA GeForce RTX 4080||16||9728||2.8||14.7||17.5||JM3
|-
|13th Gen Intel(R) Core(TM) i9-13900F (32 CPUs) @ 2.0GHz ||NVIDIA GeForce RTX 4080||16||9728||3.2||15.0||18.2||AW1
|-
|AMD Ryzen 9 9900X 12-Core Processor (24 CPUs), ~4.4GHz
|NVIDIA GeForce RTX 5070 Ti
|16
|8960
|3.2
|15.0
|18.2
|TM2
|-
|AMD Ryzen 7 7800X3D 8-Core Processor (16 CPUs)@ ~4.2GHz||NVIDIA GeForce RTX 4080 SUPER||16||10240||3.2||15.7||18.9||LC1
|-
|AMD Ryzen Threadripper 2950X 16-Core Processor (32 CPUs) @ 3.5GHz||NVIDIA RTX 6000 Ada Generation||48||18176||4.9||14.2||19.1||JG3
|-
|Intel(R) Xeon(R) CPU E5-2697 v4 @ 2.30GHz (72 CPUs)||NVIDIA GeForce RTX 4090||24||16384||3.9||16.2||20.1||CS3
|-
|Intel(R) Xeon(R) CPU @ 2.30GHz ||NVIDIA Tesla V100||16||5120||3.4||18.5||21.9||FM-NODE: Tesla V100
|-
|AMD Ryzen 5 7600X 6-Core Processor ||NVIDIA GeForce RTX 4070 Ti||12||7680||3.4||19.2||22.6||HP1
|-
|AMD Ryzen 7 5800X 8-Core Processor (~3.8 GHz)
|NVIDIA GeForce RTX 5070
|12
|6144
|3.9
|19.07
|22.97
|PW1
|-
|AMD Ryzen 9 5900X 12-Core Processor ||NVIDIA GeForce RTX 3080 Ti||12||10240||3.8||19.2||23.0||RS1
|-
|12th Gen Intel(R) Core(TM) i9-12900K ||NVIDIA GeForce RTX 3090||24||10496||3.7||19.4||23.1||DD2
|-
|12th Gen Intel(R) Core(TM) i7-12700F
|NVIDIA GeForce RTX 3080 Ti
|12
|10240
|3.75
|19.57
|23.32
|AUBNE1PC6602
|-
|AMD Ryzen 9 5900X 12-Core Processor ||NVIDIA GeForce RTX 3080 Ti||12||10240||4.0||19.6||23.6||GP1
|-
|Intel(R) Xeon(R) Gold 5317 CPU @ 3.00GHz (48 CPUs) ||NVIDIA A40||48||10752||3.5||20.3||23.8||Lenovo SR650 V2
|-
|AMD Ryzen 9 5900X 12-Core Processor ||NVIDIA GeForce RTX 3090||24||10496||4.1||20.1||24.2||JMM
|-
|AMD Ryzen 9 3900X 12-Core Processor ||NVIDIA GeForce RTX 3090||24||10496||4.4||20.4||24.8||CH3
|-
|Intel(R) Core(TM) i9-10980XE CPU @ 3.00GHz (36 CPUs), ~3.0GHz
|NVIDIA RTX A6000
|48
|10752
|4.7
|22.7
|27.4
|CB2
|-
|13th Gen Intel(R) Core(TM) i5-13600HX (20 CPUs) @ ~2.6GHz ||NVIDIA GeForce RTX 4090 Laptop GPU||16||9728||5.3||22.2||27.5||LC2
|-
|12th Gen Intel(R) Core(TM) i7-12700 (20 CPUs) @ ~2.1GHz ||NVIDIA GeForce RTX 3080||10||8704||4.3||23.7||28||RB1
|-
|AMD Ryzen 9 3900X 12-Core Processor ||NVIDIA GeForce RTX 3080||10||8704||4.6||23.5||28.1||KW2
|-
|12th Gen Intel(R) Core(TM) i9-12900K (24 CPUs) ||NVIDIA RTX A5000||24||8192||4.4||24.1||28.5||SB1
|-
|Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz ||NVIDIA GeForce RTX 3080||10||8704||4.7||24.0||28.7||CPM
|-
|Intel(R) Xeon(R) W-2223 CPU @ 3.60GHz ||NVIDIA GeForce RTX 3090||24||10496||5.3||24.3||29.6||SSM2
|-
|Intel(R) Core(TM) i9-9900KF CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||4.7||25.7||30.4||ACH
|-
|AMD Ryzen Threadripper 2950X 16-Core Processor ||NVIDIA TITAN RTX||24||4608||5.7||25.2||30.9||JGR
|-
|AMD Ryzen Threadripper 2920X 12-Core Processor (24 CPUs) @ 3.5GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||5.1||25.9||31||CR5
|-
|Intel(R) Xeon(R) W-2145 CPU @ 3.70GHz (16 CPUs), ~3.7GHz
|NVIDIA RTX A5000
|24
|8192
|5.2
|26.3
|31.5
|CB3
|-
|AMD Ryzen 9 3950X 16-Core Processor ||NVIDIA GeForce RTX 2080 Ti||11||4352||5.3||26.4||31.7||TRO
|-
|Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||5.4||27.4||32.8||PY2
|-
|Intel(R) Core(TM) i7-6700k @ 4.00GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||5.7||27.7||33.4||VLD
|-
|Intel(R) Core(TM) i7-10700F CPU @ 2.90GHz ||NVIDIA GeForce RTX 3070||8||5888||5.0||28.8||33.8||NCV
|-
|Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||5.5||28.4||33.9||RL1
|-
|Intel(R) Core(TM) i9-9900K CPU @ (5.10GHz) ||NVIDIA GeForce RTX 2080 (core 2100MHz, mem 8000MHz)||8||2944||5.5||28.7||34.2||RRB
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||5.9||28.4||34.3||HP2
|-
|Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||5.8||28.8||34.6||MA1
|-
|Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||5.7||29.2||34.9||MA2
|-
|AMD Ryzen 9 5950X 16-Core Processor ||NVIDIA GeForce RTX 3070||8||5888||5.5||29.7||35.2||JG2
|-
|Intel(R) Core(TM) i9-9900X CPU @ 3.50GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||5.6||29.9||35.5||MBL
|-
|Intel(R) Core(TM) i7-7820X CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||6.4||29.5||35.9||JPI
|-
|Intel(R) Xeon(R) CPU @ 2.30GHz ||NVIDIA Tesla P100||16||3584||6.1||30.8||36.9||Google Cloud: Tesla P100
|-
|Intel(R) Core(TM) i9-9900KF CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080 SUPER||8||3072||5.7||31.9||37.6||RH2
|-
|Intel(R) Xeon(R) Gold 6230R CPU @ 2.10GHz ||NVIDIA GRID RTX8000P-48Q||48||4608||6.8||31.0||37.8||VJ1
|-
|Intel(R) Core(TM) i7-10700K CPU @ 3.80GHz (16 CPUs) ||NVIDIA RTX A4000||16||6144||5.8||32.0||37.8||JS2
|-
|Intel(R) Core(TM) i7-6700k @ 4.00GHz ||NVIDIA GeForce RTX 2080||8||2944||6.0||31.9||37.9||ANK
|-
|Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz ||NVIDIA GeForce RTX 2080 SUPER||8||3072||6.0||32.0||38.0||EFC
|-
|AMD EPYC 74F3 24-Core Processor (36 CPUs), ~3.2GHz
|NVIDIA A10-24Q
|22
|9216
|7.2
|31.4
|38.6
|YW1
|-
|AMD EPYC 74F3 24-Core Processor (36 CPUs) @ 3.2GHz ||NVIDIA A10-24Q||24||8192||7.2||31.4||38.6||CS1
|-
|Intel(R) Core(TM) i7-9700K CPU @ 3.60GHz (8 CPUs), ~3.6GHz||NVIDIA GeForce RTX 2080 Ti||11||4352||5.4||33.3||38.7||PA1
|-
|11th Gen Intel(R) Core(TM) i7-11700 @ 2.50GHz (16 CPUs) ||NVIDIA GeForce RTX 3060 Ti (LHR) ||8||4864||5.7||33.3||39.0||DF1
|-
|Intel(R) Core(TM) i5-10600K CPU @ 4.10GHz ||NVIDIA GeForce RTX 2060 SUPER (core 1647MHz, mem 1750MHz)||8||2176||5.6||33.4||39.1||GZH
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz ||NVIDIA GeForce RTX 2080||8||2944||5.6||34.3||40.7||PM2
|-
|AMD Ryzen Threadripper 2990WX 32-Core Processor ||NVIDIA TITAN Xp||12||3840||6.9||34.6||41.6||FLC
|-
|Intel(R) Xeon(R) W-2255 CPU @ 3.70GHz (20 CPUs)||NVIDIA GeForce GTX 1080 Ti||11||3584||6.5||35.1||41.6||JB2
|-
|Intel(R) Xeon(R) CPU E5-1620 v3 @ 3.50GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||6.4||35.8||42.2||JS1
|-
|Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080||8||2944||6.5||36.0||42.5||ABA
|-
|Intel(R) Xeon(R) w5-2455X (24 CPUs) @ ~3.2GHz ||NVIDIA RTX A4000||16||6144||7.2||35.3||42.5||CHR
|-
|Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||6.1||37.1||43.2||RH1
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||6.5||37.4||43.8||PM1
|-
|Intel(R) Core(TM) i7-5960X CPU @ 3.00GHz ||NVIDIA GeForce GTX 2070||8||2304||7.4||38.8||46.2||MMR
|-
|Intel(R) Core(TM) i9-9900 CPU @ 3.10GHz ||NVIDIA Quadro RTX 4000||8||2304||6.6||39.8||46.4||CB1
|-
|Intel(R) Core(TM) i7-6800K CPU @ 3.40GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||7.8||39.1||46.9||615
|-
|Intel(R) Core(TM) i7-6850K CPU @ 3.60GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||8.0||39.3||47.3||RCD
|-
|AMD Ryzen 7 7840HS ||NVIDIA GeForce RTX 4060 Laptop GPU||8||3072||7.0||40.6||47.6||CH1
|-
|Intel(R) Core(TM) i7-7820X CPU @ 3.60GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||7.6||41.1||48.7||HNM
|-
|Intel(R) Xeon(R) Silver 4214R CPU @ 2.40GHz ||NVIDIA GRID RTX6000P-4Q||24||4608||10.5||39.3||49.8||VDI
|-
|Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz (Laptop) ||NVIDIA GeForce RTX 2070||8||2304||7.7||42.8||50.5||ERX
|-
|Intel(R) Xeon(R) Gold 5317 CPU @ 3.00GHz (48 CPUs) ||NVIDIA Tesla T4||16||2560||6.8||45.2||52.0||RJ1
|-
|11th Gen Intel(R) Core(TM) i7-11700 @ 2.50GHz
|NVIDIA GeForce RTX 3060
|8
|3584
|7.68
|45.92
|53.6
|AUBNEW1DQ54G3
|-
|Intel(R) Core(TM) i7-6900K CPU @ 3.20GHz ||NVIDIA GeForce GTX 1080||8||2560||8.0||47.4||55.3||BLK
|-
|Intel(R) Xeon(R) CPU @ 2.30GHz ||NVIDIA Tesla T4||16||2560||7.3||48.3||55.6||FM-NODE: Tesla T4
|-
|Intel(R) Core(TM) i9-7900X CPU @ 3.30GHz ||NVIDIA GeForce GTX 1080||8||2560||8.5||48.9||57.3||JM1
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz ||NVIDIA GeForce GTX 1070||8||1920||8.2||51.9||60.0||SKI
|-
|Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz (12 CPUs), ~3.7GHz
|NVIDIA GeForce GTX 1080
|8
|2560
|9.13
|52.13
|61.3
|SS1
|-
|Intel(R) Xeon(R) Gold 6130 CPU @ 2.10GHz ||NVIDIA Quadro P5000||16||2560||9.6||51.8||61.4||AR2
|-
|Intel(R) Xeon(R) W-2235 CPU @ 3.80GHz (12 CPUs)||NVIDIA RTX A2000||6||3328||9.1||54.4||63.5||HDR-A2000
|-
|Intel(R) Core(TM) i7-6700K CPU @ 4.00GHz ||NVIDIA GeForce GTX 1070||8||1920||8.9||54.9||63.8||PY1
|-
|Intel(R) Core(TM) Ultra 7 155H (22 CPUs) @ 1.4GHz ||NVIDIA GeForce RTX 4050 Laptop GPU||6||2560||7.9||59.4||67.3||AL1
|-
|13th Gen Intel(R) Core(TM) i9-13900K (32 CPUs), ~3.0GHz
|NVIDIA GeForce RTX A2000
|12
|3328
|8.6
|59.5
|68.1
|RA1
|-
|Intel(R) Xeon(R) CPU E5-1630 v4 @ 3.70GHz ||NVIDIA GeForce GTX 1070||8||1920||10.3||59.3||69.5||DS1
|-
|Intel(R) Core(TM) i7-8700 CPU @ 3.20GHz ||NVIDIA GeForce GTX 1660||6||1408||9.4||61.0||70.4||JFP
|-
|Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz ||NVIDIA Quadro P4000||8||1792||10.0||62.3||72.3||DS2
|-
|11th Gen Intel(R) Core(TM) i7-11700 @ 2.50GHz (16 CPUs) ||NVIDIA GeForce GTX 1650 SUPER||4||1280||10.3||64.6||74.9||TS1
|-
|Intel(R) Xeon(R) CPU @ 2.30GHz ||NVIDIA Tesla P4||8||2560||10.4||69.0||79.4||Google Cloud: Tesla P4
|-
|Intel(R) Core(TM) i7-5820K CPU @ 3.30GHz ||NVIDIA GeForce GTX 980||4||2048||11.8||70.6||82.3||ZDO
|-
|11th Gen Intel(R) Core(TM) i9-11950H @ 2.60GHz (16 CPUs), ~2.6GHz
|NVIDIA RTX A2000 Laptop GPU
|4
|2560
|11.4
|72.6
|84.0
|SK1
|-
|Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz ||NVIDIA GeForce GTX TITAN Black||6||2880||13.1||76.1||89.2||AR1
|-
|Intel(R) Core(TM) i7-7700 CPU @ 3.60GHz ||NVIDIA GeForce GTX 1060||6||1280||13.0||77.1||90.1||RSH
|-
|Intel(R) Xeon(R) CPU E5-2686 v4 @ 2.30GHz (64 CPUs), ~2.3GHz||NVIDIA Tesla M60||16||4096||12||82.7||94.7||SM2
|-
|Intel(R) Xeon(R) CPU @ 2.30GHz ||NVIDIA Tesla K80||12||2496||11.3||83.5||94.8||Google Cloud: Tesla K80
|-
|Intel(R) Core(TM) i3-8100 CPU @ 3.60GHz ||NVIDIA Tesla K40c||12||2880||12.3||83.1||95.3||NWE
|-
|Intel(R) Core(TM) i7-5960X CPU @ 3.00GHz ||NVIDIA Quadro T2000||4||1024||13.3||85.2||95.5||SSM
|-
|Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz (Laptop) ||NVIDIA GeForce GTX 980||4||2048||17.5||84.2||101.7||MRT
|-
|Intel(R) Core(TM) i7-10700K CPU @ 3.80GHz (16 CPUs), ~3.8GHz
|NVIDIA Quadro T1000
|4
|896
|13.6
|91.3
|104.9
|CB4
|-
|13th Gen Intel(R) Core(TM) i7-13800H (20 CPUs), ~2.5GHz
|NVIDIA RTX A500 Laptop GPU
|4
|2048
|14.8
|93.9
|108.7
|YB1
|-
|Intel(R) Xeon(R) W-2255 CPU @ 3.70GHz||NVIDIA Quadro P2000||5||1024||14.2||96||110.2||BL-DT01001
|-
|Intel(R) Core(TM) i7-8700 CPU @ 3.20GHz ||NVIDIA Quadro P2000||5||1024||15.8||100.1||115.9||CR2
|-
|Intel(R) Xeon(R) CPU E3-1240 V2 @ 3.40GHz ||NVIDIA GeForce GTX 690||2||3072||18.4||114.4||132.8||MAV
|-
|AMD Ryzen Threadripper 1950X 16-Core Processor ||NVIDIA GeForce GTX 960||4||1024||18.6||123.3||141.6||CEV
|-
|Intel(R) Core(TM) i7-6700 CPU @ 3.40GHz ||NVIDIA GeForce GTX 960||4||1024||19.9||127.2||147.1||VHD
|-
|Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz||NVIDIA GeForce GTX 1050 Ti||4||768||21.1||133.8||154.9||MJS
|-
|Intel(R) Core(TM) i9-7900X CPU @ 3.30GHz||NVIDIA GeForce GTX 1050||2||640||20.6||139.1||159.7||JM2
|-
|Intel(R) Core(TM) i9-8950HK CPU @ 2.90GHz||NVIDIA Quadro P2000||5||1024||22.1||142.5||164.6||KTC
|-
|Intel(R) Xeon(R) E-2176M CPU @ 2.70GHz||NVIDIA Quadro P2000||5||1024||23.0||149.3||172.3||RL2
|-
|Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz||NVIDIA Quadro M2200||4||1024||23.2||198.7||222.0||GYB
|-
|Intel(R) Core(TM) i7-1185G7 @ 3.00GHz||NVIDIA T500||4||986||29.3||197.5||226.8||TJS
|-
|Intel(R) Xeon(R) E-2176M CPU @ 2.70GHz ||NVIDIA Quadro P1000||4||640||30.3||203.7||234.0||RL3
|-
|Intel(R) Core(TM) i7-6700 CPU @ 3.40GHz ||NVIDIA Quadro K2200||4||640||32.5||211.3||243.8||JIW
|-
|AMD EPYC 74F3 24-Core Processor (6 CPUs) @ 3.2GHz||NVIDIA A10-4Q||24||8192||44.5||212.6||257.1||RBR
|-
|Intel(R) Xeon(R) CPU E3-1505M v6 @ 3.00GHz ||NVIDIA Quadro M1200||4||640||84.9||278.4||363.3||GHY
|-
|Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz ||NVIDIA GeForce GTX 940MX||2||384||65.6||479.0||544.6||EAS
|-
|Intel(R) Core(TM) i7-5600U CPU @ 2.60GHz||NVIDIA GeForce 840M||2||384||70.6||526.3||595.9||CDH
|-
|Intel(R) Core(TM) i7-4700MQ CPU @ 2.40GHz (Laptop)||NVIDIA GeForce GT 740M||2||384||102.3||694.0||796.3||HMM
|-
|}

=High End GPU Results=
A number of additional benchmarking tests have been completed on a 5m and 2.5m model on a single GPU card.

{| align="center" class="wikitable" style="position:relative;"
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" | Processor Name
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=24% | Graphics Card**
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=8% | GPU RAM (GB)
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=8% | Number of CUDA Cores*
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=8% | Runtime 5m (mins)
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=8% | Runtime 2.5m (mins)
! style="background-color:#005581; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=8% | Combined Runtime (mins)
! style="background-color:#C5C5C5; font-weight:bold; color:white; position:sticky; top:0; z-index:2;" width=12% | System Name
|-

|AMD Ryzen 9 9950X3D 16-Core Processor (32 CPUs), ~4.3GHz
|NVIDIA GeForce RTX 5090
|32
|21760
|73.3
|568.7
|642.0
|JW3
|-
|13th Gen Intel(R) Core(TM) i9-13900KS (32 CPUs) @ 3.2GHz||NVIDIA GeForce RTX 4090||24||16384||103.3||811.2||914.5||JB1
|-
|13th Gen Intel(R) Core(TM) i9-13900K (32 CPUs) @ 3.0GHz||NVIDIA GeForce RTX 4090||24||16384||105.9||813.7||919.6||TA1
|-
|13th Gen Intel(R) Core(TM) i7-13700KF (24 CPUs), @ 3.4GHz||NVIDIA GeForce RTX 4090||24||16384||103.7||824.3||928.0||JW1
|-
|AMD Ryzen 9 7950X 16-Core Processor (32 CPUs) @ 4.5GHz ||NVIDIA GeForce RTX 4090||24||16384||108.2||821.5||929.7||PSM
|-
|AMD Ryzen 9 3900X 12-Core Processor (24 CPUs) @ 3.8GHz ||NVIDIA GeForce RTX 4090||24||16384||106.8||875.5||982.3||CR4
|-
|AMD Ryzen Threadripper 2950X 16-Core Processor (32 CPUs) @ 3.5GHz ||NVIDIA RTX 6000 Ada Generation||48||18176||119.6||877.8||997.4||JG3
|-
|AMD Ryzen 9 9900X 12-Core Processor (24 CPUs), ~4.4GHz
|NVIDIA GeForce RTX 5070 Ti
|16
|8960
|134.0
|1049.9
|1183.9
|TM2
|-
|12th Gen Intel(R) Core(TM) i9-12900 (24 CPUs) @ 2.4GHz ||NVIDIA GeForce RTX 4080||16||9728||139.5||1115.1||1254.6||JM3
|-
|Intel(R) Xeon(R) CPU @ 2.30GHz ||NVIDIA Tesla V100||16||5120||155.2||1172.9||1328.1||FM-NODE: Tesla V100
|-
|AMD Ryzen 9 5900X 12-Core Processor ||NVIDIA GeForce RTX 3090||24||10496||155.5||1176.2||1331.7||JMM
|-
|AMD Ryzen 9 3900X 12-Core Processor ||NVIDIA GeForce RTX 3090||24||10496||158||1192.2||1350.2||CH3
|-
|Intel(R) Core(TM) i9-10900F CPU @ 3.70GHz ||NVIDIA GeForce RTX 3090||24||10496||162.3||1192.4||1354.7||LJA
|-
|AMD Ryzen 9 5900X 12-Core Processor ||NVIDIA GeForce RTX 3080 Ti||12||10240||159.7||1216.2||1375.9||GP1
|-
|12th Gen Intel(R) Core(TM) i9-12900K ||NVIDIA GeForce RTX 3090||24||10496||160.9||1240||1400.9||DD2
|-
|Intel(R) Xeon(R) Silver 4114 CPU @ 2.20GHz ||NVIDIA GeForce RTX 3090||24||10496||172.9||1249.8||1422.7||SIP
|-
|AMD Ryzen 7 5800X 8-Core Processor (~3.8 GHz)
|NVIDIA GeForce RTX 5070
|12
|6144
|172.5
|1343.4
|15.15.9
|PW1
|-
|AMD Ryzen 9 3900X 12-Core Processor ||NVIDIA GeForce RTX 3080||10||8704||178.9||1363.9||1542.8||KW2
|-
|AMD Ryzen 5 7600X 6-Core Processor ||NVIDIA GeForce RTX 4070 Ti||12||7680||190.2||1493.2||1683.4||HP1
|-
|Intel(R) Core(TM) i9-9900KF CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||203.8||1523.9||1727.7||ACH
|-
|AMD Ryzen Threadripper 2950X 16-Core Processor ||NVIDIA TITAN RTX||24||4608||201.2||1548.1||1749.3||JGR
|-
|Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||220.0||1634.5||1854.5||MA1
|-
|Intel(R) Core(TM) i7-7820X CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||222.2||1648.7||1870.9||JPI
|-
|Intel(R) Core(TM) i7-9700K CPU @ 3.60GHz (8 CPUs), ~3.6GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||215.9||1678.7||1894.6||PA2
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz ||NVIDIA GeForce RTX 2080 Ti||11||4352||255.4||1691.7||1947.1||HP2
|-
|AMD EPYC 74F3 24-Core Processor (36 CPUs), ~3.2GHz
|NVIDIA A10-24Q
|22
|9216
|242.3
|1856.5
|2098.8
|YW1
|-
|Intel(R) Core(TM) i9-9900K CPU @ (5.10GHz) ||NVIDIA GeForce RTX 2080 (core 2100MHz, mem 8000MHz)||8||2944||241.2||1863.5||2104.7||RRB
|-
|AMD Ryzen 9 5950X 16-Core Processor ||NVIDIA GeForce RTX 3070||8||5888||248.7||1928.6||2177.3||JG2
|-
|Intel(R) Core(TM) i9-9900KF CPU @ 3.60GHz ||NVIDIA GeForce RTX 2080 SUPER||8||3072||257.3||1957.7||2215.0||RH2
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz ||NVIDIA GeForce RTX 2080||8||2944||275.1||2147.4||2422.5||PM2
|-
|AMD Ryzen Threadripper 2990WX 32-Core Processor ||NVIDIA TITAN Xp||12||3840||296.0||2218.4||2514.4||FLC
|-
|Intel(R) Xeon(R) CPU E5-1620 v3 @ 3.50GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||298.9||2290.1||2589.0||JS1
|-
|Intel(R) Core(TM) i7-6800K CPU @ 3.40GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||311.3||2345.1||2656.4||615
|-
|Intel(R) Core(TM) i7-6850K CPU @ 3.60GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||310.3||2377.2||2687.5||RCD
|-
|Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||308.7||2384.7||2693.4||RH1
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||311.9||2404.9||2716.7||PM1
|-
|Intel(R) Core(TM) i7-7820X CPU @ 3.60GHz ||NVIDIA GeForce GTX 1080 Ti||11||3584||324.8||2475.3||2800.1||HNM
|-
|Intel(R) Core(TM) i7-6900K CPU @ 3.20GHz ||NVIDIA GeForce GTX 1080||8||2560||439.0||3379.3||3818.2||BLK
|-
|Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz ||NVIDIA GeForce GTX 1070||8||1920||475.5||3788.2||4263.7||SKI
|-
|}
<pre> * it is noted that the number of CUDA cores is not provided as an output from the '''dxdiag''' command and this information has been sourced from the nvidia website.
** The output cpu.txt only provides the 'out of the box' processor speed. If you have overclocked your cpu and/or gpu, please send these details to TUFLOW Support so we can add the overclocked data in brackets. </pre>

{{Tips Navigation
|uplink=[[Hardware_Benchmarking | Back to TUFLOW Benchmarking]]
}}

Green-Ampt Infiltration Parameters

2026-01-15T14:08:10Z

Tuflowduncan: Updates plots to make a bit more professional

== Introduction ==
TUFLOW provides several methods for modelling infiltration from the 2D surface into the sub-surface, including Green-Ampt, Horton, and Initial Loss/Continuing Loss. These methods are used to simulate hydrological losses, particularly when rainfall is applied directly to the 2D surface and runoff is generated.

The choice of infiltration method and its parameters is an important calibration factor and should be adjusted to match observed flow data. This is especially relevant for whole of catchment modelling, where infiltration is the main way hydrological losses are represented. This page describes the Green-Ampt infiltration parameters and their sensitivity.

== Green-Ampt Infiltration ==
The Green-Ampt approach varies the rate of infiltration over time based on the soil’s hydraulic conductivity, suction, porosity and initial moisture content. The method assumes that as water begins to infiltrate the soil, a line is developed differentiating between the ‘dry’ soil with moisture content θi and the ‘wet’ soil (with moisture content equal to the porosity of the soil η). As the infiltrated water continues to move through the soil profile in a vertical direction, the soil moisture changes instantly from the initial content to a saturated state. This concept is shown schematically in Figure 1.

Note: The Green-Ampt approach is appropriate for simulating single rainfall events where evapotranspiration and gravity-driven drainage are not significant. The 2023-03 release introduced functionality in TUFLOW HPC to allow for horizontal movement of soil water, enabling long-term simulations with multiple rainfall events. To support this, a change was implemented in the Green-Ampt equation to account for changing initial soil moisture and cumulative infiltration over time. For further details, see Section 7.3.7.1.1 Green-Ampt (GA) in the [https://docs.tuflow.com/classic-hpc/manual/2025.1/TwoD-Domains-1.html#GA-5 TUFLOW Manual].

[[File:Fig_1_GA_Model.png|300px|Figure 1 Green-Ampt Model Concept]] 

'''Figure 1 Green-Ampt Model Concept''' 
''Figure courtesy of University of Texas''

 
The basic form of the Green-Ampt equation is expressed as follows: 
[[File:Basic_ga_equation.png|200px]] 

 
Where: 
:''t'' is time 
:K is the saturated hydraulic conductivity 
:∆''θ'' is defined as the soil capacity (the difference between the saturated and initial moisture content) 
:''φ'' is the soil suction head 
:h0 is the depth of ponded water 
:F(t) is the cumulative infiltration calculated from: 
[[File:Accumulative_infil.png|350px]] 

United States Department of Agriculture (USDA) soil types have been hardwired into TUFLOW and are presented in Table 1 along with the soil parameters. Alternatively, it is possible to define a customised soil type by specifying user defined values within the tsoilf. 
 
'''Table 1 USDA Soil types for the Green-Ampt Infiltration Method (from Rawls, W, J, Brakesiek & Miller, N, 1983, ‘Green-Ampt infiltration parameters from soils data’, Journal of Hydraulic Engineering, vol 109, 62-71.)''' 
{| class="wikitable "
| '''USDA Soil Type''' || '''Suction (mm)''' || '''Hydraulic Conductivity (mm/hr)''' || '''Porosity (Fraction)'''
|-
| '''Clay''' || 316.3 || 0.3 || 0.385
|-
| '''Silty Clay''' || 292.2 || 0.5 || 0.423
|-
| '''Sandy Clay''' || 239 || 0.6 || 0.321
|-
| '''Clay Loam''' || 208.8 || 1 || 0.309
|-
| '''Silty Clay Loam''' || 273 || 1 || 0.432
|-
| '''Sandy Clay Loam''' || 218.5 || 1.5 || 0.33
|-
| '''Silt Loam''' || 166.8 || 3.4 || 0.486
|-
| '''Loam''' || 88.9 || 7.6 || 0.434
|-
| '''Sandy Loam''' || 110.1 || 10.9 || 0.412
|-
| '''Loamy Sand''' || 61.3 || 29.9 || 0.401
|-
| '''Sand''' || 49.5 || 117.8 || 0.417
|}
 
Table 2 presents summary statistics for the Green-Ampt USDA Parameters and typical values. This provides a good indication of the typical ranges of the Green-Ampt parameter values. 
 
'''Table 2 USDA Summary Statistics for all Soil types for the Green-Ampt Infiltration Method''' 
{| class="wikitable "
| '''Stat''' || '''Suction (mm)''' || '''Hydraulic Conductivity (mm/hr)''' || '''Porosity (Fraction)'''
|-
| '''Min''' || 49.5 || 0.3 || 0.31
|-
| '''Max''' || 316.3 || 117.8 || 0.49
|-
| '''Mean''' || 184.04 || 15.86 || 0.4
|-
| '''SD''' || 94.82 || 34.92 || 0.05
|}
 
In order to help those undertaking real world calibration of TUFLOW models to observed data, a sensitivity analysis of the various parameters have been undertaken to show the effect of each Green-Ampt parameter in isolation. The comparison has been undertaken on a real-world whole catchment model of the Plynlimon catchment in mid-Wales. The model was run with a real rainfall event from 2015 with a temporal resolution of 30 minutes as shown in Figure 2. 
 

[[File:Fig2 GWY RF.png|600px|Figure 2: Plynlimon Rainfall|border]] 

'''Figure 2: Plynlimon Rainfall''' 

For the purposes of this sensitivity analysis of the parameters, a single soil type was used representing the general clay soil types that are present. 

== Green-Ampt Infiltration: User Parameters ==
Where the inbuilt USDA soil types are not used, the user can specify their own values for the Suction, Hydraulic Conductivity, Porosity and Initial Soil Moisture. What follows is a description of each parameter and the sensitivity to a low, medium and high value based on the USDA soil type summary values.

=== Capillary Suction Head ===
The suction head, represented in millimeters, is the capillary attraction on the soil voids. It is large for fine grain soils such as clays and smaller for sandy soils. To test the sensitivity of the simulated runoff at a gauged location, a low (49.5mm), mid representing the mean (184.4mm) and high (316.3mm) value of the suction head parameter were used with other parameters representing a clay soil (soil type 1). 
The larger the value of the capillary suction head, the more capillary action that is achieved and the amount of infiltration that takes place. This is shown by the increase in cumulative infiltration in the graph below with a greater cumulative infiltration for the increase in the suction head. 

[[File:Fig4 sens to suction.png|600px|Figure 3: Sensitivity of cumulative infiltration in the Plynlimon Gwy catchment to the Capillary Suction Head parameter in the Green-Ampt infiltration model.|border]] 

'''Figure 3: Sensitivity of cumulative infiltration in the Plynlimon Gwy catchment to the Capillary Suction Head parameter in the Green-Ampt infiltration model.''' 
 
As a consequence of this, there is a less runoff generated as shown in Figure 4. As can be seen, the model is not particularly sensitive to the suction head parameter and this fits with observations made within the literature from other similar studies. 
 

[[File:Suction Head.jpg|border|760x760px|Figure 4: Sensitivity of simulated flow at the Cefn-Brwn gauge location in the Plynlimon Gwy catchment to the Suction head parameter in the Green-Ampt infiltration model.]] 

'''Figure 4: Sensitivity of simulated flow at the Cefn-Brwn gauge location in the Plynlimon Gwy catchment to the Suction head parameter in the Green-Ampt infiltration model.''' 
 
It can also be seen that the higher the suction head value that the longer it takes the hydrograph to start rising, with the high suction head scenario less responsive to the rainfall.

=== Saturated Hydraulic Conductivity ===
The saturated hydraulic conductivity, measured in millimetres per hour, represents how easily water can travel through soil when fully saturated. In the Horton infiltration model, this value corresponds to the limiting infiltration rate. Hydraulic conductivity is typically high for sandy soils and low for compact clays.

In the sensitivity testing, the focus was on clay soils, which generally have low conductivity values. Three scenarios were initially tested: low (0.3 mm/hr), mid (15.86 mm/hr), and high (117.8 mm/hr). However, the mid and high values resulted in such high infiltration that no surface runoff was produced, leading to zero simulated flow at the downstream gauge location. As expected, increasing hydraulic conductivity leads to more infiltration and less runoff, a relationship well documented in Green-Ampt-based infiltration modelling.

To improve the analysis, it is recommended that the model be rerun using a refined range of lower conductivity values that still allow some runoff, such as 0.3, 1.0, 3.4, and 7.6 mm/hr. This would provide a more meaningful understanding of the parameter sensitivity while preserving realistic surface runoff behaviour. 
 

[[File:Hydraulic Conductivity.jpg|border|760x760px|Figure 5: Sensitivity of simulated flow at the Cefn-Brwn gauge location in the Plynlimon Gwy catchment to the Saturated Hydraulic Conductivity parameter in the Green-Ampt infiltration model when using a clay soil type.]] 

'''Figure 5: Sensitivity of simulated flow at the Cefn-Brwn gauge location in the Plynlimon Gwy catchment to the Saturated Hydraulic Conductivity parameter in the Green-Ampt infiltration model when using a clay soil type.''' 
 

[[File:Fig7 hydroconduct.png|600px|Figure 6: Sensitivity of cumulative infiltration in the Plynlimon Gwy catchment to the Saturated Hydraulic Conductivity parameter in the Green-Ampt infiltration model.|border]] 

'''Figure 6: Sensitivity of cumulative infiltration in the Plynlimon Gwy catchment to the Saturated Hydraulic Conductivity parameter in the Green-Ampt infiltration model.'''

=== Porosity ===
The porosity value represents the volume of dry voids per volume of soil and provides the maximum moisture deficit that is available, the difference between the moisture content at saturation and at the start of the simulation. Sandy soils tend to have lower porosities than clay soils, but drain to lower moisture contents between rainfall events because water is not held as strongly in the soil pores. Therefore, values of porosity tend to be higher for sandy soils when compared to clay soils. As shown in figure 7, the higher the porosity value, then the less runoff that is generated due to increased infiltration although the model is not particular sensitive to the porosity value. 
 

[[File:Porosity.jpg|border|760x760px|Figure 7: Sensitivity of simulated flow at the Cefn-Brwn gauge location in the Plynlimon Gwy catchment to the porosity parameter in the Green-Ampt infiltration model.]] 

'''Figure 7: Sensitivity of simulated flow at the Cefn-Brwn gauge location in the Plynlimon Gwy catchment to the porosity parameter in the Green-Ampt infiltration model.''' 
 

[[File:Fig8 porosity sens.png|600px|Figure 8: Sensitivity of cumulative infiltration in the Plynlimon Gwy catchment to the porosity parameter in the Green-Ampt infiltration model.|border]] 

'''Figure 8: Sensitivity of cumulative infiltration in the Plynlimon Gwy catchment to the porosity parameter in the Green-Ampt infiltration model.''' 

=== Initial Moisture ===
The initial moisture value represents the fraction of the soil that is initially wet. As both initial moisture and porosity are expressed as fractions, the soil capacity is defined as the difference between them both. As such, the initial moisture should not exceed the porosity otherwise soil capacity will be set to zero with no infiltration occurring for that soil type. A [[TUFLOW Message 2508 |2508 WARNING]] is issued if this is the case. 

As you increase initial moisture at the beginning of your simulation, you experience less infiltration (as you are closer to the soil capacity), therefore have more run-off and a quicker response. Figure 9 shows the degree of change to cumulative infiltration with varying initial moisture and the effect on the catchment can be seen in Figure 10. As the event progresses, soils become more saturated and the influence of the initial moisture parameter becomes less significant.

[[File:Init moisture F10.png|600px|Figure 9: Sensitivity of cumulative infiltration in the Plynlimon Gwy catchment to the initial moisture parameter in the Green-Ampt infiltration model.|border]] 
'''Figure 9: Sensitivity of cumulative infiltration in the Plynlimon Gwy catchment to the initial moisture parameter in the Green-Ampt infiltration model.''' 
[[File:Initial moisture.jpg|border|760x760px|Figure 10: Sensitivity of simulated flow at the Cefn-Brwn gauge location in the Plynlimon Gwy catchment to the initial moisture parameter in the Green-Ampt infiltration model.]] 
'''Figure 10: Sensitivity of simulated flow at the Cefn-Brwn gauge location in the Plynlimon Gwy catchment to the initial moisture parameter in the Green-Ampt infiltration model.'''

=== Max Ponding Depth ===
The max ponding depth value is an optional value that can be used, if desired, to set a limit for the depth of ponded water (h0) value used in the Green-Ampt equation. The minimum of the water depth and the max ponding depth value is used as the h0 value. The default max ponding depth value is 0, to be consistent with the basic form of the Green-Ampt equation, as hydrology models do not necessarily have a depth calculated at cells.

This means, if using a max ponding depth (>0), infiltration rates will increase.

== In built USDA soil type ==
The model was also run with the default in-build USDA soil types. Figure 11 shows the outputs. As expected the higher the soil type, then typically the more the infiltration and the lower the produced runoff. Soils 8-11, which represent sandy soils do not show any runoff in this example as the rainfall applied directly to the mesh is all infiltrated. 
 
[[File:Soil Type.jpg|border|760x760px|Figure 11: Sensitivity of simulated flow at the Cefn-Brwn gauge location in the Plynlimon Gwy catchment to the USDA soil type parameter in the Green-Ampt infiltration model.]] 
'''Figure 11: Sensitivity of simulated flow at the Cefn-Brwn gauge location in the Plynlimon Gwy catchment to the USDA soil type parameter in the Green-Ampt infiltration model.'''

== Summary ==
The Green-Ampt infiltration model is one of the infiltration methods available within TUFLOW. There is extensive literature on its application, including suggested parameter values for various soil types, though these are mostly based on soils in the United States.

Three main Green-Ampt parameters have been tested to assess the sensitivity of model outputs to parameter values and variations in initial soil moisture. The results show that the model is relatively insensitive to the porosity and suction head parameters. However, outputs show significant variations in runoff volume in response to changes in hydraulic conductivity.

As part of any calibration process, it is recommended that hydraulic conductivity and initial moisture content be prioritised during calibration. Hydraulic conductivity influences runoff volume throughout the event, while initial soil moisture mainly affects the early part of the simulation until soils become saturated and results converge.

==Acknowledgements==

The Plynlimon model contains data supplied by Natural Environment Research Council. The Plynlimon observed rain gauge and flow data was provided by the Centre of Hydrology, Bangor. The model uses LiDAR data which is public sector information licensed under the Open Government Licence v3.0.

File:Initial moisture.jpg

2026-01-15T14:06:42Z

Tuflowduncan:

Sensitivity to Initial Moisture

File:Soil Type.jpg

2026-01-15T14:06:12Z

Tuflowduncan:

USDA Soil Type Sensitivity

File:Porosity.jpg

2026-01-15T14:05:33Z

Tuflowduncan:

Porosity Sensitivity

File:Hydraulic Conductivity.jpg

2026-01-15T14:05:00Z

Tuflowduncan:

Hydraulic Conductivity Sensitivity

File:Suction Head.jpg

2026-01-15T14:03:52Z

Tuflowduncan:

Suction Head Sensitivity

InfoWorks ICM to TUFLOW

2026-01-06T12:53:09Z

Tuflowduncan: /* Quick Export of Geometry Data */

'''Page In Progress'''

=Introduction=
This page outlines an approach for conversion of an InfoWorks ICM model to an Estry/TUFLOW format so that the 1D and 2D networks can be replicated in TUFLOW and used to generate a TUFLOW model. 

=InfoWorks ICM Network Conversion=

The InfoWorks data formats are native and therefore do require access to InfoWorks in order to convert the data. Note, that the following steps can be undertaken with a InfoWorks ICM Viewer licence and a full licence is not currently required.
Although the InfoWorks ICM data formats are proprietry, it is relatively easy to use the Open Data Export Centre within InfoWorks ICM to export the model geometry data to open GIS layer formats (both shapefile and MIF/MID format). The following steps will outline exporting to shapefiles but similar can be undertaken for MIF/MID.
To open the Open Data Export Centre in InfoWorks ICM, open your network in the geoplan, select the relevant scenario, and go to '''Network->Export->Using Open Data Export Centre'''. You’ll be presented with the following dialog which allows you to export the InfoWorks network data to a variety of formats.

[[File:ODEC.png|400px]]

The data in InfoWorks ICM is stored in a number of database tables for each network type (eg, a separate table for nodes, conduits, 2D zones etc…).

==Quick Export of Geometry Data==

To get a full export of all the model files, with InfoWorks file formats, open the network and go to '''Network->Export->to Shape Files''', select the save location and the InfoWorks tables that you're interested in. Once exported the shape files can be opened in GIS to view the network table geometry and parameters. Once the data is exported, it's possible to use the QGIS TUFLOW Plugin 'Insert TUFLOW Attributes to Existing GIS Layer' and then map across the field values from InfoWorks to TUFLOW with conversion as required.

A Ruby script is also available which will export export all data via the Open Data Export Centre without the need for the user to export each table individually. The data can use a config file to undertake some of the mapping of field values and some conversion.

==Use of Ruby Scripts==

It’s possible to utilise the Ruby Scripting interface within InfoWorks ICM to speed up the export. A ruby script can be run to call the Open Data Export Centre, and export all requested tables, using a specified config file automatically, significantly reducing the number of button clicks. An example Ruby Script is available from [https://gitlab.com/tuflow-user-group/tuflow/model-conversions/infoworks-icm TUFLOW Gitlab User Group] which exports all tables and data in an InfoWorks format.

To run the script, you’ll again need to run InfoWorks ICM with a viewer licence or greater. With the desired network in the geoplan, go to '''Network->Run Ruby Script'''. Navigate to and select the ruby script, in the below this is ICM_Out_to_shp_1.rb.

[[File:Ruby.png|400px]]

The script will then begin running and prompt the user to select a config file. Navigate and select the relevant config file.

[[File:Config.png|400px]]

The user will then be prompted where they would like to export the data too. Select an appropriate file directory. The ruby script will then cycle through the list of tables within the script and export the tables automatically. Once complete the script will return a log highlighting the location of the exported files. All network objects are exported regardless of system type. System type is exported as an additional field in the shape files to enable filtering within GIS as required.

[[File:Ruby log message.png|400px]]

The exported shape files can then be opened in GIS for further inspection and once checked can be linked together using the various TUFLOW control files. A set of generic control files for this are in progress.

'''InfoWorks ICM Network''' 
[[File:ICM network.png|400px]]

'''TUFLOW Network''' 
[[File:TUFLOW network.png|400px]]

=Exporting Real Time Control=
Operational Control is referred to as Real Time Control (RTC) in InfoWorks. The ruby script above will export the RTC as a text file called [Network_Name]_ICM_RTC.txt which can be used as the basis to generate the TUFLOW Operational Control file. The RTC is made up of the object that is being controlled, the defined ranges in which the structure operates and the desired operation. For example in the below example, the sluice gate, Storm1_Chamber.1, will be set to an 'On' position of 0.2m if the height above datum at FORAST_CSO is below 32.3m AD and will be set to an 'Off' position of 0m if the water level is above 32.3m AD.

[[File:RTC.PNG]]

This can be written using TUFLOW Operation Control rules as the following:-

<tt>Define Sluice </tt> <tt>==</tt> Storm1_Chamber.1
WSE <tt>==</tt> H1D FORAST_CSO
<tt>IF</tt> WSE < 32.3
Gate Opening <tt>==</tt> 0.2
<tt>ELSE</tt>
Gate Opening <tt>==</tt> 0
<tt>END IF</tt>

=Exporting Boundary Conditions=

Inflow, level and rainfall boundaries are all held in separate database objects within InfoWorks. These can be exported directly to .csv file format which can then be modified to put it into a TUFLOW format and a bc_dbase file generated to relate the time-varying data to the relevant model node.

'''InfoWorks ICM Rainfall Time-Varying Data''' 
[[File:ICM Boundary data.png|400px]]

'''TUFLOW Rainfall Boundary Time-Varying Data''' 
[[File:TUFLOW Boundary data.png|400px]]

=Exporting a Gridded Ground model=

Within InfoWorks, select the gridded ground model, right click and choose '''Export->to ESRI ASCII grid files'''. This will export into a file format that can be directly used within TUFLOW.

=Other Considerations=

*Shapefile limitations mean that field names and values can only be 11 characters long. This can mean that some node ids and other information is truncated. This is reported in the error reporting.
 
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Flood Modeller Tutorial Model

2026-01-06T08:21:59Z

Tuflowduncan: /* Requirements and Downloads */

=Introduction=
The objective of the Flood Modeller - TUFLOW modules is to demonstrate how TUFLOW links to the external Flood Modeller 1D scheme and the methods available to create this link. They are designed to supplement existing documentation and assume prior knowledge of both Flood Modeller and TUFLOW software packages.

These modules were developed by BMT in collaboration with Jacobs. Comments, requests and feedback can be sent to [mailto:support@tuflow.com support@tuflow.com].

=Requirements and Downloads=
Both TUFLOW and Flood Modeller have modest system requirements for small models such as those used in these modules. Larger and more complex models, however, may require higher hardware specifications, particularly memory (RAM). The tutorial models are intentionally small to ensure quick simulation and load times, and should run on any modern PC or laptop capable of running Windows 10 or later.

TUFLOW models typically require access to a GIS package, a text editor, Microsoft Excel and a results viewer to build, review and visualise a model. A list of compatible packages is available on the TUFLOW Wiki. Flood Modeller can also be used as a graphical user interface for creating and editing GIS layers in a TUFLOW model, as well as for visualising results.

Instructions for Flood Modeller - TUFLOW modules are provided using the following GIS file formats:

* '''QGIS - SHP'''

* '''QGIS - GPKG'''

{| class="wikitable" width="75%"

! style="background-color:#005581; font-weight:bold; color:white;"| Requirement
! style="background-color:#005581; font-weight:bold; color:white;" | Brief Description
! style="background-color:#005581; font-weight:bold; color:white;" | Download
|-

| '''TUFLOW''' || TUFLOW is a computer program for simulating depth-averaged, one dimensional free-surface flows such as occurs from floods and tides, with the 2D solution occurring over a regular grid of square elements. 

It is commonly used in the UK and Ireland, Australia and the United States for the modelling of surface waters, river systems and pipe networks. 

It is recommended to always use the latest release version of TUFLOW. 

This tutorial model does not require a TUFLOW licence. 

This tutorial is set up to use a NVIDIA GPU card. If this is not available, CPU can be specfied within the [https://docs.tuflow.com/classic-hpc/manual/2025.2/TCFCommands-1.html#tcfHardware Hardware] command. 
||The TUFLOW executable is provided within the [https://wiki.tuflow.com/Tutorial_Introduction#Module_Data Tutorial Dataset].
|-

|'''Flood Modeller'''|| Flood Modeller (previously known as ISIS) is a commercial flood modelling package developed by Jacobs for simulating depth-averaged one and two dimensional free surface flows. It is primarily used for the simulation of river channels and is widely used within the UK and Ireland. This tutorial model will only leverage Flood Modeller’s 1D Solver. 
TUFLOW 1D and 2D domains can be dynamically linked to the 1D domain of Flood Modeller. Flood Modeller is not included within the TUFLOW executable and must be downloaded separately. 

Unlike TUFLOW Flood Modeller has a standalone Graphical User Interface which can be used to build networks, run models, and visualise results.

It is recommended that TUFLOW 2023-03-AA or later is used in conjunction with Flood Modeller Version 5 or later. [https://docs.tuflow.com/classic-hpc/manual/2025.2/OneD2DLinkingFM-2.html#fig:fig-FMTUFLOWVersionCompatability Figure 10.15] of the [https://docs.tuflow.com/classic-hpc/manual/2025.2/ 2025 TUFLOW manual] provides a list of compatibility between recent Flood Modeller and TUFLOW versions. 

For Flood Modeller Version 5 or later a Standard, Professional, or Unlimited Edition of Flood Modeller Pro is required to open and run the tutorial model.
||[https://www.floodmodeller.com/downloads/ Latest 64-bit version of Flood Modeller]. 
|-
| '''QGIS''' QGIS TUFLOW plugin || A Geographic Information System (GIS) used to build models and view results. This tutorial was developed with QGIS 3.20. It is recommended to have QGIS 3.20 or later to ensure compatibility with TUFLOW plugin latest features. 

The TUFLOW plugin includes numerous tools to increase workflow efficiency. 

||[https://qgis.org/download/ Latest 64-bit version of QGIS]. 

[[TUFLOW_QGIS_Plugin| QGIS TUFLOW Plugin Installation]].
|-
| '''NotePad++''' Syntax Highlighting || A text editor is required for creation of the TUFLOW input files. This tutorial was developed with NotePad++. Ideally a text editor should be able to: 
*Colour code the TUFLOW control files;
*Open other files from the active control file; and
*Launch a TUFLOW simulation. 
TUFLOW colour coding can be enabled using syntax highlighting.
|| [https://notepad-plus-plus.org/downloads/ Latest 64-bit version of Notepad++]. 

[https://downloads.tuflow.com/_archive/Miscellaneous/NPP_TUFLOW_Syntax_Highlighting.zip TUFLOW syntax highlighting for Notepad++]. For instructions on configuring Notepad++ for TUFLOW modelling, see [[NotepadPlusPlus_Tips |Notepad++ tips]].
|-
| '''Microsoft Excel''' || A spreadsheet software is required for working with tabular data and .csv files. This tutorial has been created in Excel. ||
|}
=Module Data=
To build the tutorial model, download one of the datasets below. This includes a digital elevation model (DEM), aerial photography, background model data for the tutorial model and a working version of the model. There are two formats available, Shapefile and GeoPackage. The GeoPackage format has been supported since the TUFLOW 2023-03 Release, for tips on its use see [https://wiki.tuflow.com/GeoPackage_Tips GeoPackage Tips].
*[https://downloads.tuflow.com/_archive/TUFLOW/Tutorial_Model/QGIS_SHP_FMP_Tut_Model.zip QGIS SHP Download]
*[https://downloads.tuflow.com/_archive/TUFLOW/Tutorial_Model/QGIS_GPKG_FMP_Tut_Model.zip QGIS GPKG Download]
If would you like to download the tutorial model datasets for ArcGIS or MapInfo, these can be found on the [[Flood_Modeller_Tutorial_Model_Archive | Archive Page]].

=Recommended Reading=
The aim of this tutorial is to demonstrate the steps undertaken to build, review and visualise the results of a linked Flood Modeller – TUFLOW model. It assumes that the user has a good understanding of both the 1D component of Flood Modeller and the 1D and 2D components of TUFLOW. The following resources may be of use:
*[[Tutorial_Introduction |TUFLOW Tutorial Model]]
*[https://docs.tuflow.com/classic-hpc/manual/2025.2/ TUFLOW Classic / HPC User Manual]
*[https://help.floodmodeller.com/docs/getting-started-with-1d-river-modelling Flood Modeller 1D Quick Start Guide]
*[https://help.floodmodeller.com/docs/technical-reference Flood Modeller Technical Reference]

=Modules=
The tutorial is presented over a series of modules, with each module offering the opportunity to run the model and review the results. Each of the modules builds upon the previous iteration with models developed in the previous module made available.

New users are advised to undertake the modules in sequence, whilst more experienced users can skip to modules containing specific features of interest. Results and check files are not included to keep the size of the download file manageable, but can be generated through the running of the simulations. The folder should be placed in a location with write permissions. The first tutorial module introduces the user to the linking of a TUFLOW 2D domain to a 1D Flood Modeller model. From this tutorial you will learn how to link an existing Flood Modeller 1D model to a TUFLOW 2D domain. This tutorial is ideal for those starting to learn how to link Flood Modeller and TUFLOW.

:*[[ Flood_Modeller_Tutorial_Module01 | Flood Modeller Module 1]] - Linking Flood Modeller to TUFLOW

The second tutorial demonstrates the linking of an ESTRY pipe network to an existing Flood Modeller – TUFLOW linked model. From this tutorial you will learn how to add a 1D pipe network and connect it to the representation of the watercourse created in Flood Modeller and link it to the TUFLOW representation of the floodplain created as part of the first tutorial. The second tutorial is ideal for those who would like to learn more about the interaction of TUFLOW with Flood Modeller including the simulation of fully integrated drainage systems.
:*[[ Flood_Modeller_Tutorial_Module02 | Flood Modeller Module 2]] - Linking Flood Modeller to ESTRY

 
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Flood Modeller Tutorial Model

2026-01-06T08:20:17Z

Tuflowduncan: /* Requirements and Downloads */

=Introduction=
The objective of the Flood Modeller - TUFLOW modules is to demonstrate how TUFLOW links to the external Flood Modeller 1D scheme and the methods available to create this link. They are designed to supplement existing documentation and assume prior knowledge of both Flood Modeller and TUFLOW software packages.

These modules were developed by BMT in collaboration with Jacobs. Comments, requests and feedback can be sent to [mailto:support@tuflow.com support@tuflow.com].

=Requirements and Downloads=
Both TUFLOW and Flood Modeller have modest system requirements for small models such as those used in these modules. Larger and more complex models, however, may require higher hardware specifications, particularly memory (RAM). The tutorial models are intentionally small to ensure quick simulation and load times, and should run on any modern PC or laptop capable of running Windows 10 or later.

TUFLOW models typically require access to a GIS package, a text editor, Microsoft Excel and a results viewer to build, review and visualise a model. A list of compatible packages is available on the TUFLOW Wiki. Flood Modeller can also be used as a graphical user interface for creating and editing GIS layers in a TUFLOW model, as well as for visualising results.

Instructions for Flood Modeller - TUFLOW modules are provided using the following GIS file formats:

* '''QGIS - SHP'''

* '''QGIS - GPKG'''

{| class="wikitable" width="75%"

! style="background-color:#005581; font-weight:bold; color:white;"| Requirement
! style="background-color:#005581; font-weight:bold; color:white;" | Brief Description
! style="background-color:#005581; font-weight:bold; color:white;" | Download
|-

| '''TUFLOW''' || TUFLOW is a computer program for simulating depth-averaged, one dimensional free-surface flows such as occurs from floods and tides, with the 2D solution occurring over a regular grid of square elements. 

It is commonly used in the UK and Ireland, Australia and the United States for the modelling of surface waters, river systems and pipe networks. 

It is recommended to always use the latest release version of TUFLOW. 

This tutorial model does not require a TUFLOW licence. 

This tutorial is set up to use a NVIDIA GPU card. If this is not available, CPU can be specfied within the [https://docs.tuflow.com/classic-hpc/manual/2025.2/TCFCommands-1.html#tcfHardware Hardware] command. 
||The TUFLOW executable is provided within the [https://wiki.tuflow.com/Tutorial_Introduction#Module_Data Tutorial Dataset].
|-

|'''Flood Modeller'''|| Flood Modeller (previously known as ISIS) is a commercial flood modelling package developed by Jacobs for simulating depth-averaged one and two dimensional free surface flows. It is primarily used for the simulation of river channels and is widely used within the UK and Ireland. This tutorial model will only leverage Flood Modeller’s 1D Solver. 
TUFLOW 1D and 2D domains can be dynamically linked to the 1D domain of Flood Modeller. Flood Modeller is not included within the TUFLOW executable and must be downloaded separately. 

Unlike TUFLOW Flood Modeller has a standalone Graphical User Interface which can be used to build networks, run models, and visualise results.

It is recommended that TUFLOW 2020-10-AD or later is used in conjunction with Flood Modeller Version 5 or later. [https://docs.tuflow.com/classic-hpc/manual/2025.2/OneD2DLinkingFM-2.html#fig:fig-FMTUFLOWVersionCompatability Figure 10.15] of the [https://docs.tuflow.com/classic-hpc/manual/2025.2/ 2025 TUFLOW manual] provides a list of compatibility between recent Flood Modeller and TUFLOW versions. 

For Flood Modeller Version 5 or later a Standard, Professional, or Unlimited Edition of Flood Modeller Pro is required to open and run the tutorial model.
||[https://www.floodmodeller.com/downloads/ Latest 64-bit version of Flood Modeller]. 
|-
| '''QGIS''' QGIS TUFLOW plugin || A Geographic Information System (GIS) used to build models and view results. This tutorial was developed with QGIS 3.20. It is recommended to have QGIS 3.20 or later to ensure compatibility with TUFLOW plugin latest features. 

The TUFLOW plugin includes numerous tools to increase workflow efficiency. 

||[https://qgis.org/download/ Latest 64-bit version of QGIS]. 

[[TUFLOW_QGIS_Plugin| QGIS TUFLOW Plugin Installation]].
|-
| '''NotePad++''' Syntax Highlighting || A text editor is required for creation of the TUFLOW input files. This tutorial was developed with NotePad++. Ideally a text editor should be able to: 
*Colour code the TUFLOW control files;
*Open other files from the active control file; and
*Launch a TUFLOW simulation. 
TUFLOW colour coding can be enabled using syntax highlighting.
|| [https://notepad-plus-plus.org/downloads/ Latest 64-bit version of Notepad++]. 

[https://downloads.tuflow.com/_archive/Miscellaneous/NPP_TUFLOW_Syntax_Highlighting.zip TUFLOW syntax highlighting for Notepad++]. For instructions on configuring Notepad++ for TUFLOW modelling, see [[NotepadPlusPlus_Tips |Notepad++ tips]].
|-
| '''Microsoft Excel''' || A spreadsheet software is required for working with tabular data and .csv files. This tutorial has been created in Excel. ||
|}
=Module Data=
To build the tutorial model, download one of the datasets below. This includes a digital elevation model (DEM), aerial photography, background model data for the tutorial model and a working version of the model. There are two formats available, Shapefile and GeoPackage. The GeoPackage format has been supported since the 2023-03 Release, for tips on its use see [https://wiki.tuflow.com/GeoPackage_Tips GeoPackage Tips].
*[https://downloads.tuflow.com/_archive/TUFLOW/Tutorial_Model/QGIS_SHP_FMP_Tut_Model.zip QGIS SHP Download]
*[https://downloads.tuflow.com/_archive/TUFLOW/Tutorial_Model/QGIS_GPKG_FMP_Tut_Model.zip QGIS GPKG Download]
If would you like to download the tutorial model datasets for ArcGIS or MapInfo, these can be found on the [[Flood_Modeller_Tutorial_Model_Archive | Archive Page]].

=Recommended Reading=
The aim of this tutorial is to demonstrate the steps undertaken to build, review and visualise the results of a linked Flood Modeller – TUFLOW model. It assumes that the user has a good understanding of both the 1D component of Flood Modeller and the 1D and 2D components of TUFLOW. The following resources may be of use:
*[[Tutorial_Introduction |TUFLOW Tutorial Model]]
*[https://docs.tuflow.com/classic-hpc/manual/2025.2/ TUFLOW Classic / HPC User Manual]
*[https://help.floodmodeller.com/docs/getting-started-with-1d-river-modelling Flood Modeller 1D Quick Start Guide]
*[https://help.floodmodeller.com/docs/technical-reference Flood Modeller Technical Reference]

=Modules=
The tutorial is presented over a series of modules, with each module offering the opportunity to run the model and review the results. Each of the modules builds upon the previous iteration with models developed in the previous module made available.

New users are advised to undertake the modules in sequence, whilst more experienced users can skip to modules containing specific features of interest. Results and check files are not included to keep the size of the download file manageable, but can be generated through the running of the simulations. The folder should be placed in a location with write permissions. The first tutorial module introduces the user to the linking of a TUFLOW 2D domain to a 1D Flood Modeller model. From this tutorial you will learn how to link an existing Flood Modeller 1D model to a TUFLOW 2D domain. This tutorial is ideal for those starting to learn how to link Flood Modeller and TUFLOW.

:*[[ Flood_Modeller_Tutorial_Module01 | Flood Modeller Module 1]] - Linking Flood Modeller to TUFLOW

The second tutorial demonstrates the linking of an ESTRY pipe network to an existing Flood Modeller – TUFLOW linked model. From this tutorial you will learn how to add a 1D pipe network and connect it to the representation of the watercourse created in Flood Modeller and link it to the TUFLOW representation of the floodplain created as part of the first tutorial. The second tutorial is ideal for those who would like to learn more about the interaction of TUFLOW with Flood Modeller including the simulation of fully integrated drainage systems.
:*[[ Flood_Modeller_Tutorial_Module02 | Flood Modeller Module 2]] - Linking Flood Modeller to ESTRY

 
{{Tips Navigation
|uplink=[[Main_Page| Back to Main Page]]
}}

Groundwater Modelling Advice

2025-12-03T14:56:16Z

Tuflowduncan: /* Python */

= Introduction =
From the 2023-03 release and onwards, horizontal flow (advection) of water and multiple vertical groundwater layers when using TUFLOW HPC are supported. This page provides useful groundwater modelling advice to users.

= Groundwater Linking to 1D (ESTRY or SWMM) =
Since the 2025.2.0 release, TUFLOW supports connecting the 1D domain (either ESTRY or SWMM) to 2D groundwater layers. This enables users to model features such as detention basins with subsurface drainage or other green infrastructure directly within a TUFLOW model and represent groundwater and surface water impacts. The physical infrastructure collecting the groundwater varies, but is typically a perforated or slotted pipe in loose fill such as gravel or sand.

The discharge through the connection is typically modeled using a depth vs discharge curve where the depth applied is the pressure in the groundwater at the location of the connection. This relationship is often defined using the orifice equation where the orifice coefficient depends on the configuration. This section below contains guidance for generating a curve based on the orifice equation.

== Depth vs Discharge Curves ==
This section provides two methods for generating depth vs discharge curves based on the orifice equation: 

[[File: orifice_equation.png]] 
Where:
*'''''CdA''''' is the orifice coefficient
:*'''''Cd''''' is the discharge coefficient
:*'''''A''''' is the cross-sectional area of the orifice
*'''''Hup''''' is the upstream water level
*'''''Hdown''''' is the higher of the downstream obvert or downstream water level 

The following link provides some guidance on how to select the orifice coefficient: https://wiki.sustainabletechnologies.ca/wiki/Flow_through_perforated_pipe

=== Python ===
The following python code, also available [https://gitlab.com/tuflow-user-group/tuflow/data-pre-processing/orifice_depth_discharge/-/blob/main/Orifice_Depth_Discharge_Curve.py here], can be used to generate depth vs discharge curves, which can then be input into a model with groundwater linking to 1D.

'''import''' math 
'''import''' numpy '''as''' np 
gravity_metric = '''9.81 '''# Metric Units: m/s^2
gravity_us_customary = '''32.2 '''# US Customary Units: ft/s^2 
'''def''' generate_orifice_depth_vs_discharge(us_units, orifice_coefficient, depth_max, depth_step, output_filename):
 gravity = gravity_us_customary '''if''' us_units '''else''' gravity_metric 
 depths = np.arange('''0.0''', depth_max, depth_step)
 vec_func = np.vectorize('''lambda''', e: orifice_coefficient * math.sqrt('''2''' * gravity * e))
 discharges = vec_func(depths) 
 values = np.column_stack((depths, discharges)) 
 np.savetxt(output_filename, values, delimiter=",", fmt="%.7g", header='Depth, Discharge', comments=<nowiki>''</nowiki>) 
'''if''' __name__ == "__main__":
 use_us_units = False
 orifice_coefficent_value = 0.002 # Orifice coefficient
 depth_max_value = 2.0 # Maximum depth (in meters or feet)
 depth_step_value = 0.02 # Value to increment by (in meters or feet) 
 out_filename = "orifice_depth_vs_discharge.csv" 
 generate_orifice_depth_vs_discharge(use_us_units, orifice_coefficent_value, depth_max_value, depth_step_value, out_filename)

=== Excel ===
The following excel file can be used to generate depth vs discharge curves, which can then be input into a model with groundwater linking to 1D. The file contains a two examples, one for Metric and one for US Customary.

[https://downloads.tuflow.com/Private_Download/depth_vs_discharge.xlsx Depth vs Discharge - Excel]

= Common Questions Answered (FAQ) =

== What are the benefits of integrating groundwater modelling into flood simulations? ==
The addition of a groundwater model accounts for the attenuation of the rainfall-runoff response and the discharge of soil water to creeks. This helps in long-term simulations by generating base flow to the surface runoff, and helps predict the infiltration capacity for subsequent rainfall events by tracking the long term change in soil moisture. For examples of real world applications, please see:
* Australian Water School Webinar on [https://www.tuflow.com/library/webinars/#dec2024_groundwater_modelling TUFLOW Groundwater Flow Modelling and its Application]
* 2024 Enhancing Catchment Runoff Simulations Using Soil Moisture Dependent Hydraulic Conductivity, Gao et al, HWRS. [https://www.tuflow.com/media/8855/2024-enhancing-catchment-runoff-simulations-using-soil-moisture-dependent-hydraulic-conductivity-gao-et-al-errata.pdf link]
* 2023 Continuous Direct Rainfall Hydraulic Modelling with Coupled Surface Ground Water Interaction, Gao et al, HWRS. [https://www.tuflow.com/media/8523/2023-continuous-direct-rainfall-hydraulic-modelling-with-coupled-surface-ground-water-interaction-gao-et-al-hwrs.pdf link]

== How can a gravel trench be represented if it does not allow infiltration but connects two attenuation basins and intercepts runoff? ==
If the gravel trench does not allow infiltration but acts as a conveyance feature, it can be represented as a 1D channel or pipe to connect the two attenuation basins.

The groundwater functionality can be used by setting the surface infiltration rate as zero to model the lateral movement through the trench only. 2D cells with non-zero infiltration rate are still needed to infiltrate the surface water to the soil layer. However, soil water can discharge to the surface if the soil layer becomes full at the zero infiltration cells (TUFLOW does not put a 'lid' on soil surface). This approach is not recommended if the gravel trench is expected to become full.

== How should the Initial Loss/Continuing Loss (ILCL) infiltration method be applied, and are there standard values for different land cover types? ==
To use ILCL infiltration, the Soil ID must be defined in the model, either globally or spatially using a 2d_soil layer, which is read into the tgc file with the <tt>Read GIS Soil</tt> command. The 2d_grd check file can be used to confirm that the correct Soil IDs have been applied across the model.

TUFLOW does not provide standard IL/CL values, but values may be estimated from databases such as the CSIRO Soil Atlas. ARR Book 9, Section 6.4.2 offers general guidance for rainfall loss values, but this is separate from ILCL soil infiltration.

== Can water exfiltrate from subsurface layers other than the top layer? ==
Water can move both horizontally within a soil layer and vertically between layers. Downward flow is controlled by convective hydraulic conductivity (CO), while upward flow occurs through surcharging.

== How can permeable pavements be modelled? ==
Permeable pavements can be represented using soil layers. The simplest approach is to define infiltration using a 2d_soil layer, assigning a Soil ID with infiltration properties matching permeable pavements. This method removes infiltrated water from the model. If groundwater movement is important, multiple soil layers can be used to model horizontal flow and subsurface drainage.

== How should peat soils be represented in a direct rainfall model? ==
If observed flow data is available, calibrating the model to these measurements would be the best approach. If not, using a lumped hydrology model as a comparison for flow estimates is recommended. Since peat is often saturated, infiltration rates may be low, but lateral water movement could still occur. In this case, using the interflow functionality in TUFLOW may help better represent water movement within the catchment.

== How can a French drain (filter drain) be represented? ==
There is no direct method for modelling a French drain in TUFLOW, but there are a few possible approaches.

* One option is to drain water directly from surface cells using 1D pit.
* In TUFLOW 2025.2.0 version and later, 2D groundwater layers can also be connected to the 1D domain using SX BC.
In the 2 methods above, it's required to use Darcy’s law to estimate discharge rates and create a depth vs discharge curves.
* Alternatively, the model cell size can be reduced to the trench width to conduct localised modelling of the subsurface flow through the drain. The modelling result can be used to estimate infiltration rates to connect 1D and 2D (surface or subsurface) in a model with larger cell size and larger extent.

== How do soil parameters like thickness and hydraulic conductivity impact groundwater modelling? ==
Soil thickness and hydraulic conductivity control how water moves through the ground in TUFLOW’s groundwater modelling.

In general, a thicker soil layer increases soil capacity and has a greater ability to attenuate surface runoff during floods. A thicker soil layer also contributes to the continuous release of baseflow when it isn’t raining.

Hydraulic conductivity controls how easily water flows due to the gravity drain. During a flood event, vertical hydraulic conductivity determines the rate of infiltration from soil surface or from the soil layer above. Horizontal hydraulic conductivity affects the lateral movement of groundwater towards the bottom of the hillslope. A higher horizontal hydraulic conductivity increases the groundwater discharge to creek and produces more baseflow, which also frees up the soil capacity faster for the next rainfall event.

These factors are investigated in detail by this HWRS paper [https://www.tuflow.com/media/8523/2023-continuous-direct-rainfall-hydraulic-modelling-with-coupled-surface-ground-water-interaction-gao-et-al-hwrs.pdf Gao et al. 2023]

== How is total volume in and infiltration loss reported, and how can they be separated? ==
TUFLOW reports total volume in using multiple components, including rainfall, inflows, and other sources. The infiltration losses are reported in the HPC mass balance CSV file (MB_HPC.csv). However, it is subtracted from the "S/RF Vol In" value if the rainfall rate is larger than the infiltration rate, and is reported as "S/RF Vol Out" value if the infiltration rate is higher than rainfall rate. In addition, this value is combined with other outflow types, which can sometimes make it unclear how much water has actually entered the system versus how much has infiltrated.

To separate infiltration losses:

* Remove negative rainfall or negative SA boundaries if possible.
* The rainfall volume can be calculated manually based on the rainfall rate and the rainfall area, or by running the model without soil infiltration to obtain the "S/RF Vol In" value in the absence of any soil infiltration.
* Run the model with soil infiltration. The difference in "S/RF Vol In" value is the volume of water infiltrated by soil layer.
* If "S/RF Vol Out" value are reported, the total of "S/RF Vol Out" and the "S/RF Vol In" difference is the volume of water infiltrated by soil layer.

Adding 2D PO lines across boundaries or 2D PO GWVol polygon can also help track how much water leaves the system via different pathways. TUFLOW does not currently provide a simple breakdown of water volumes, but understanding how mass balance values are calculated can help extract the needed information.

== Why is water not leaving the system post-peak in a groundwater model? ==
If water remains in the system after the peak flow, review the following parameters:

Groundwater related:
* Check groundwater depth output (GWd) to see if the soil layer became saturated. Increasing soil layer thickness can increase the storage and sustain infiltration loss.
* Horizontal hydraulic conductivity: Low values may restrict lateral groundwater movement, limiting drainage, and keeping the soil layer full.
* However, if the horizontal hydraulic conductivity is high, the soil layer may generate continuous baseflow after the rainfall event, which can sustain higher water levels in creeks.
Surface water related:
* Downstream boundary conditions: An HT boundary may hinder efficient water exit. Consider testing with a QH boundary.

Running sensitivity tests by adjusting horizontal conductivity, initial moisture, and soil thickness can help identify key factors affecting outflow rates.

== Why does groundwater exfiltrate immediately after the simulation starts? ==
If the initial soil moisture is saturated or near saturation, groundwater can immediately discharge to surface at low lying areas, causing rapid surface expression even before rainfall. This type of model setup is sometimes applied if the initial groundwater condition is unknown. It is suggested to try the following to reduce the impact of the initial condition:

* If initial groundwater condition is known (e.g. groundwater level monitoring data, soil moisture focusing data), set the initial condition using <tt>Set/Read GRID/Read GIS IGW Depth/Elevation</tt> commands.
* If initial groundwater condition is unknown, conduct a warm-up run to drain groundwater to a certain level before applying rainfall.
* Conduct sensitivity tests by adjusting initial groundwater depth/level and horizontal hydraulic conductivity.
* Find observation data (e.g. surface water flux, water level) to calibrate the initial groundwater condition and the model parameters.

== How can interflow behaviour be better aligned with observed conditions? ==

* Ensuring groundwater inputs and outputs are balanced is key.
* Comparing groundwater accumulation areas with surface water flooding can help verify results.
* Using the groundwater XDMF output can assist in visualising flow behaviour and refining parameter selection.

Fine-tuning soil properties, hydraulic conductivity, and boundary conditions will improve interflow simulation accuracy.

== Why does the groundwater lateral flux calculation include porosity? ==
Benchmarking tests have identified that the current sub surface flow equation in TUFLOW underestimates steady state discharge rates due to the inclusion of porosity. While the steady state water level gradient is correct, transient state simulations show discrepancies.

To address this, <tt>Groundwater Horizontal Flux Include Porosity</tt> command can be used to turn the porosity term on or off in the equation.

*OFF for correct modelling.

*ON for backward compatibility with previous versions.

== Why is hydraulic conductivity measured in mm/hr instead of m/d? ==
TUFLOW currently uses mm/hr for hydraulic conductivity to align with the ILCL units and Green Ampt infiltration rate, which is commonly used in surface water modelling. Please convert the value if the reference uses different unit of hydraulic conductivity.

== Why is the groundwater model affecting areas beyond the expected flow path? ==
Groundwater movement in TUFLOW is influenced by topography, soil properties, and groundwater parameters. If groundwater is introduced, infiltrated water may reappear on the surface depending on these factors.

Key considerations:

* Without horizontal groundwater movement, infiltrated water is lost from the system. When groundwater movement is enabled, water can accumulate in low-lying areas or flow towards the downstream boundary.
* Unexpected groundwater presence in areas without assigned soil depths may be due to groundwater behaviour at boundaries or model-wide settings.
* The 2d_po regional outputs introduced in version AF can assist with analysing groundwater movement and verifying model behaviour.

== Should soil layers be assigned across the entire model? ==
If groundwater is being simulated, defining soil layers across the full model domain can provide more control over groundwater behaviour.

Options include:

* Assigning a depth of zero in areas where groundwater should not be present.
* Setting a large depth in areas where groundwater storage is needed but horizontal transmission is not desired.

Model validation using observed data is recommended to confirm that groundwater interactions align with real-world conditions.

== How can a lined filtration trench be modelled? ==
A lined filtration trench can be represented using one of the following methods:

'''1D Channel Approach'''

* Model the trench as a 1d_nwk “Q” type structure, which uses a depth-discharge relationship.
* Connect the trench to multiple 2D cells using a 2d_bc SX line.
* If the trench is long, divide it into multiple sections to improve accuracy.

'''1D Pit and Culvert Approach'''

* Use multiple 1d_nwk Q pits connected via a 1d_nwk culvert.
* The connected 2D cells are automatically selected using the sag or on-grade method (see section 5.12.3.3 of the TUFLOW manual).
* To manually control cell connections, set the 1d_nwk Conn_No attribute to a negative value. For example, Conn_No = -1 ensures each pit connects to only one 2D cell.
* This method allows the trench to be represented as multiple pit points, each selecting one 2D cell and linking to the 1D node using X connectors.

'''Additional Considerations'''

* Pit Inlet Discharge Curve: If using a 1D network, pre-compute the discharge for various depths to define a suitable pit inlet discharge curve.
* Interflow Functionality: The use of interflow depends on the cell size relative to the trench feature.
* Two-Stage Modelling Approach: One method involves running a 2D infiltration simulation first to determine infiltration rates. The infiltration can then be applied as a 1D boundary condition in a second simulation to represent flow into the drainage system.

TUFLOW is currently developing functionality to dynamically link interflow to a 1D network, which will allow infiltrated subsurface flows to connect directly to 1D nodes or pipes in future releases.

== What methods and result outputs can be used to quantify infiltration losses over a given area? ==
To assess infiltration losses, the following outputs can be used:

'''Map Output Data Types'''

* CI (Cumulative Infiltration): Displays the total infiltration over time.

* IR (Infiltration Rate): Shows the infiltration rate at each timestep.

* In TUFLOW 2025.2.0 version and later, QZ (average vertical flux over the past output interval) and QZI (cumulative vertical flux) can be applied.

'''Point Output (2d_po) Approach'''

* If infiltration data is needed for a specific area, a 2d_po region can be set up.

Both methods help understand how infiltration occurs across different areas.

== Why does changing the initial soil moisture in the Green-Ampt (GA) infiltration method not affect infiltration rates as expected? ==
In the 2023 release of TUFLOW, the treatment of initial soil moisture in the GA method was updated to accommodate horizontal soil water movement. This change allows soil moisture to flow between sub-surface cells and be removed via evapotranspiration, making it more dynamic over time. Instead of remaining static in the infiltration equation, the initial soil moisture is now used as the cumulative infiltration (F) at the first timestep of the simulation. This means:

* The infiltration rate at the start of the simulation is influenced by the initial soil moisture, but subsequent infiltration behaviour depends on the balance of infiltration, drainage, and evapotranspiration.

* If no soil thickness is defined, the model assumes dZ = 0, meaning the initial moisture value is ignored altogether.

'''Suggested Workarounds'''

:'''1. Reverting to the pre-2023 method.'''

::Use the backward compatibility switch:

::Defaults == Pre 2023

::Note: This changes multiple default settings, not just the GA method.

:'''2. Adjusting the soil porosity in the .tsoil file.'''

::Instead of defining initial soil moisture separately set: Adjusted Porosity = Porosity - Initial Moisture

::Example: If soil porosity is 0.385 and initial soil moisture is 0.200, set the porosity to 0.185.

TUFLOW is updating documentation to clarify this change and is developing a dedicated command to revert to the original GA method without affecting other default settings. Further refinements are also being considered for long-term simulations involving multiple wet/dry cycles.

Feedback or specific examples can be provided to TUFLOW Support via support@tuflow.com.

== Can groundwater be trapped beneath impervious areas to prevent unrealistic exfiltration? ==
Currently, TUFLOW does not directly put a 'lid' on soil surface, even if the surface imperviousness is set to 1.0. The existing groundwater model calculates exfiltration (upward flux) based on mass balance only, meaning that groundwater can still migrate upward even in areas where the surface is defined as impervious.

Recognising the importance of this feature for improving groundwater representation in urban modelling, consideration is being given to incorporating a method to account for trapped groundwater as part of future TUFLOW release.

In the meantime, the issue may be mitigated by:

* Remove the soil layer under the impervious surface.
* Adjusting the soil thickness and properties to reduce unrealistic seepage effects, e.g. set horizontal hydraulic conductivity to zero for soil polygons beneath impervious areas. Note this stops groundwater from flowing to this area through lateral flux. However, water can still surge from the soil layer beneath, and then to the surface if multiple soil layers are used.

If this issue is recurring or if there are specific use cases where this feature would be beneficial, feedback is encouraged via support@tuflow.com.

== What is the recommended method for representing a railway ballast area? ==

Traditionally, a railway ballast is modelled using layered flow constriction with high blockage and form loss value.

With the groundwater feature, it can also be represented as a soil layer (specific Soil ID) with high infiltration, suitable porosity, and high hydraulic conductivity in both horizontal and vertical directions. If the railway ballast area is the only area in the model that a soil layer is applied, the soil layers do not need to be applied across the entire model.

== Why does setting up a second soil layer for a model require using the ‘CO’ type? ==
When defining Soil Layer 2, the convective (CO) layer type must be used. This soil type requires fewer inputs compared to other soil types that require parameters used to calculate surface infiltration. If another type is assigned, TUFLOW returns ERROR 2314 (invalid Soil ID).

To set up CO soil type:

* Define a new Soil ID for Layer 2 using the CO type in tsoil file.
* Use <tt>Set/Read GRID/Read GIS Soil Layer X</tt> commands to update soil layer under the 1st layer the new CO type.

 

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Groundwater Modelling Advice

2025-12-03T10:05:57Z

Tuflowduncan: /* How should peat soils be represented in a direct rainfall model? */

= Introduction =
From the 2023-03 release and onwards, horizontal flow (advection) of water and multiple vertical groundwater layers when using TUFLOW HPC are supported. This page provides useful groundwater modelling advice to users.

= Groundwater Linking to 1D (ESTRY or SWMM) =
Since the 2025.2.0 release, TUFLOW supports connecting the 1D domain (either ESTRY or SWMM) to 2D groundwater layers. This enables users to model features such as detention basins with subsurface drainage or other green infrastructure directly within a TUFLOW model and represent groundwater and surface water impacts. The physical infrastructure collecting the groundwater varies, but is typically a perforated or slotted pipe in loose fill such as gravel or sand.

The discharge through the connection is typically modeled using a depth vs discharge curve where the depth applied is the pressure in the groundwater at the location of the connection. This relationship is often defined using the orifice equation where the orifice coefficient depends on the configuration. This section below contains guidance for generating a curve based on the orifice equation.

== Depth vs Discharge Curves ==
This section provides two methods for generating depth vs discharge curves based on the orifice equation: 

[[File: orifice_equation.png]] 
Where:
*'''''CdA''''' is the orifice coefficient
:*'''''Cd''''' is the discharge coefficient
:*'''''A''''' is the cross-sectional area of the orifice
*'''''Hup''''' is the upstream water level
*'''''Hdown''''' is the higher of the downstream obvert or downstream water level 

The following link provides some guidance on how to select the orifice coefficient: https://wiki.sustainabletechnologies.ca/wiki/Flow_through_perforated_pipe

=== Python ===
The following python code can be used to generate depth vs discharge curves, which can then be input into a model with groundwater linking to 1D.

'''import''' math 
'''import''' numpy '''as''' np 
gravity_metric = '''9.81 '''# Metric Units: m/s^2
gravity_us_customary = '''32.2 '''# US Customary Units: ft/s^2 
'''def''' generate_orifice_depth_vs_discharge(us_units, orifice_coefficient, depth_max, depth_step, output_filename):
 gravity = gravity_us_customary '''if''' us_units '''else''' gravity_metric 
 depths = np.arange('''0.0''', depth_max, depth_step)
 vec_func = np.vectorize('''lambda''', e: orifice_coefficient * math.sqrt('''2''' * gravity * e))
 discharges = vec_func(depths) 
 values = np.column_stack((depths, discharges)) 
 np.savetxt(output_filename, values, delimiter=",", fmt="%.7g", header='Depth, Discharge', comments=<nowiki>''</nowiki>) 
'''if''' __name__ == "__main__":
 use_us_units = False
 orifice_coefficent_value = 0.002 # Orifice coefficient
 depth_max_value = 2.0 # Maximum depth (in meters or feet)
 depth_step_value = 0.02 # Value to increment by (in meters or feet) 
 out_filename = "orifice_depth_vs_discharge.csv" 
 generate_orifice_depth_vs_discharge(use_us_units, orifice_coefficent_value, depth_max_value, depth_step_value, out_filename)

=== Excel ===
The following excel file can be used to generate depth vs discharge curves, which can then be input into a model with groundwater linking to 1D. The file contains a two examples, one for Metric and one for US Customary.

[https://downloads.tuflow.com/Private_Download/depth_vs_discharge.xlsx Depth vs Discharge - Excel]

= Common Questions Answered (FAQ) =

== What are the benefits of integrating groundwater modelling into flood simulations? ==
The addition of a groundwater model accounts for the attenuation of the rainfall-runoff response and the discharge of soil water to creeks. This helps in long-term simulations by generating base flow to the surface runoff, and helps predict the infiltration capacity for subsequent rainfall events by tracking the long term change in soil moisture. For examples of real world applications, please see:
* Australian Water School Webinar on [https://www.tuflow.com/library/webinars/#dec2024_groundwater_modelling TUFLOW Groundwater Flow Modelling and its Application]
* 2024 Enhancing Catchment Runoff Simulations Using Soil Moisture Dependent Hydraulic Conductivity, Gao et al, HWRS. [https://www.tuflow.com/media/8855/2024-enhancing-catchment-runoff-simulations-using-soil-moisture-dependent-hydraulic-conductivity-gao-et-al-errata.pdf link]
* 2023 Continuous Direct Rainfall Hydraulic Modelling with Coupled Surface Ground Water Interaction, Gao et al, HWRS. [https://www.tuflow.com/media/8523/2023-continuous-direct-rainfall-hydraulic-modelling-with-coupled-surface-ground-water-interaction-gao-et-al-hwrs.pdf link]

== How can a gravel trench be represented if it does not allow infiltration but connects two attenuation basins and intercepts runoff? ==
If the gravel trench does not allow infiltration but acts as a conveyance feature, it can be represented as a 1D channel or pipe to connect the two attenuation basins.

The groundwater functionality can be used by setting the surface infiltration rate as zero to model the lateral movement through the trench only. 2D cells with non-zero infiltration rate are still needed to infiltrate the surface water to the soil layer. However, soil water can discharge to the surface if the soil layer becomes full at the zero infiltration cells (TUFLOW does not put a 'lid' on soil surface). This approach is not recommended if the gravel trench is expected to become full.

== How should the Initial Loss/Continuing Loss (ILCL) infiltration method be applied, and are there standard values for different land cover types? ==
To use ILCL infiltration, the Soil ID must be defined in the model, either globally or spatially using a 2d_soil layer, which is read into the tgc file with the <tt>Read GIS Soil</tt> command. The 2d_grd check file can be used to confirm that the correct Soil IDs have been applied across the model.

TUFLOW does not provide standard IL/CL values, but values may be estimated from databases such as the CSIRO Soil Atlas. ARR Book 9, Section 6.4.2 offers general guidance for rainfall loss values, but this is separate from ILCL soil infiltration.

== Can water exfiltrate from subsurface layers other than the top layer? ==
Water can move both horizontally within a soil layer and vertically between layers. Downward flow is controlled by convective hydraulic conductivity (CO), while upward flow occurs through surcharging.

== How can permeable pavements be modelled? ==
Permeable pavements can be represented using soil layers. The simplest approach is to define infiltration using a 2d_soil layer, assigning a Soil ID with infiltration properties matching permeable pavements. This method removes infiltrated water from the model. If groundwater movement is important, multiple soil layers can be used to model horizontal flow and subsurface drainage.

== How should peat soils be represented in a direct rainfall model? ==
If observed flow data is available, calibrating the model to these measurements would be the best approach. If not, using a lumped hydrology model as a comparison for flow estimates is recommended. Since peat is often saturated, infiltration rates may be low, but lateral water movement could still occur. In this case, using the interflow functionality in TUFLOW may help better represent water movement within the catchment.

== How can a French drain (filter drain) be represented? ==
There is no direct method for modelling a French drain in TUFLOW, but there are a few possible approaches.

* One option is to drain water directly from surface cells using 1D pit.
* In TUFLOW 2025.2.0 version and later, 2D groundwater layers can also be connected to the 1D domain using SX BC.
In the 2 methods above, it's required to use Darcy’s law to estimate discharge rates and create a depth vs discharge curves.
* Alternatively, the model cell size can be reduced to the trench width to conduct localised modelling of the subsurface flow through the drain. The modelling result can be used to estimate infiltration rates to connect 1D and 2D (surface or subsurface) in a model with larger cell size and larger extent.

== How do soil parameters like thickness and hydraulic conductivity impact groundwater modelling? ==
Soil thickness and hydraulic conductivity control how water moves through the ground in TUFLOW’s groundwater modelling.

In general, a thicker soil layer increases soil capacity and has a greater ability to attenuate surface runoff during floods. A thicker soil layer also contributes to the continuous release of baseflow when it isn’t raining.

Hydraulic conductivity controls how easily water flows due to the gravity drain. During a flood event, vertical hydraulic conductivity determines the rate of infiltration from soil surface or from the soil layer above. Horizontal hydraulic conductivity affects the lateral movement of groundwater towards the bottom of the hillslope. A higher horizontal hydraulic conductivity increases the groundwater discharge to creek and produces more baseflow, which also frees up the soil capacity faster for the next rainfall event.

These factors are investigated in detail by this HWRS paper [https://www.tuflow.com/media/8523/2023-continuous-direct-rainfall-hydraulic-modelling-with-coupled-surface-ground-water-interaction-gao-et-al-hwrs.pdf Gao et al. 2023]

== How is total volume in and infiltration loss reported, and how can they be separated? ==
TUFLOW reports total volume in using multiple components, including rainfall, inflows, and other sources. The infiltration losses are reported in the HPC mass balance CSV file (MB_HPC.csv). However, it is subtracted from the "S/RF Vol In" value if the rainfall rate is larger than the infiltration rate, and is reported as "S/RF Vol Out" value if the infiltration rate is higher than rainfall rate. In addition, this value is combined with other outflow types, which can sometimes make it unclear how much water has actually entered the system versus how much has infiltrated.

To separate infiltration losses:

* Remove negative rainfall or negative SA boundaries if possible.
* The rainfall volume can be calculated manually based on the rainfall rate and the rainfall area, or by running the model without soil infiltration to obtain the "S/RF Vol In" value in the absence of any soil infiltration.
* Run the model with soil infiltration. The difference in "S/RF Vol In" value is the volume of water infiltrated by soil layer.
* If "S/RF Vol Out" value are reported, the total of "S/RF Vol Out" and the "S/RF Vol In" difference is the volume of water infiltrated by soil layer.

Adding 2D PO lines across boundaries or 2D PO GWVol polygon can also help track how much water leaves the system via different pathways. TUFLOW does not currently provide a simple breakdown of water volumes, but understanding how mass balance values are calculated can help extract the needed information.

== Why is water not leaving the system post-peak in a groundwater model? ==
If water remains in the system after the peak flow, review the following parameters:

Groundwater related:
* Check groundwater depth output (GWd) to see if the soil layer became saturated. Increasing soil layer thickness can increase the storage and sustain infiltration loss.
* Horizontal hydraulic conductivity: Low values may restrict lateral groundwater movement, limiting drainage, and keeping the soil layer full.
* However, if the horizontal hydraulic conductivity is high, the soil layer may generate continuous baseflow after the rainfall event, which can sustain higher water levels in creeks.
Surface water related:
* Downstream boundary conditions: An HT boundary may hinder efficient water exit. Consider testing with a QH boundary.

Running sensitivity tests by adjusting horizontal conductivity, initial moisture, and soil thickness can help identify key factors affecting outflow rates.

== Why does groundwater exfiltrate immediately after the simulation starts? ==
If the initial soil moisture is saturated or near saturation, groundwater can immediately discharge to surface at low lying areas, causing rapid surface expression even before rainfall. This type of model setup is sometimes applied if the initial groundwater condition is unknown. It is suggested to try the following to reduce the impact of the initial condition:

* If initial groundwater condition is known (e.g. groundwater level monitoring data, soil moisture focusing data), set the initial condition using <tt>Set/Read GRID/Read GIS IGW Depth/Elevation</tt> commands.
* If initial groundwater condition is unknown, conduct a warm-up run to drain groundwater to a certain level before applying rainfall.
* Conduct sensitivity tests by adjusting initial groundwater depth/level and horizontal hydraulic conductivity.
* Find observation data (e.g. surface water flux, water level) to calibrate the initial groundwater condition and the model parameters.

== How can interflow behaviour be better aligned with observed conditions? ==

* Ensuring groundwater inputs and outputs are balanced is key.
* Comparing groundwater accumulation areas with surface water flooding can help verify results.
* Using the groundwater XDMF output can assist in visualising flow behaviour and refining parameter selection.

Fine-tuning soil properties, hydraulic conductivity, and boundary conditions will improve interflow simulation accuracy.

== Why does the groundwater lateral flux calculation include porosity? ==
Benchmarking tests have identified that the current sub surface flow equation in TUFLOW underestimates steady state discharge rates due to the inclusion of porosity. While the steady state water level gradient is correct, transient state simulations show discrepancies.

To address this, <tt>Groundwater Horizontal Flux Include Porosity</tt> command can be used to turn the porosity term on or off in the equation.

*OFF for correct modelling.

*ON for backward compatibility with previous versions.

== Why is hydraulic conductivity measured in mm/hr instead of m/d? ==
TUFLOW currently uses mm/hr for hydraulic conductivity to align with the ILCL units and Green Ampt infiltration rate, which is commonly used in surface water modelling. Please convert the value if the reference uses different unit of hydraulic conductivity.

== Why is the groundwater model affecting areas beyond the expected flow path? ==
Groundwater movement in TUFLOW is influenced by topography, soil properties, and groundwater parameters. If groundwater is introduced, infiltrated water may reappear on the surface depending on these factors.

Key considerations:

* Without horizontal groundwater movement, infiltrated water is lost from the system. When groundwater movement is enabled, water can accumulate in low-lying areas or flow towards the downstream boundary.
* Unexpected groundwater presence in areas without assigned soil depths may be due to groundwater behaviour at boundaries or model-wide settings.
* The 2d_po regional outputs introduced in version AF can assist with analysing groundwater movement and verifying model behaviour.

== Should soil layers be assigned across the entire model? ==
If groundwater is being simulated, defining soil layers across the full model domain can provide more control over groundwater behaviour.

Options include:

* Assigning a depth of zero in areas where groundwater should not be present.
* Setting a large depth in areas where groundwater storage is needed but horizontal transmission is not desired.

Model validation using observed data is recommended to confirm that groundwater interactions align with real-world conditions.

== How can a lined filtration trench be modelled? ==
A lined filtration trench can be represented using one of the following methods:

'''1D Channel Approach'''

* Model the trench as a 1d_nwk “Q” type structure, which uses a depth-discharge relationship.
* Connect the trench to multiple 2D cells using a 2d_bc SX line.
* If the trench is long, divide it into multiple sections to improve accuracy.

'''1D Pit and Culvert Approach'''

* Use multiple 1d_nwk Q pits connected via a 1d_nwk culvert.
* The connected 2D cells are automatically selected using the sag or on-grade method (see section 5.12.3.3 of the TUFLOW manual).
* To manually control cell connections, set the 1d_nwk Conn_No attribute to a negative value. For example, Conn_No = -1 ensures each pit connects to only one 2D cell.
* This method allows the trench to be represented as multiple pit points, each selecting one 2D cell and linking to the 1D node using X connectors.

'''Additional Considerations'''

* Pit Inlet Discharge Curve: If using a 1D network, pre-compute the discharge for various depths to define a suitable pit inlet discharge curve.
* Interflow Functionality: The use of interflow depends on the cell size relative to the trench feature.
* Two-Stage Modelling Approach: One method involves running a 2D infiltration simulation first to determine infiltration rates. The infiltration can then be applied as a 1D boundary condition in a second simulation to represent flow into the drainage system.

TUFLOW is currently developing functionality to dynamically link interflow to a 1D network, which will allow infiltrated subsurface flows to connect directly to 1D nodes or pipes in future releases.

== What methods and result outputs can be used to quantify infiltration losses over a given area? ==
To assess infiltration losses, the following outputs can be used:

'''Map Output Data Types'''

* CI (Cumulative Infiltration): Displays the total infiltration over time.

* IR (Infiltration Rate): Shows the infiltration rate at each timestep.

* In TUFLOW 2025.2.0 version and later, QZ (average vertical flux over the past output interval) and QZI (cumulative vertical flux) can be applied.

'''Point Output (2d_po) Approach'''

* If infiltration data is needed for a specific area, a 2d_po region can be set up.

Both methods help understand how infiltration occurs across different areas.

== Why does changing the initial soil moisture in the Green-Ampt (GA) infiltration method not affect infiltration rates as expected? ==
In the 2023 release of TUFLOW, the treatment of initial soil moisture in the GA method was updated to accommodate horizontal soil water movement. This change allows soil moisture to flow between sub-surface cells and be removed via evapotranspiration, making it more dynamic over time. Instead of remaining static in the infiltration equation, the initial soil moisture is now used as the cumulative infiltration (F) at the first timestep of the simulation. This means:

* The infiltration rate at the start of the simulation is influenced by the initial soil moisture, but subsequent infiltration behaviour depends on the balance of infiltration, drainage, and evapotranspiration.

* If no soil thickness is defined, the model assumes dZ = 0, meaning the initial moisture value is ignored altogether.

'''Suggested Workarounds'''

:'''1. Reverting to the pre-2023 method.'''

::Use the backward compatibility switch:

::Defaults == Pre 2023

::Note: This changes multiple default settings, not just the GA method.

:'''2. Adjusting the soil porosity in the .tsoil file.'''

::Instead of defining initial soil moisture separately set: Adjusted Porosity = Porosity - Initial Moisture

::Example: If soil porosity is 0.385 and initial soil moisture is 0.200, set the porosity to 0.185.

TUFLOW is updating documentation to clarify this change and is developing a dedicated command to revert to the original GA method without affecting other default settings. Further refinements are also being considered for long-term simulations involving multiple wet/dry cycles.

Feedback or specific examples can be provided to TUFLOW Support via support@tuflow.com.

== Can groundwater be trapped beneath impervious areas to prevent unrealistic exfiltration? ==
Currently, TUFLOW does not directly put a 'lid' on soil surface, even if the surface imperviousness is set to 1.0. The existing groundwater model calculates exfiltration (upward flux) based on mass balance only, meaning that groundwater can still migrate upward even in areas where the surface is defined as impervious.

Recognising the importance of this feature for improving groundwater representation in urban modelling, consideration is being given to incorporating a method to account for trapped groundwater as part of future TUFLOW release.

In the meantime, the issue may be mitigated by:

* Remove the soil layer under the impervious surface.
* Adjusting the soil thickness and properties to reduce unrealistic seepage effects, e.g. set horizontal hydraulic conductivity to zero for soil polygons beneath impervious areas. Note this stops groundwater from flowing to this area through lateral flux. However, water can still surge from the soil layer beneath, and then to the surface if multiple soil layers are used.

If this issue is recurring or if there are specific use cases where this feature would be beneficial, feedback is encouraged via support@tuflow.com.

== What is the recommended method for representing a railway ballast area? ==

Traditionally, a railway ballast is modelled using layered flow constriction with high blockage and form loss value.

With the groundwater feature, it can also be represented as a soil layer (specific Soil ID) with high infiltration, suitable porosity, and high hydraulic conductivity in both horizontal and vertical directions. If the railway ballast area is the only area in the model that a soil layer is applied, the soil layers do not need to be applied across the entire model.

== Why does setting up a second soil layer for a model require using the ‘CO’ type? ==
When defining Soil Layer 2, the convective (CO) layer type must be used. This soil type requires fewer inputs compared to other soil types that require parameters used to calculate surface infiltration. If another type is assigned, TUFLOW returns ERROR 2314 (invalid Soil ID).

To set up CO soil type:

* Define a new Soil ID for Layer 2 using the CO type in tsoil file.
* Use <tt>Set/Read GRID/Read GIS Soil Layer X</tt> commands to update soil layer under the 1st layer the new CO type.

 

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FM Tutorial M02 QGIS GPKG Flood Modeller1D/ESTRY 1D Link

2025-09-26T14:54:48Z

Tuflowduncan: /* Method */

=Introduction=

This page describes the method in QGIS for linking TUFLOW 1D ESTRY networks to a 1D river channel represented within Flood Modeller. Firstly, a pipe network represented in ESTRY will be linked to Flood Modeller using an "X1DH" link. The Flood Modeller 1D network will then be extended downstream by connecting it to an ESTRY river network using an "X1DQ" link.

=Method=
<ol>
<li> Open the layers '''1d_x1d_FMT_M01_nwk_001_P''', '''1d_x1d_FMT_M01_nodes_001_P''', and '''1d_nwk_FMT_M02_Pipes_001_L''' from the '''FMT_M01_002.gpkg''' into QGIS.
<li>Observe that Pipe16 and Pipe18 in the layer '''1d_nwk_FMT_M02_Pipes_001_L''' representing the pipe network have been snapped to node “FC01.11” of the layer '''1d_x1d_FMT_M01_nodes_002_P'''. As an additional node hasn’t been manually added the Flood Modeller-ESTRY link at this location is assumed to be an “X1DH” link. If you open the attribute table you will be able to see that the Conn_1D_2D attribute for “Pipe16” and “Pipe18” has been left blank as an “X1DH” link is used by default and therefore doesn’t need to be specified.
<li>Open the Flood Modeller network (.DAT) file '''FMT_M01_002.dat''' in the Flood Modeller Pro interface. Observe that the updated network file terminates at a stage-time boundary unit named “DSBDY”. This does not need to contain any time-varying data as this data will be overridden by the water levels provided by ESTRY.
<li>Open the layers'''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' within QGIS. These layers are located within the '''Module_data\Module_02\Creek ''' folder.
<li>Drag and drop the GIS layers '''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the three GIS layers in the Layers Panel and reload them from the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>The GIS layer '''1d_nwk_FMT_M02_channels_001_L''' represents the open channel ESTRY network downstream of the Flood Modeller network. A stage-time boundary named "DS_BC" has been set up at the downstream end of the ESTRY network in layer '''1d_bc_FMT_m02_001_P'''.
<li>Observe that an additional node "DSBDY" is present within the updated Read GIS ISIS Nodes layer '''1d_x1d_FMT_M01_nodes_002_P''' at the downstream end of the Flood Modeller network.

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part1.mp4 |width=1123}} 

<li>Open the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS. It is located within the '''Module_data\Module_02\Creek''' folder.
<li>Drag and drop the layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel. Close the layer in the Layers Panel.
<li>Reload the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS from the project GeoPackage file. Turn on Toggle Editing mode and open Field Calculator. Select the field "Source" from the "Update Existing Field" dropdown and enter the expression <nowiki/>'..\\xs\\' ||source to prepend "..\\xs\\" to all rows for this field. The results will be the Source will be set up as per the below image which will ensure that the locations of the csv files are correctly referenced.
 [[File:Source.png|frameless|300x300px]] 
<li>Create a new folder entitled '''xs''' in the '''TUFLOW\model''' folder. Copy the csv files listed below from the '''Module_data\Module_02\Creek''' folder into the newly created '''TUFLOW\model\xs''' folder. These csv files will be used to define the geometry of the river channel cross sections.
*ds_weir.csv
*ds1.csv
*ds2.csv
*ds3.csv
*ds4.csv
*ds5.csv
*ds5_weir.csv
<li>Copy the csv file '''Weir_HT.csv''' from the '''Module_data\Module_02\Creek''' folder to the '''TUFLOW\bc_dbase''' folder. This csv file contains the stage time data that will be applied at the downstream boundary node 'DS_BC'. A constant stage value of 35.5m AOD has been applied .
<li>An additional row needs to be added to '''bc_dbase_FMT_M02.csv''' to apply the stage-time values from '''Weir_HT.csv'''. The revised bc_dbase should look like the figure below:

 
[[File:Bc dbase FMT M01 update.jpg||1200px]] 
 

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part2.mp4 |width=1123}} 

<li>As there is gap between the final node of the Flood Modeller network and the start of the ESTRY network a connector "X" type channel type has been added to connect them. This is present within the '''1d_nwk_FMT_M02_channels_001_L layer.''' This must be digitised from the ESTRY channel (from the first vertex on the polyline) to the Flood Modeller node.
<li>To complete the "X1DQ" link a manually created ESTRY node must be snapped to the Flood Modeller node and have a "Conn_1D_2D" attribute of "X1DQ" specified. To do this, import an empty 1d_nwke_empty_P.gpkg from within the '''FMT_tutorial\FMT_M02\TUFLOW\model\gis\empty''' folder.
<li>Save the empty layer as '''1d_nwke_X1DQ_P''' in the '''TUFLOW\model\gis folder'''. Drag and drop this layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the layer '''1d_nwke_X1DQ_P''' within QGIS and then reload it from the the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>Turn on Toggle Editing for the layer '''1d_nwke_X1DQ_P''' and add the attribute values shown in the table below. Save the layer.
{| class="wikitable" align="center" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;" | Attribute
! style="background-color:#005581; font-weight:bold; color:white;" | Value
|-
| ID || ds2 (remember that Flood Modeller is case sensitive)
|-
| Type || Node
|-
| Conn_1D_2D || X1DQ
|}

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part3.mp4 |width=1123}} 

=Conclusion=

The ESTRY pipe network for the proposed development has been connected via an "X1DH" link to discharge via two pipes into the Flood Modeller network by snapping together the nodes in a 1d_nwk_L layer to a node in the 1d_x1d_P layer. A 1d_nwk_L layer has been added to represent the open channel network downstream of the Flood Modeller network in ESTRY. The cross section data for this open channel network has been defined by adding a 1d_xs_L layer with links to the source csv files at every cross section location. A connector "X" type channel is present and a 1d_nwke_P layer has been added to connect the ESTRY and Flood Modeller open channel networks via an "X1DQ" link. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Modify Simulation Control Files | Flood Modeller Tutorial 2]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

</ol>

FM Tutorial M02 QGIS SHP Flood Modeller1D/ESTRY 1D Link

2025-09-26T14:52:05Z

Tuflowduncan: /* Conclusion */

=Introduction=

This page describes the method in QGIS for linking TUFLOW 1D ESTRY networks to a 1D river channel represented within Flood Modeller. Firstly, a pipe network represented in ESTRY will be linked to Flood Modeller using an X1DH link. The Flood Modeller 1D network will then be extended downstream by connecting it to an ESTRY river network using an "X1DQ" link.

=Method=
<ol>
<li> Open the layers '''1d_x1d_FMT_M01_nwk_001_P.shp''', '''1d_x1d_FMT_M01_nodes_001_P''', and '''1d_nwk_FMT_M02_Pipes_001_L.shp''' in QGIS.
<li>Observe that Pipe16 and Pipe18 in the layer '''1d_nwk_FMT_M02_Pipes_001_L.shp''' representing the pipe network have been snapped to node “FC01.11” of the layer '''1d_x1d_FMT_M01_nodes_002_P.shp'''. As an additional node hasn’t been manually added the Flood Modeller-ESTRY link at this location is assumed to be an “X1DH” link. If you open the attribute table you will be able to see that the Conn_1D_2D attribute for “Pipe16” and “Pipe18” has been left blank as an “X1DH” link is used by default and therefore doesn’t need to be specified.
<li>Open the Flood Modeller network (.DAT) file '''FMT_M01_002.dat''' in the Flood Modeller Pro interface. Observe that the updated network file terminates at a stage-time boundary unit named “DSBDY”. This does not need to contain any time-varying data as this data will be overridden by the water levels provided by ESTRY.
<li>Copy the GIS layers '''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' within '''Module_data\Module_02\Creek ''' into the '''TUFLOW\model\gis''' folder.
<li>The GIS layer '''1d_nwk_FMT_M02_channels_001_L.shp''' represents the open channel ESTRY network downstream of the Flood Modeller network. A stage-time boundary named "DS_BC" has been set up at the downstream end of the ESTRY network in layer '''1d_bc_FMT_m02_001_P.shp'''.
<li>Observe that an additional node "DSBDY" is present within the updated Read GIS ISIS Nodes layer '''1d_x1d_FMT_M01_nodes_002_P.shp''' at the downstream end of the Flood Modeller network.

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS SHP Part1.mp4 |width=1123}} 

<li>Create a new folder entitled '''xs''' in the '''TUFLOW\model''' folder. Copy the layer '''1d_xs_FMT_M02_creek_001_L.shp''' and the csv files listed below from the '''Module_data\Module_02\Creek''' folder into the newly created '''TUFLOW\model\xs''' folder. These csv files in combination with the layer '''1d_xs_FMT_M02_creek_001_L.shp''' will be used to define the geometry and locations of the river channel cross sections.
*ds_weir.csv
*ds1.csv
*ds2.csv
*ds3.csv
*ds4.csv
*ds5.csv
*ds5_weir.csv
<li>Copy the csv file '''Weir_HT.csv''' from the '''Module_data\Module_02\Creek''' folder to the '''TUFLOW\bc_dbase''' folder. This csv file contains the stage time data that will be applied at the downstream boundary node 'DS_BC'. A constant stage value of 35.5m AOD has been applied .
<li>An additional row needs to be added to '''bc_dbase_FMT_M02.csv''' to apply the stage-time values from '''Weir_HT.csv'''. The revised bc_dbase should look like the figure below:
 
 
[[File:Bc dbase FMT M01 update.jpg||1200px]] 
 

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS SHP Part2.mp4 |width=1123}} 

<li>As there is gap between the final node of the Flood Modeller network and the start of the ESTRY network a connector "X" type channel type has been added to connect them. This is present within the '''1d_nwk_FMT_M02_channels_001_'''L layer. This must be digitised from the ESTRY channel (from the first vertex on the polyline) to the Flood Modeller node.
<li>To complete the "X1DQ" link a manually created ESTRY node must be snapped to the Flood Modeller node and have a "Conn_1D_2D" attribute of "X1DQ" specified. To do this, import an empty 1d_nwke_empty_P.shp layer from within the FMT_tutorial\FMT_M02\TUFLOW\model\gis\empty folder.
<li>Save the empty layer as '''1d_nwke_X1DQ_P.shp''' in the '''TUFLOW\model\gis folder'''.
<li>Turn on Toggle Editing for the layer '''1d_nwke_X1DQ_P.shp''' and add the attribute values shown in the table below.
{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| ID || ds2 (remember that Flood Modeller is case sensitive)
|-
| Type || Node
|-
| Conn_1D_2D || X1DQ
|}

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS SHP Part3.mp4 |width=1123}} 

=Conclusion=

The ESTRY pipe network for the proposed development has been connected via an "X1DH" link to discharge via two pipes into the Flood Modeller network by snapping together the nodes in a 1d_nwk_L layer to a node in the 1d_x1d_P layer. A 1d_nwk_L layer has been added to represent the open channel network downstream of the Flood Modeller network in ESTRY. The cross section data for this open channel network has been defined by adding a 1d_xs_L layer with links to the source csv files at every cross section location. A connector "X" type channel and a 1d_nwke_P layer have been added to connect the ESTRY and Flood Modeller open channel networks via an "X1DQ" link. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Modify Simulation Control Files | Flood Modeller Tutorial 2]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

</ol>

FM Tutorial M02 QGIS SHP Flood Modeller1D/ESTRY 1D Link

2025-09-26T14:51:59Z

Tuflowduncan: /* Method */

=Introduction=

This page describes the method in QGIS for linking TUFLOW 1D ESTRY networks to a 1D river channel represented within Flood Modeller. Firstly, a pipe network represented in ESTRY will be linked to Flood Modeller using an X1DH link. The Flood Modeller 1D network will then be extended downstream by connecting it to an ESTRY river network using an "X1DQ" link.

=Method=
<ol>
<li> Open the layers '''1d_x1d_FMT_M01_nwk_001_P.shp''', '''1d_x1d_FMT_M01_nodes_001_P''', and '''1d_nwk_FMT_M02_Pipes_001_L.shp''' in QGIS.
<li>Observe that Pipe16 and Pipe18 in the layer '''1d_nwk_FMT_M02_Pipes_001_L.shp''' representing the pipe network have been snapped to node “FC01.11” of the layer '''1d_x1d_FMT_M01_nodes_002_P.shp'''. As an additional node hasn’t been manually added the Flood Modeller-ESTRY link at this location is assumed to be an “X1DH” link. If you open the attribute table you will be able to see that the Conn_1D_2D attribute for “Pipe16” and “Pipe18” has been left blank as an “X1DH” link is used by default and therefore doesn’t need to be specified.
<li>Open the Flood Modeller network (.DAT) file '''FMT_M01_002.dat''' in the Flood Modeller Pro interface. Observe that the updated network file terminates at a stage-time boundary unit named “DSBDY”. This does not need to contain any time-varying data as this data will be overridden by the water levels provided by ESTRY.
<li>Copy the GIS layers '''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' within '''Module_data\Module_02\Creek ''' into the '''TUFLOW\model\gis''' folder.
<li>The GIS layer '''1d_nwk_FMT_M02_channels_001_L.shp''' represents the open channel ESTRY network downstream of the Flood Modeller network. A stage-time boundary named "DS_BC" has been set up at the downstream end of the ESTRY network in layer '''1d_bc_FMT_m02_001_P.shp'''.
<li>Observe that an additional node "DSBDY" is present within the updated Read GIS ISIS Nodes layer '''1d_x1d_FMT_M01_nodes_002_P.shp''' at the downstream end of the Flood Modeller network.

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS SHP Part1.mp4 |width=1123}} 

<li>Create a new folder entitled '''xs''' in the '''TUFLOW\model''' folder. Copy the layer '''1d_xs_FMT_M02_creek_001_L.shp''' and the csv files listed below from the '''Module_data\Module_02\Creek''' folder into the newly created '''TUFLOW\model\xs''' folder. These csv files in combination with the layer '''1d_xs_FMT_M02_creek_001_L.shp''' will be used to define the geometry and locations of the river channel cross sections.
*ds_weir.csv
*ds1.csv
*ds2.csv
*ds3.csv
*ds4.csv
*ds5.csv
*ds5_weir.csv
<li>Copy the csv file '''Weir_HT.csv''' from the '''Module_data\Module_02\Creek''' folder to the '''TUFLOW\bc_dbase''' folder. This csv file contains the stage time data that will be applied at the downstream boundary node 'DS_BC'. A constant stage value of 35.5m AOD has been applied .
<li>An additional row needs to be added to '''bc_dbase_FMT_M02.csv''' to apply the stage-time values from '''Weir_HT.csv'''. The revised bc_dbase should look like the figure below:
 
 
[[File:Bc dbase FMT M01 update.jpg||1200px]] 
 

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS SHP Part2.mp4 |width=1123}} 

<li>As there is gap between the final node of the Flood Modeller network and the start of the ESTRY network a connector "X" type channel type has been added to connect them. This is present within the '''1d_nwk_FMT_M02_channels_001_'''L layer. This must be digitised from the ESTRY channel (from the first vertex on the polyline) to the Flood Modeller node.
<li>To complete the "X1DQ" link a manually created ESTRY node must be snapped to the Flood Modeller node and have a "Conn_1D_2D" attribute of "X1DQ" specified. To do this, import an empty 1d_nwke_empty_P.shp layer from within the FMT_tutorial\FMT_M02\TUFLOW\model\gis\empty folder.
<li>Save the empty layer as '''1d_nwke_X1DQ_P.shp''' in the '''TUFLOW\model\gis folder'''.
<li>Turn on Toggle Editing for the layer '''1d_nwke_X1DQ_P.shp''' and add the attribute values shown in the table below.
{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| ID || ds2 (remember that Flood Modeller is case sensitive)
|-
| Type || Node
|-
| Conn_1D_2D || X1DQ
|}

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS SHP Part3.mp4 |width=1123}} 

=Conclusion=

The ESTRY pipe network for the proposed development has been connected via an "X1DH" link to discharge via two pipes into the Flood Modeller network by snapping together the nodes in a 1d_nwk_L layer to a node in the 1d_x1d_P layer. A 1d_nwk_L layer has been added to represent the open channel network downstream of the Flood Modeller network in ESTRY. The cross section data for this open channel network has been defined by adding a 1d_xs_L layer with links to the source csv files at every cross section location. A connector "X" type channel and a 1d_nwke_P layer have been added to connect the ESTRY and Flood Modeller open channel networks via an "X1DQ" link. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Modify Simulation Control Files | Flood Modeller Tutorial 2]].

</ol>

FM Tutorial M02 QGIS SHP Flood Modeller1D/ESTRY 1D Link

2025-09-26T14:48:33Z

Tuflowduncan: /* Method */

=Introduction=

This page describes the method in QGIS for linking TUFLOW 1D ESTRY networks to a 1D river channel represented within Flood Modeller. Firstly, a pipe network represented in ESTRY will be linked to Flood Modeller using an X1DH link. The Flood Modeller 1D network will then be extended downstream by connecting it to an ESTRY river network using an "X1DQ" link.

=Method=
<ol>
<li> Open the layers '''1d_x1d_FMT_M01_nwk_001_P.shp''', '''1d_x1d_FMT_M01_nodes_001_P''', and '''1d_nwk_FMT_M02_Pipes_001_L.shp''' in QGIS.
<li>Observe that Pipe16 and Pipe18 in the layer '''1d_nwk_FMT_M02_Pipes_001_L.shp''' representing the pipe network have been snapped to node “FC01.11” of the layer '''1d_x1d_FMT_M01_nodes_002_P.shp'''. As an additional node hasn’t been manually added the Flood Modeller-ESTRY link at this location is assumed to be an “X1DH” link. If you open the attribute table you will be able to see that the Conn_1D_2D attribute for “Pipe16” and “Pipe18” has been left blank as an “X1DH” link is used by default and therefore doesn’t need to be specified.
<li>Open the Flood Modeller network (.DAT) file '''FMT_M01_002.dat''' in the Flood Modeller Pro interface. Observe that the updated network file terminates at a stage-time boundary unit named “DSBDY”. This does not need to contain any time-varying data as this data will be overridden by the water levels provided by ESTRY.
<li>Copy the GIS layers '''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' within '''Module_data\Module_02\Creek ''' into the '''TUFLOW\model\gis''' folder.
<li>The GIS layer '''1d_nwk_FMT_M02_channels_001_L.shp''' represents the open channel ESTRY network downstream of the Flood Modeller network. A stage-time boundary named "DS_BC" has been set up at the downstream end of the ESTRY network in layer '''1d_bc_FMT_m02_001_P.shp'''.
<li>Observe that an additional node "DSBDY" is present within the updated Read GIS ISIS Nodes layer '''1d_x1d_FMT_M01_nodes_002_P.shp''' at the downstream end of the Flood Modeller network.

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS SHP Part1.mp4 |width=1123}} 

<li>Create a new folder entitled '''xs''' in the '''TUFLOW\model''' folder. Copy the layer '''1d_xs_FMT_M02_creek_001_L.shp''' and the csv files listed below from the '''Module_data\Module_02\Creek''' folder into the newly created '''TUFLOW\model\xs''' folder. These csv files in combination with the layer '''1d_xs_FMT_M02_creek_001_L.shp''' will be used to define the geometry and locations of the river channel cross sections.
*ds_weir.csv
*ds1.csv
*ds2.csv
*ds3.csv
*ds4.csv
*ds5.csv
*ds5_weir.csv
<li>Copy the csv file '''Weir_HT.csv''' from the '''Module_data\Module_02\Creek'''folder to the '''TUFLOW\bc_dbase''' folder. This csv file contains the stage time data that will be applied at the downstream boundary node 'DS_BC'. A constant stage value of 35.5m AOD has been applied .
<li>An additional row needs to be added to '''bc_dbase_FMT_M01.csv''' to apply the stage-time values from '''Weir_HT.csv'''. The revised bc_dbase should look like the figure below:
 
 
[[File:Bc dbase FMT M01 update.jpg||1200px]] 
 

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS SHP Part2.mp4 |width=1123}} 

<li>As there is gap between the final node of the Flood Modeller network and the start of the ESTRY network a connector "X" type channel type has been added to connect them. This must be digitised from the ESTRY channel (from the first vertex on the polyline) to the Flood Modeller node.
<li>To complete the "X1DQ" link a manually created ESTRY node must be snapped to the Flood Modeller node and have a "Conn_1D_2D" attribute of "X1DQ" specified. To do this, import an empty 1d_nwke_empty_P.shp layer from within the FMT_tutorial\FMT_M02\TUFLOW\model\gis\empty folder.
<li>Save the empty layer as '''1d_nwke_X1DQ_P.shp''' in the '''TUFLOW\model\gis folder'''.
<li>Turn on Toggle Editing for the layer '''1d_nwke_X1DQ_P.shp''' and add the attribute values shown in the table below.
{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| ID || ds2 (remember that Flood Modeller is case sensitive)
|-
| Type || Node
|-
| Conn_1D_2D || X1DQ
|}

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS SHP Part3.mp4 |width=1123}} 

=Conclusion=

The ESTRY pipe network for the proposed development has been connected via an "X1DH" link to discharge via two pipes into the Flood Modeller network by snapping together the nodes in a 1d_nwk_L layer to a node in the 1d_x1d_P layer. A 1d_nwk_L layer has been added to represent the open channel network downstream of the Flood Modeller network in ESTRY. The cross section data for this open channel network has been defined by adding a 1d_xs_L layer with links to the source csv files at every cross section location. A connector "X" type channel and a 1d_nwke_P layer have been added to connect the ESTRY and Flood Modeller open channel networks via an "X1DQ" link. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Modify Simulation Control Files | Flood Modeller Tutorial 2]].

</ol>

FM Tutorial M02 QGIS SHP Boundary Conditions

2025-09-26T14:47:11Z

Tuflowduncan:

<ol>
=Introduction=
This page details the method for using QGIS to create the GIS based boundary layer. The layer will be populated with the name of each inflow boundary which will be linked to the boundary database in the following steps of this module. The created boundary will be applied as a source-area boundary in a 2d_sa layer. 
=Method=
'''Boundary Condition Database'''
<li>Copy the file '''100yr2hr_loc.csv''' from '''Module_data\Module_02\Inflow''' and place it into the '''TUFLOW\model\bc_dbase''' folder. This file contains the four hydrographs that will be used.
<li>Open up the latest version of the boundary condition database. This is located within the '''TUFLOW\model\bc_dbase folder''' and is called '''bc_dbase_FMT_M01.csv'''.
<li>We need to add four additional rows to the file which reference four additional inflows. The revised bc_dbase should look like the figure below: 
 
[[File:100yr2hr_loc_csv.png]] 
 
The hydrographs applied to each of the 2d_sa polygons are contained within the source file '''100yr2hr_loc.csv'''. 
[[File:100yr2hr loc.PNG|800px]]
 
<li>Save the bc_dbase as '''bc_dbase_FMT_M02.csv'''. It is now ready to be used within the model.
 
<li>Copy the layer '''2d_sa_FMT_M02_001_R.shp''' within the '''Module_data\Module_02\Inflow''' folder into the '''TUFLOW\model\gis''' folder.
<li>Open the layer in QGIS. Four polygons have been digitised over the location of the proposed development. Each polygon represents a sub-catchment to which different inflow boundaries will be associated.
<li>Turn on Toggle Editing mode. Populate the first and only attribute of each polygon with the name of the inflow boundary . The next steps of this module will link these boundary names with an inflow using the bc_dbase located in '''TUFLOW\bc_dbase''' . 
 
[[File:M07 SA polygons QGIS.png|700px]]

 {{Video|name= Define_Boundary_Conditions_Module_02_QGIS_SHP.mp4 |width=1123}} 

<li>Save the layer '''2d_sa_FMT_M02_001_R'''. 

=Conclusion=
A GIS layer has been created containing four polygons in a 2d_sa layer over the location of the proposed development. The existing boundary conditions database (bc_dbase) has been modified to link these four GIS objects to hydrographs within an external csv file. Please return to the main page of the [[Flood Modeller Tutorial Module02_Provisional#Flood Modeller 1D/ESTRY 1D Link | Flood Modeller Tutorial 2]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

</ol>

File:X1dh.png

2025-09-26T14:40:23Z

Tuflowduncan:

X1DH Flows

File:X1dq.png

2025-09-26T14:39:24Z

Tuflowduncan:

X1DQ Flows

FM Tutorial M01 QGIS GPKG 1D2D Code

2025-09-25T18:03:33Z

Tuflowduncan: /* Method */

<ol>
=Introduction=
In this section we will deactivate the 2D cells where the 1D Flood Modeller component is replacing the 2D representation of the open channel. The width of the deactivated 2D area should be approximately equal to the width of the 1D cross-sections. This step essentially replaces the conveyance of the deactivated 2D area with an equivalent 1D conveyance.

=Method=
<li>Import in an empty 2d_bc_empty_R.gpkg layer from within the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis\empty''' folder.</li>
<li>Save the layer as 2d_bc_FMT_M01_HX_001_R.gpkg in the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis''' folder. </li>
<li>Move the empty 2d_bc layer 2d_bc_FMT_M01_HX_001_R.gpkg into the project GeoPackage file M02_5m_002.gpkg in the Browser Panel. Load the empty layer 2d_bc_FMT_M01_HX_001_R into QGIS from M02_5m_002.gpkg.</li>
<li>Open the Inactive_area.shp GIS layer from '''Module_Data\Module_01\shp''' folder. Select all objects from within this layer, copy and paste into 2d_bc_FMT_M01_HX_001_R. </li>
<li> For all polygons assign a 'type' attribute of 'CD'. This designates the digitised polygon as a code polygon where the 2D cells within it may be either active or inactive. </li>
<li> For all polygons assign a 'f' attribute of '-1'. A cell code of '-1' deactivates all cells within the digitised code polygons.
Cells may also be deactivated within a model by using a cell code of '0' instead of '-1'. A value of 0 removes these cells from the computation entirely which has the benefit of reducing computation time and output file sizes.</li>

<li> Observe how the code polygon has been digitised between nodes FC01.35 and FC01.34. The polygon covers the area between these two Flood Modeller nodes. This is because overtopping of the embankment at this location has been represented in the 1D Flood Modeller component of the model.</li>

<li> Observe how the code polygon has been digitised downstream of node FC01.11. In this case, no code polygon has been digitised over the embankment. This is because overtopping of the embankment will be modelled in the 2D TUFLOW component of the model. The '''2d_bc_FMT_M01_HX_001_L''' layer created previously contains additional HX boundary polylines at the upstream and downstream faces of the embankment to allow for overtopping.</li>

 {{Video|name= Deactivate 2D cells GPKG.mp4 |width=1123}} 

<li>Save the file</li>

 Please return to the [[Flood_Modeller_Tutorial_Module01_Provisional#Modify_Simulation_Control_Files|Flood Modeller Tutorial Model]].
{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module01_Provisional| Back to Tutorial Module 01 Main Page]]
}}
</ol>

FM Tutorial M01 QGIS SHP 1D2D Code

2025-09-25T18:03:22Z

Tuflowduncan: /* Method */

<ol>
=Introduction=
In this section we will deactivate the 2D cells where the 1D Flood Modeller component is replacing the 2D representation of the open channel. The width of the deactivated 2D area should be approximately equal to the width of the 1D cross-sections. This step essentially replaces the conveyance of the deactivated 2D area with an equivalent 1D conveyance.

=Method=
<li>Import in an empty 2d_bc_empty_R.shp layer from within the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis\empty''' folder.</li>
<li>Save the layer as 2d_bc_FMT_M01_HX_001_R.shp in the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis''' folder. </li>
<li>Open the Inactive_area.shp GIS layer from '''Module_Data\Module_01\shp''' folder. Select all objects from within this layer, copy and paste into 2d_bc_FMT_M01_HX_001_R.shp. </li>
<li> For all polygons assign a 'type' attribute of 'CD'. This designates the digitised polygon as a code polygon where the 2D cells within it may be either active or inactive. </li>
<li> For all polygons assign a 'f' attribute of '-1'. A cell code of '-1' deactivates all cells within the digitised code polygons.
Cells may also be deactivated within a model by using a cell code of '0' instead of '-1'. A value of 0 removes these cells from the computation entirely which has the benefit of reducing computation time and output file sizes.</li>

<li> Observe how the code polygon has not been digitised between nodes FC01.35 and FC01.34. The polygon covers the area between these two Flood Modeller nodes. This is because overtopping of the embankment at this location has been represented in the 1D Flood Modeller component of the model.</li>

<li> Observe how the code polygon has been digitised downstream of node FC01.11. In this case, no code polygon has been digitised over the embankment. This is because overtopping of the embankment will be modelled in the 2D TUFLOW component of the model. The '''2d_bc_FMT_M01_HX_001_L.shp''' layer created previously contains additional HX boundary polylines at the upstream and downstream faces of the embankment to allow for overtopping.</li>

 {{Video|name= Deactivate 2D cells SHP.mp4 |width=1123}} 

<li>Save the file</li>

 Please return to the [[Flood_Modeller_Tutorial_Module01_Provisional#Modify_Simulation_Control_Files|Flood Modeller Tutorial Model]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module01_Provisional| Back to Tutorial Module 01 Main Page]]
}}
</ol>

FM Tutorial M01 QGIS GPKG 1D2D Links

2025-09-25T18:03:13Z

Tuflowduncan: /* Method */

<ol>

=Introduction=
In this section we will set up the Flood Modeller-TUFLOW linkage to apply a water level boundary to the 2D cells along the 1D/2D interface. In the 2D boundary condition (2d_bc) GIS layer, we define the location at which this link occurs. The 2D water level applied at the 2D boundary cells is calculated in the 1D Flood Modeller engine. The terminology used in TUFLOW is a '''HX''' type boundary on the 2D cells, with the '''H''' indicating that a '''H'''ead (water level) boundary is used and the '''X''' indicating the value is coming from an e'''X'''ternal model (in this case Flood Modeller).
Depending on the water level in the surrounding 2D cells, flow can either enter or leave the HX cells. The volume of water entering or leaving the 2D boundary is added or subtracted from the 1D Flood Modeller model to preserve volume. We must connect the HX lines to the 1D Flood Modeller model. This is done using CN type lines in the 2d_bc layer, where a CN line is connected to the HX line, the water level from the 1D Flood Modeller nodes is transferred to the HX line. In between 1D nodes, a linear interpolation of water level is applied. This is shown in the figure below.
 
[[File:1d 2d FM link 01.jpg|800px]]
 
Once the water level in Flood Modeller exceeds the elevation in the boundary cell water can enter or leave the model. Similar to a Flood Modeller lateral spill or lateral inflow, the discharge is distributed laterally along the length of the HX line. Note that it is the elevation of the HX boundary cell centres that determines when the spill starts to occur and not the cross section within Flood Modeller. If there is a levee or flood defence, it is important that we use breaklines in the model to ensure that the elevations of the 2D cells are consistent with the levee crest. This will be described in the next section of the tutorial. The next four images show a section view of the 1D/2D link and how this may progress during a flood event. 
 
[[File:M04 1d2d 01.png|300px]]
[[File:M04 1d2d 02.png|300px]]
[[File:M04 1d2d 03.png|300px]]
[[File:M04 1d2d 04.png|300px]]
 The digitised direction of the HX and CN lines are not important. The CN lines however should be digitised approximately perpendicular to the direction of flow. Two CN lines are digitised for each node and connected to the HX boundary lines along the left and right banks. The HX boundary lines should be digitised along the top of each bank such that the width between the lines approximately correlates to the width of the 1D channel. .
 Often HX lines are located along the top of a levee (natural or artificial) or flood defence running along the river bank. When carving a 1D channel through a 2D domain, the HX line must be either on the top of the levee or on the inside of the levee (closest to the channel). If the HX line is located on the other side of the levee away from the channel, the effect of the levee on water flow is '''not''' modelled. In the sections above, it can be seen that the boundary cell is along the levee and the interaction between the channel and the floodplain (1D and 2D) occurs at the correct elevation. 
 Where there are junctions within the Flood Modeller 1D model (i.e. at structures), both the nodes immediately upstream and downstream must be connected to TUFLOW. The HX lines must be broken between the junctions as this is a requirement of a linked Flood Modeller – TUFLOW model .
 The generation of the 1D-2D links for Flood Modeller – TUFLOW models can be partially automated through the use of the [https://help.floodmodeller.com/v1/docs/how-to-use-the-tuflow-link-lines-generator-tool TUFLOW Link Line] tool in Flood Modeller. Guidance on how to use this tool can be found on the Flood Modeller [https://help.floodmodeller.com/docs/how-to-use-the-tuflow-link-lines-generator-tool website]. Note, that this will currently only generate Shaepfiles which would need to be imported into the Geopackage format.

=Method=
<li>Import in an empty 2d_bc_empty_L.gpkg layer from within the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis\empty''' folder. </li>
<li>Save the empty layer as 2d_bc_FMT_M01_HX_001_L.gpkg in the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis''' folder.</li>
<li>Move the empty 2d_bc layer 2d_bc_FMT_M01_HX_001_L.gpkg into the project GeoPackage file M02_5m_002.gpkg in the Browser Panel. Load the empty layer 2d_bc_FMT_M01_HX_001_L.gpkg into QGIS from M02_5m_002.gpkg. </li>
<li>Open the 1D_2D_HX_Links_L.shp GIS layer from '''Module_Data\Module_01\gis''' folder. Select all objects from within this layer, copy and paste into 2d_bc_FMT_M01_HX_001_L .</li>
<li>Interrogate one of the lines running along the banks of the watercourse. These lines are the 1D/2D boundary links and have been assigned a type ‘HX’.</li>
<li>Interrogate one of the lines connecting the x1D node to the HX line. These are the connection or ‘CN’ lines that read the water level from Flood Modeller and transfers this to the HX line. </li>
 {{Video|name= Define 1D 2D Bdy Links 01 GPKG.mp4 |width=1123}} 

In the figure below, the water level is calculated in Flood Modeller at the nodes FC01.16, FC01.15 and FC01.14. These water levels are linearly interpolated along the lengths of the HX line on each of the left and right banks of the watercourse. When the water level exceeds the ZC elevation of the boundary cell, water is able to flow out onto the TUFLOW 2D floodplain. 
 
[[File:FMT 1D-2D Linking QGIS.JPG|600px]]
 
Note that where there are junctions within the Flood Modeller 1D model (i.e. at structures), both the nodes immediately upstream and downstream must be connected to TUFLOW. Refer to the below figure where the junctions are circled in blue and the upstream and downstream RIVER units are circled in yellow. The HX lines must be broken between the junctions as this is a requirement of a linked Flood Modeller – TUFLOW model.
In the example below, the HX lines are broken between FC01.35 and FC01.34 as a culvert is located between these nodes.
 
[[File:FM_junction.jpg|540x540px|alt=]]
[[File:FMT 1D-2D Broken HX Line.JPG|540x540px|alt=]]

<li>The CN and HX lines between nodes FC02.06 and FC02.01d along the tributary have not been digitised. Digitise these lines to connect the nodes to the 2D domain. 
To digitise the CN lines, make the 2d_bc_FMT_M01_HX_001_L layer editable and ensure snapping has been turned on. For each node in the 1d_x1d_FMT_M01_nodes_001_P layer, draw a line from the node to the HX line. The line must snap to both the node and the HX line, so it is recommended to use the snapping tool. Draw two lines for each node, one to the left bank and one to the right bank. In the 'Type' attribute of each line, type 'CN'. Assign the digitised CN lines an ‘f' attribute’ of ‘1’. This sets the weighting to be applied in distributing the water level from the 1D node to the 2D cell. 
 {{Video|name=Define 1D 2D Bdy Links 02 SHP.mp4 |width=1123}} 

 The figure below shows how the nodes are connected at the confluence. Note that all Flood Modeller nodes at the junction are present within the 1d_x1D_nodes layer, and are connected to the 2D domain. The HX lines are broken around the junction. </li>
 
[[File:FMT 1D-2D Linking Junction QGIS.JPG|900px]]

<li>Once all the CN and HX lines have been digitised along the tributary, save the file.</li>

 Please return to the [[Flood_Modeller_Tutorial_Module01_Provisional#Define_Bank_Elevations|Flood Modeller Tutorial Model]]. 

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module01_Provisional| Back to Tutorial Module 01 Main Page]]
}}
</ol>

FM Tutorial M01 QGIS SHP 1D2D Links

2025-09-25T18:02:59Z

Tuflowduncan: /* Method */

<ol>
=Introduction=
In this section we will set up the Flood Modeller-TUFLOW linkage to apply a water level boundary to the 2D cells along the 1D/2D interface. In the 2D boundary condition (2d_bc) GIS layer, we define the location at which this link occurs. The 2D water level applied at the 2D boundary cells is calculated in the 1D Flood Modeller component. The terminology used in TUFLOW is a '''HX''' type boundary on the 2D cells, with the '''H''' indicating that a '''H'''ead (water level) boundary is used and the '''X''' indicating the value is coming from an e'''X'''ternal model (in this case Flood Modeller).
Depending on the water level in the surrounding 2D cells, flow can either enter or leave the HX cells. The volume of water entering or leaving the 2D boundary is added or subtracted from the 1D Flood Modeller model to preserve volume. We must connect the HX lines to the 1D Flood Modeller model. This is done using CN type lines in the 2d_bc layer, where a CN line is connected to the HX line, the water level from the 1D Flood Modeller nodes is transferred to the HX line. In between 1D nodes, a linear interpolation of water level is applied. This is shown in the figure below.
 
[[File:1d 2d FM link 01.jpg|800px]]
 
Once the water level in Flood Modeller exceeds the elevation in the boundary cell water can enter or leave the model. Similar to a Flood Modeller lateral spill or lateral inflow, the discharge is distributed laterally along the length of the HX line. Note that it is the elevation of the HX boundary cell centres that determines when the spill starts to occur and not the cross section within Flood Modeller. If there is a levee or flood defence, it is important that we use breaklines in the model to ensure that the elevations of the 2D cells are consistent with the levee crest. This will be described in the next section of the tutorial. The next four images show a section view of the 1D/2D link and how this may progress during a flood event. 
 
[[File:M04 1d2d 01.png|300px]]
[[File:M04 1d2d 02.png|300px]]
[[File:M04 1d2d 03.png|300px]]
[[File:M04 1d2d 04.png|300px]]
 The digitised direction of the HX and CN lines are not important. The CN lines however should be digitised approximately perpendicular to the direction of flow. Two CN lines are digitised for each node and connected to the HX boundary lines along the left and right banks. The HX boundary lines should be digitised along the top of each bank such that the width between the lines approximately correlates to the width of the 1D channel. .
 Often HX lines are located along the top of a levee (natural or artificial) or flood defence running along the river bank. When carving a 1D channel through a 2D domain, the HX line must be either on the top of the levee or on the inside of the levee (closest to the channel). If the HX line is located on the other side of the levee away from the channel, the effect of the levee on water flow is '''not''' modelled. In the sections above, it can be seen that the boundary cell is along the levee and the interaction between the channel and the floodplain (1D and 2D) occurs at the correct elevation. 
 Where there are junctions within the Flood Modeller 1D model (i.e. at structures), both the nodes immediately upstream and downstream must be connected to TUFLOW. The HX lines must be broken between the junctions as this is a requirement of a linked Flood Modeller – TUFLOW model .
 The generation of the 1D-2D links for Flood Modeller – TUFLOW models can be partially automated through the use of the TUFLOW Link Line tool in Flood Modeller Pro. Guidance on how to use this tool can be found on the Flood Modeller Pro [https://help.floodmodeller.com/docs/how-to-use-the-tuflow-link-lines-generator-tool website ]. 

=Method=
<li>Import in an empty 2d_bc_empty_L.shp layer from within the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis\empty''' folder. </li>
<li>Save the empty layer as 2d_bc_FMT_M01_HX_001_L.shp in the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis''' folder.</li>
<li>Open the 1D_2D_HX_Links_L.shp GIS layer from '''Module_Data\Module_01\gis''' folder. Select all objects from within this layer, copy and paste into 2d_bc_FMT_M01_HX_001_L.shp.</li>
<li>Interrogate one of the lines running along the banks of the watercourse. These lines are the 1D/2D boundary links and have been assigned a type ‘HX’.</li>
<li>Interrogate one of the lines connecting the x1D node to the HX line. These are the connection or ‘CN’ lines that read the water level from Flood Modeller and transfers this to the HX line. </li>
 {{Video|name= Define 1D 2D Bdy Links 01 SHP.mp4 |width=1123}} 

In the figure below, the water level is calculated in Flood Modeller at the nodes FC01.16, FC01.15 and FC01.14. These water levels are linearly interpolated along the lengths of the HX line on each of the left and right banks of the watercourse. When the water level exceeds the ZC elevation of the boundary cell, water is able to flow out onto the TUFLOW 2D floodplain. 
 
[[File:FMT 1D-2D Linking QGIS.JPG|600px]]
 
Note that where there are junctions within the Flood Modeller 1D model (i.e. at structures), both the nodes immediately upstream and downstream must be connected to TUFLOW. Refer to the below figure where the junctions are circled in blue and the upstream and downstream RIVER units are circled in yellow. The HX lines must be broken between the junctions as this is a requirement of a linked Flood Modeller – TUFLOW model.
In the example below, the HX lines are broken between FC01.35 and FC01.34 as a culvert is located between these nodes.
 
[[File:FM_junction.jpg|540x540px|alt=]]
[[File:FMT 1D-2D Broken HX Line.JPG|540x540px|alt=]]

<li>The CN and HX lines between nodes FC02.06 and FC02.01d along the tributary have not been digitised. Digitise these lines to connect the nodes to the 2D domain. 
To digitise the CN lines, make the 2d_bc_FMT_M01_HX_001_L.shp layer editable and ensure snapping has been turned on. For each node in the 1d_x1d_FMT_M01_nodes_001_P.shp layer, draw a line from the node to the HX line. The line must snap to both the node and the HX line, so it is recommended to use the snapping tool. Draw two lines for each node, one to the left bank and one to the right bank. In the 'Type' attribute of each line, type 'CN'. Assign the digitised CN lines an ‘f' attribute’ of ‘1’. This sets the weighting to be applied in distributing the water level from the 1D node to the 2D cell. 
 {{Video|name=Define 1D 2D Bdy Links 02 SHP.mp4 |width=1123}} 

 The figure below shows how the nodes are connected at the confluence. Note that all Flood Modeller nodes at the junction are present within the 1d_x1D_nodes layer, and are connected to the 2D domain. The HX lines are broken around the junction. </li>
 
[[File:FMT 1D-2D Linking Junction QGIS.JPG|900px]]

<li>Once all the CN and HX lines have been digitised along the tributary, save the file.</li>

 Please return to the [[Flood_Modeller_Tutorial_Module01_Provisional#Define_Bank_Elevations|Flood Modeller Tutorial Model]]. 

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module01_Provisional| Back to Tutorial Module 01 Main Page]]
}}
</ol>

FM Tutorial M01 QGIS SHP 1D2D Links

2025-09-25T18:02:49Z

Tuflowduncan: /* Introduction */

<ol>
=Introduction=
In this section we will set up the Flood Modeller-TUFLOW linkage to apply a water level boundary to the 2D cells along the 1D/2D interface. In the 2D boundary condition (2d_bc) GIS layer, we define the location at which this link occurs. The 2D water level applied at the 2D boundary cells is calculated in the 1D Flood Modeller component. The terminology used in TUFLOW is a '''HX''' type boundary on the 2D cells, with the '''H''' indicating that a '''H'''ead (water level) boundary is used and the '''X''' indicating the value is coming from an e'''X'''ternal model (in this case Flood Modeller).
Depending on the water level in the surrounding 2D cells, flow can either enter or leave the HX cells. The volume of water entering or leaving the 2D boundary is added or subtracted from the 1D Flood Modeller model to preserve volume. We must connect the HX lines to the 1D Flood Modeller model. This is done using CN type lines in the 2d_bc layer, where a CN line is connected to the HX line, the water level from the 1D Flood Modeller nodes is transferred to the HX line. In between 1D nodes, a linear interpolation of water level is applied. This is shown in the figure below.
 
[[File:1d 2d FM link 01.jpg|800px]]
 
Once the water level in Flood Modeller exceeds the elevation in the boundary cell water can enter or leave the model. Similar to a Flood Modeller lateral spill or lateral inflow, the discharge is distributed laterally along the length of the HX line. Note that it is the elevation of the HX boundary cell centres that determines when the spill starts to occur and not the cross section within Flood Modeller. If there is a levee or flood defence, it is important that we use breaklines in the model to ensure that the elevations of the 2D cells are consistent with the levee crest. This will be described in the next section of the tutorial. The next four images show a section view of the 1D/2D link and how this may progress during a flood event. 
 
[[File:M04 1d2d 01.png|300px]]
[[File:M04 1d2d 02.png|300px]]
[[File:M04 1d2d 03.png|300px]]
[[File:M04 1d2d 04.png|300px]]
 The digitised direction of the HX and CN lines are not important. The CN lines however should be digitised approximately perpendicular to the direction of flow. Two CN lines are digitised for each node and connected to the HX boundary lines along the left and right banks. The HX boundary lines should be digitised along the top of each bank such that the width between the lines approximately correlates to the width of the 1D channel. .
 Often HX lines are located along the top of a levee (natural or artificial) or flood defence running along the river bank. When carving a 1D channel through a 2D domain, the HX line must be either on the top of the levee or on the inside of the levee (closest to the channel). If the HX line is located on the other side of the levee away from the channel, the effect of the levee on water flow is '''not''' modelled. In the sections above, it can be seen that the boundary cell is along the levee and the interaction between the channel and the floodplain (1D and 2D) occurs at the correct elevation. 
 Where there are junctions within the Flood Modeller 1D model (i.e. at structures), both the nodes immediately upstream and downstream must be connected to TUFLOW. The HX lines must be broken between the junctions as this is a requirement of a linked Flood Modeller – TUFLOW model .
 The generation of the 1D-2D links for Flood Modeller – TUFLOW models can be partially automated through the use of the TUFLOW Link Line tool in Flood Modeller Pro. Guidance on how to use this tool can be found on the Flood Modeller Pro [https://help.floodmodeller.com/docs/how-to-use-the-tuflow-link-lines-generator-tool website ]. 

=Method=
<li>Import in an empty 2d_bc_empty_L.shp layer from within the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis\empty''' folder. </li>
<li>Save the empty layer as 2d_bc_FMT_M01_HX_001_L.shp in the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis''' folder.</li>
<li>Open the 1D_2D_HX_Links_L.shp GIS layer from '''Module_Data\Module_01\gis''' folder. Select all objects from within this layer, copy and paste into 2d_bc_FMT_M01_HX_001_L.shp.</li>
<li>Interrogate one of the lines running along the banks of the watercourse. These lines are the 1D/2D boundary links and have been assigned a type ‘HX’.</li>
<li>Interrogate one of the lines connecting the x1D node to the HX line. These are the connection or ‘CN’ lines that read the water level from Flood Modeller and transfers this to the HX line. </li>
 {{Video|name= Define 1D 2D Bdy Links 01 SHP.mp4 |width=1123}} 

In the figure below, the water level is calculated in Flood Modeller at the nodes FC01.16, FC01.15 and FC01.14. These water levels are linearly interpolated along the lengths of the HX line on each of the left and right banks of the watercourse. When the water level exceeds the ZC elevation of the boundary cell, water is able to flow out onto the TUFLOW 2D floodplain. 
 
[[File:FMT 1D-2D Linking QGIS.JPG|600px]]
 
Note that where there are junctions within the Flood Modeller 1D model (i.e. at structures), both the nodes immediately upstream and downstream must be connected to TUFLOW. Refer to the below figure where the junctions are circled in blue and the upstream and downstream RIVER units are circled in yellow. The HX lines must be broken between the junctions as this is a requirement of a linked Flood Modeller – TUFLOW model.
In the example below, the HX lines are broken between FC01.35 and FC01.34 as a culvert is located between these nodes.
 
[[File:FM_junction.jpg|540x540px|alt=]]
[[File:FMT 1D-2D Broken HX Line.JPG|540x540px|alt=]]

<li>The CN and HX lines between nodes FC02.06 and FC02.01d along the tributary have not been digitised. Digitise these lines to connect the nodes to the 2D domain. 
To digitise the CN lines, make the 2d_bc_FMT_M01_HX_001_L.shp layer editable and ensure snapping has been turned on. For each node in the 1d_x1d_FMT_M01_nodes_001_P.shp layer, draw a line from the node to the HX line. The line must snap to both the node and the HX line, so it is recommended to use the snapping tool. Draw two lines for each node, one to the left bank and one to the right bank. In the 'Type' attribute of each line, type 'CN'. Assign the digitised CN lines an ‘f' attribute’ of ‘1’. This sets the weighting to be applied in distributing the water level from the 1D node to the 2D cell. 
 {{Video|name=Define 1D 2D Bdy Links 02 SHP.mp4 |width=1123}} 

 The figure below shows how the nodes are connected at the confluence. Note that all Flood Modeller nodes at the junction are present within the 1d_x1D_nodes layer, and are connected to the 2D domain. The HX lines are broken around the junction. </li>
 
[[File:FMT 1D-2D Linking Junction QGIS.JPG|900px]]

<li>Once all the CN and HX lines have been digitised along the tributary, save the file.</li>

 Please return to the [[Flood_Modeller_Tutorial_Module01_Provisional#Define_Bank_Elevations|Flood Modeller Tutorial Model]]. 

</ol>

FM Tutorial M01 QGIS SHP 1D2D Links

2025-09-25T18:02:36Z

Tuflowduncan: /* Introduction */

<ol>
=Introduction=
In this section we will set up the Flood Modeller-TUFLOW linkage to apply a water level boundary to the 2D cells along the 1D/2D interface. In the 2D boundary condition (2d_bc) GIS layer, we define the location at which this link occurs. The 2D water level applied at the 2D boundary cells is calculated in the 1D Flood Modeller component. The terminology used in TUFLOW is a '''HX''' type boundary on the 2D cells, with the '''H''' indicating that a '''H'''ead (water level) boundary is used and the '''X''' indicating the value is coming from an e'''X'''ternal model (in this case Flood Modeller).
Depending on the water level in the surrounding 2D cells, flow can either enter or leave the HX cells. The volume of water entering or leaving the 2D boundary is added or subtracted from the 1D Flood Modeller model to preserve volume. We must connect the HX lines to the 1D Flood Modeller model. This is done using CN type lines in the 2d_bc layer, where a CN line is connected to the HX line, the water level from the 1D Flood Modeller nodes is transferred to the HX line. In between 1D nodes, a linear interpolation of water level is applied. This is shown in the figure below.
 
[[File:1d 2d FM link 01.jpg|800px]]
 
Once the water level in Flood Modeller exceeds the elevation in the boundary cell water can enter or leave the model. Similar to a Flood Modeller lateral spill or lateral inflow, the discharge is distributed laterally along the length of the HX line. Note that it is the elevation of the HX boundary cell centres that determines when the spill starts to occur and not the cross section within Flood Modeller. If there is a levee or flood defence, it is important that we use breaklines in the model to ensure that the elevations of the 2D cells are consistent with the levee crest. This will be described in the next section of the tutorial. The next four images show a section view of the 1D/2D link and how this may progress during a flood event. 
 
[[File:M04 1d2d 01.png|300px]]
[[File:M04 1d2d 02.png|300px]]
[[File:M04 1d2d 03.png|300px]]
[[File:M04 1d2d 04.png|300px]]
 The digitised direction of the HX and CN lines are not important. The CN lines however should be digitised approximately perpendicular to the direction of flow. Two CN lines are digitised for each node and connected to the HX boundary lines along the left and right banks. The HX boundary lines should be digitised along the top of each bank such that the width between the lines approximately correlates to the width of the 1D channel. .
 Often HX lines are located along the top of a levee (natural or artificial) or flood defence running along the river bank. When carving a 1D channel through a 2D domain, the HX line must be either on the top of the levee or on the inside of the levee (closest to the channel). If the HX line is located on the other side of the levee away from the channel, the effect of the levee on water flow is '''not''' modelled. In the sections above, it can be seen that the boundary cell is along the levee and the interaction between the channel and the floodplain (1D and 2D) occurs at the correct elevation. 
 Where there are junctions within the Flood Modeller 1D model (i.e. at structures), both the nodes immediately upstream and downstream must be connected to TUFLOW. The HX lines must be broken between the junctions as this is a requirement of a linked Flood Modeller – TUFLOW model .
 The generation of the 1D-2D links for Flood Modeller – TUFLOW models can be partially automated through the use of the TUFLOW Link Line tool in Flood Modeller Pro. Guidance on how to use this tool can be found on the Flood Modeller Pro [https://help.floodmodeller.com/docs/how-to-use-the-tuflow-link-lines-generator-tool website ]. 

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module01_Provisional| Back to Tutorial Module 01 Main Page]]
}}

=Method=
<li>Import in an empty 2d_bc_empty_L.shp layer from within the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis\empty''' folder. </li>
<li>Save the empty layer as 2d_bc_FMT_M01_HX_001_L.shp in the '''FMT_tutorial\FMT_M01\TUFLOW\model\gis''' folder.</li>
<li>Open the 1D_2D_HX_Links_L.shp GIS layer from '''Module_Data\Module_01\gis''' folder. Select all objects from within this layer, copy and paste into 2d_bc_FMT_M01_HX_001_L.shp.</li>
<li>Interrogate one of the lines running along the banks of the watercourse. These lines are the 1D/2D boundary links and have been assigned a type ‘HX’.</li>
<li>Interrogate one of the lines connecting the x1D node to the HX line. These are the connection or ‘CN’ lines that read the water level from Flood Modeller and transfers this to the HX line. </li>
 {{Video|name= Define 1D 2D Bdy Links 01 SHP.mp4 |width=1123}} 

In the figure below, the water level is calculated in Flood Modeller at the nodes FC01.16, FC01.15 and FC01.14. These water levels are linearly interpolated along the lengths of the HX line on each of the left and right banks of the watercourse. When the water level exceeds the ZC elevation of the boundary cell, water is able to flow out onto the TUFLOW 2D floodplain. 
 
[[File:FMT 1D-2D Linking QGIS.JPG|600px]]
 
Note that where there are junctions within the Flood Modeller 1D model (i.e. at structures), both the nodes immediately upstream and downstream must be connected to TUFLOW. Refer to the below figure where the junctions are circled in blue and the upstream and downstream RIVER units are circled in yellow. The HX lines must be broken between the junctions as this is a requirement of a linked Flood Modeller – TUFLOW model.
In the example below, the HX lines are broken between FC01.35 and FC01.34 as a culvert is located between these nodes.
 
[[File:FM_junction.jpg|540x540px|alt=]]
[[File:FMT 1D-2D Broken HX Line.JPG|540x540px|alt=]]

<li>The CN and HX lines between nodes FC02.06 and FC02.01d along the tributary have not been digitised. Digitise these lines to connect the nodes to the 2D domain. 
To digitise the CN lines, make the 2d_bc_FMT_M01_HX_001_L.shp layer editable and ensure snapping has been turned on. For each node in the 1d_x1d_FMT_M01_nodes_001_P.shp layer, draw a line from the node to the HX line. The line must snap to both the node and the HX line, so it is recommended to use the snapping tool. Draw two lines for each node, one to the left bank and one to the right bank. In the 'Type' attribute of each line, type 'CN'. Assign the digitised CN lines an ‘f' attribute’ of ‘1’. This sets the weighting to be applied in distributing the water level from the 1D node to the 2D cell. 
 {{Video|name=Define 1D 2D Bdy Links 02 SHP.mp4 |width=1123}} 

 The figure below shows how the nodes are connected at the confluence. Note that all Flood Modeller nodes at the junction are present within the 1d_x1D_nodes layer, and are connected to the 2D domain. The HX lines are broken around the junction. </li>
 
[[File:FMT 1D-2D Linking Junction QGIS.JPG|900px]]

<li>Once all the CN and HX lines have been digitised along the tributary, save the file.</li>

 Please return to the [[Flood_Modeller_Tutorial_Module01_Provisional#Define_Bank_Elevations|Flood Modeller Tutorial Model]]. 

</ol>

FM Tutorial M01 QGIS GPKG x1D Nodes

2025-09-25T18:02:25Z

Tuflowduncan: /* Method */

<ol>
=Introduction=
We will now create a TUFLOW GIS layer to reference the external 1D nodes within the Flood Modeller model network. The purpose of this layer is to specify the spatial location of each of the linked Flood Modeller nodes. This allows TUFLOW to read the water levels from the Flood Modeller model and apply them to the TUFLOW domains as 2D water level boundaries.

=Method=

<li> Open the FloodModeller_Nodes_P.shp layer from the Module_Data\Module_01\gis folder.</li>
<li> Save as 1d_x1d_FMT_M01_nodes_001_P.gpkg within the FMT_tutorial\FMT_M01\TUFLOW\model\gis folder. </li>
<li> Move the GIS layer 1d_x1d_FMT_M01_nodes_001_P.gpkg into the project GeoPackage file M02_5m_002.gpkg in the Browser Panel. </li>
<li>Reload the layer 1d_x1d_FMT_M01_nodes_001_P in QGIS from M02_5m_002.gpkg.</li>
<li> Open the attribute table. This layer only has a single attribute correlating to the unique Node ID of a RIVER, INTERPOLATE or REPLICATE unit within the Flood Modeller model. Note that the Node IDs are case-sensitive as this is a requirement of Flood Modeller. At junctions, both the upstream and downstream nodes must be digitised within this layer. It is often helpful to label the Node IDs.</li>

 {{Video|name= Define External 1D Networks GPKG v2.mp4 |width=1123}} 

 In recent versions of Flood Modeller, it is possible to export the nodes to a TUFLOW Shapefile using the Export->Nodes as TUFLOW Shapefile tool. This can then be imported into the Geopackage file format as the 1d_X1D layer. It should however be noted that the model should be correctly georeferenced within Flood Modeller which isn't always the case. The georeferencing of a model network can be a time-consuming process and should be considered at the project outset. 

 You have now created the GIS layer representing the Flood Modeller nodes for reading into TUFLOW. Return to the [[Flood_Modeller_Tutorial_Module01_Provisional#Define_the_1D/2D_Boundary Links|Flood Modeller Tutorial Model]]. 

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module01_Provisional| Back to Tutorial Module 01 Main Page]]
}}
</ol>

FM Tutorial M01 QGIS SHP x1D Nodes

2025-09-25T18:02:15Z

Tuflowduncan: /* Method */

== Introduction ==
Create a TUFLOW GIS layer to reference the external 1D nodes within the Flood Modeller model network.

The layer specifies the spatial location of each linked Flood Modeller node, allowing TUFLOW to read water levels from the Flood Modeller model and apply them to the TUFLOW domains as 2D water level boundaries.

== Method ==

1. Open the FloodModeller_Nodes_P.shp layer from the Module_Data\Module_01\gis folder.

2. Save as 1d_x1d_FMT_M01_nodes_001_P.shp within the FMT_M01\TUFLOW\model\gis folder. {{Video|name=Define_External_1D_Networks_SHP.mp4 |width=1123}}

3. Open the GIS layer 1d_x1d_FMT_M01_nodes_001_P.shp within QGIS.

4. Open the attribute table. This layer only has a single attribute correlating to the unique Node ID of a RIVER, INTERPOLATE or REPLICATE unit within the Flood Modeller model. Note that the node IDs are case-sensitive as this is a requirement of Flood Modeller. At junctions, both the upstream and downstream nodes must be digitised within this layer. It is often helpful to label the Node IDs.

In recent versions of Flood Modeller, it is possible to export the nodes to a TUFLOW Shapefile using the Export->Nodes as TUFLOW Shapefile tool. This can then be used as the 1d_X1D layer. It should however be noted that the model should be correctly georeferenced within Flood Modeller which isn't always the case. The georeferencing of a model network can be a time-consuming process and should be considered at the project outset.

After creating the GIS layer representing the Flood Modeller nodes for reading into TUFLOW, return to the [[Flood_Modeller_Tutorial_Module01_Provisional#Define_the_1D/2D_Boundary Links|Flood Modeller Tutorial Model]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module01_Provisional| Back to Tutorial Module 01 Main Page]]
}}

FM Tutorial M02 QGIS SHP Pipe Network

2025-09-25T18:01:25Z

Tuflowduncan: /* Conclusion */

<ol>
=Introduction=
This page describes the method for using QGIS to create the GIS based layers representing the pipe network. Two layers will be created each representing the culverts and pits. The pipe network will be connected to the 2D model domain and and a depth-discharge relationship defined at the pits via the creation of a Pit Inlet Database. 

=Method=
<li>Copy the GIS layers '''1d_nwk_FMT_M02_Pipes_001_L.shp''' and '''1d_nwk_FMT_M02_Pits_001_P.shp''' within '''Module_data\Module_02\Pipe_Network''' into the '''TUFLOW\model\gis''' folder.
<li>Open the layer '''1d_nwk_FMT_M02_Pipes_001_L.shp''' in QGIS. This contains polylines representing the culverts that make up the pipe network.
<li>A number of the attributes within the '''1d_nwk_FMT_M02_Pipes_001_L.shp''' layer have not been populated. Turn on Toggle Editing for the layer and add the following attributes to all objects leaving all other attributes unchanged. Make use of the ‘'Update All'’ function as previously explained to update all objects at the same time. 

{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| Type || C
|-
| n_or_n_F || 0.015
|-
| US_Invert || -99999
|-
| DS_Invert || -99999
|-
| Number_of || 1
|}
 
The attributes are described completely in [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-CulvertsAttributeDescriptions Table 5.5] of the TUFLOW Manual. The attributes that we have populated, define: 
*The 1d_nwk type. In this case, we have specified culverts with a circular shape.
*The Manning’s n value of the culvert.
*The upstream invert level of the pipes. When -99,999 is specified, the invert level will be taken from a manually created node or pit at the upstream end of the culvert. Refer to the next steps in this module where these inverts will be defined by creating pits.
*The downstream invert level of the pipes. The same rules as for the upstream invert applies when specifying -99,999.
*The number of identical pipes in parallel. 
 
<li>Open the layer '''1d_nwk_FMT_M02_Pits_001_P.shp''' in QGIS. This contains digitised points that represent the pits of the pipe network through which water can transfer to and from the overlying floodplain.
<li>A number of the attributes within the '''1d_nwk_FMT_M02_Pits_001_P.shp''' layer have not been populated. Toggle Editing for the layer and add the following attributes to all objects leaving all other attributes unchanged. Again, make use of the ‘Update All’ function in QGIS to update all objects at the same time:
 
{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| Type || Q
|-
| Inlet_Type || AB
|-
| Conn_1D_2D || SXL
|}
 
Note that although the same layer (1d_nwk) has been used to define the pits of the pipe network as for the culverts, different attributes have been populated. Refer to
[https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-CulvertsAttributeDescriptions Table 5.5] and [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-PitsModelNetwork Table 5.24] of the TUFLOW Manual for further information on how the attributes of the 1d_nwk layer differ between nodes and channels. The attributes that we have populated for the pits, define: 
*The type of pit channel. In this case, a type ‘Q’ specifies the flow is to be defined by a depth-discharge curve from a user defined database. This database will be created in the next steps of this module.
*AB is the name of the pit inlet type referenced within the pit database.
*Specifying SXL for the ‘Conn_2D’ attribute automatically creates a 2D SX connection at the 2D cell within which the 1D pit is located. In addition, the ZC elevation of the cell will be lowered by the amount specified in the ‘US_Invert’ attribute (0.1m), and the upstream invert of the pit channel set to the lowered 2D cell elevation. This is useful to help trap the water into the pit as it flows overland in the 2D domain. 
 
<li> Open the layer '''1d_x1d_FMT_M01_nwk_001_P.shp''' created in [[Flood_Modeller_Tutorial_Module01_Provisional | Flood Modeller Tutorial 1]]. Note that the pipe network has been digitised to outfall to the watercourse represented within the Flood Modeller Network. We will manually specify the downstream invert levels of Pipe16 and Pipe18 as the discharge point of the pipe network is above the bed level of the watercourse. Use the Info tool and click on each pipe in turn and change the ‘DS_Invert’ attribute for both pipes from -99,999 to 38m.
<li>Save both '''1d_nwk_FMT_M02_Pipes_001_L.shp''' and '''1d_nwk_FMT_M02_Pits_001_P.shp'''. </li> 
'''Pit Inlet Database'''
<li>The Pit Inlet Database has been created and can be found within '''Module_data\Module_02\Pipe_Network'''. Copy the csv files '''pit_inlet_curves.csv''' and '''pit_inlet_dbase.csv''' into a new folder entitled '''pit_dbase''' within the TUFLOW folder.
<li>Open the '''pit_inlet_dbase.csv''' file. The Pit Inlet Database is similar to the Boundary Condition Database in that it references an external source file and relates this to corresponding GIS objects within the model. 
The first column contains the name of pit inlet type as referenced in the Inlet_Type attribute that was specified within the '''1d_nwk_FMT_M02_Pits_001_P.shp''' layer. The second column contains the name of the source .csv file that contains the depth-discharge curve. The third and fourth columns are the heading labels of the depth and discharge columns respectively in the source .csv file. The fifth and sixth columns are the inlet’s nominated full flow area in m2 and flow width in m. [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#DD-Database-3 Section 5.11.3] of the TUFLOW Manual provides further information on the Pit Inlet Database. 
 
[[File:M07 pit inlet dbase.png]] 
 
<li>Open the '''pit_inlet_curves.csv''' file. This contains the depth-discharge curves for each pit inlet type which are referenced within the Pit Inlet Database. The curve for pit inlet type AB will be applied to all pits within this tutorial model. 

[[File:M07 depth discharge.png|800px]]

 {{Video|name= Define Pipe Network Module 02 QGIS SHP.mp4 |width=1123}} 

=Conclusion=
1d_nwk layers have been created representing the culverts and pits that make the pipe network that of the proposed development. The layers have made use of an automated function to link the pits to the 2D domain to allow for the exchange of water between the pipe network and the floodplain. A Pit Inlet Database has been created to define a depth-discharge relationship at each pit. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Define_Boundary_Conditions | Flood Modeller Tutorial 2]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}
</ol>

FM Tutorial M02 QGIS SHP Define Roughness

2025-09-25T18:01:13Z

Tuflowduncan: /* Conclusions */

=Introduction=

This page describes the method for creating the GIS based material types (land use areas) for the proposed development. Once these layers have been setup, surface roughness or bed-resistance values (e.g. Manning’s n) are assigned to each of these land use areas via the materials.csv file present in the model folder.

=Method=
<ol>
<li>Copy the contents of the FMT_tutorial\Module_data\Module_02\Materials into the TUFLOW\model\gis folder. This folder contains the following two layers:
*2d_mat_FMT_M02_DEV_001_R.shp, and
*2d_mat_FMT_M02_DEV_Buildings_001_R.shp .
<li>Open both layers within QGIS. The 2d_mat_FMT_M02_DEV_001_R.shp layer contains polygons defining grassed areas and roads within the proposed development. The 2d_mat_FMT_M02_DEV_Buildings_001_R.shp layer contains polygons defining the buildings within the proposed development.
<li>The materials attribute for a number of polygons representing proposed roads in the 2d_mat_FMT_M02_DEV_001_R.shp layer have not been assigned and will need to be populated. Assign a Material ID of 2 to these polygons as shown in the figure below. Leave the remaining larger polygon with a Material ID of 1. 
<li>All polygons within the 2d_mat_FMT_M02_DEV_Buildings_001_R.shp layer represent the buildings of the proposed development and will have the same Material ID of 3. Make use of the ‘Update All’ feature to automatically assign this value to all objects at the same time. Toggle Editing for the '''2d_mat_FMT_M02_DEV_Buildings_001_R''' layer then right-click and select ''Open Attribute Table''. Type '3' in the blank field and select ''Update All'' as shown in the figure below. 
<li>Open the Materials.csv file within the TUFLOW\model\ folder to observe the Manning’s n values that will be assigned to each Material ID.</ol>

 {{Video|name= Define Surface Roughness Module 02 QGIS SHP.mp4 |width=1123}} 

=Conclusions=

Two 2d_mat GIS layers have been created to define land use categories representing the proposed development. Please return to the main page of the [[Flood_Modeller_Tutorial_Module02_Provisional#Define Pipe Network|Flood Modeller Module 2 Tutorial]]

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

FM Tutorial M02 QGIS SHP Define Elevations

2025-09-25T18:01:05Z

Tuflowduncan: /* Conclusion */

=Introduction=

This page describes the method for using QGIS to create a 3D TIN, modifying the zpt elevations to represent the proposed development. Refer to the [https://docs.tuflow.com/classic-hpc/manual/latest/ TUFLOW Manual] for more information on this feature.

=Method=
<ol>
<li>Copy the contents of the FMT_Tutorial\Module_data\Module_02\2D_Development into the TUFLOW\model\gis folder. This folder contains the following two layers: 
*2d_ztin_FMT_M02_development_001_R.shp, and
*2d_ztin_FMT_M02_development_001_P.shp.

<li>Open the layer '''2d_ztin_ FMT_M02_development_001_R.shp''' within QGIS and observe the polygon and its attributes. This polygon defines the area within which we wish to alter the zpt elevations. Any points falling within the polygon are used for creating the TIN surface. The attributes of this polygon have been left blank (are set to 0) as the elevations will be defined in a separate layer.
<li>Open the layer '''2d_ztin_ FMT_M02_development_001_P.shp''' within QGIS and observe the points and its attributes. These points all have elevations assigned to the ‘Z’ attribute and will be used when generating the TIN. Note that none of the points are snapped to the polygon within the '''2d_ztin_ FMT_M02_development_001_R''' layer. The elevations of the polygon’s perimeter will therefore be based on the current zpt values (i.e. the zpt values assigned by any prior commands). Later on in this tutorial, we will specify the command used within the tgc to associate the two GIS layers with each other. 

 {{Video|name= Define Boundary Conditions Module 02 QGIS SHP.mp4|width=1123}} 

<li> Save and close the layers.</li></ol>

=Conclusion=

The two 2D_tin layers will together modify the zpt elevations in the area of the proposed development. The latter part of this module will demonstrate the command used to write a .tin file to allow for viewing and editing of the TIN directly in SMS. Checks will also be carried out to observe how the TIN has been generated. Please return to the main page of the [[Flood_Modeller_Tutorial_Module02_Provisional#Define Surface Roughness|Flood Modeller Module 2 Tutorial]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

FM Tutorial M02 QGIS SHP Boundary Conditions

2025-09-25T18:00:56Z

Tuflowduncan:

<ol>
=Introduction=
This page details the method for using QGIS to create the GIS based boundary layer. The layer will be populated with the name of each inflow boundary which will be linked to the boundary database in the following steps of this module. The created boundary will be applied as a source-area boundary in a 2d_sa layer. 
=Method=
'''Boundary Condition Database'''
<li>Copy the file '''100yr2hr_loc.csv''' from '''Module_data\Module_02\Inflow''' and place it into the '''TUFLOW\model\bc_dbase''' folder. This file contains the four hydrographs that will be used.
<li>Open up the latest version of the boundary condition database. This is located within the '''TUFLOW\model\bc_dbase folder''' and is called '''bc_dbase_FMT_M01.csv'''.
<li>We need to add four additional rows to the file which reference four additional inflows. The revised bc_dbase should look like the figure below: 
 
[[File:100yr2hr_loc_csv.png]] 
 
The hydrographs applied to each of the 2d_sa polygons are contained within the source file '''100yr2hr_loc.csv'''. 
[[File:100yr2hr loc.PNG|800px]]
 
<li>Save the bc_dbase as '''bc_dbase_FMT_M02.csv'''. It is now ready to be used within the model.
 
<li>Copy the layer '''2d_sa_FMT_M02_001_R.shp''' within the '''Module_data\Module_02\Inflow''' folder into the '''TUFLOW\model\gis''' folder.
<li>Open the layer in QGIS. Four polygons have been digitised over the location of the proposed development. Each polygon represents a sub-catchment to which different inflow boundaries will be associated.
<li>Turn on Toggle Editing mode. Populate the first and only attribute of each polygon with the name of the inflow boundary . The next steps of this module will link these boundary names with an inflow using the bc_dbase located in '''TUFLOW\bc_dbase''' . 
 
[[File:M07 SA polygons QGIS.png|700px]]

 {{Video|name= Define_Boundary_Conditions_Module_02_QGIS_SHP.mp4 |width=1123}} 

 
<li>Save the layer '''2d_sa_FMT_M02_001_R'''. 

=Conclusion=
A GIS layer has been created containing four polygons in a 2d_sa layer over the location of the proposed development. The existing boundary conditions database (bc_dbase) has been modified to link these four GIS objects to hydrographs within an external csv file. Please return to the main page of the [[Flood Modeller Tutorial Module02_Provisional#Flood Modeller 1D/ESTRY 1D Link | Flood Modeller Tutorial 2]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

</ol>

FM Tutorial M02 QGIS SHP Boundary Conditions

2025-09-25T18:00:35Z

Tuflowduncan:

<ol>
=Introduction=
This page details the method for using QGIS to create the GIS based boundary layer. The layer will be populated with the name of each inflow boundary which will be linked to the boundary database in the following steps of this module. The created boundary will be applied as a source-area boundary in a 2d_sa layer. 
=Method=
'''Boundary Condition Database'''
<li>Copy the file '''100yr2hr_loc.csv''' from '''Module_data\Module_02\Inflow''' and place it into the '''TUFLOW\model\bc_dbase''' folder. This file contains the four hydrographs that will be used.
<li>Open up the latest version of the boundary condition database. This is located within the '''TUFLOW\model\bc_dbase folder''' and is called '''bc_dbase_FMT_M01.csv'''.
<li>We need to add four additional rows to the file which reference four additional inflows. The revised bc_dbase should look like the figure below: 
 
[[File:100yr2hr_loc_csv.png]] 
 
The hydrographs applied to each of the 2d_sa polygons are contained within the source file '''100yr2hr_loc.csv'''. 
[[File:100yr2hr loc.PNG|800px]]
 
<li>Save the bc_dbase as '''bc_dbase_FMT_M02.csv'''. It is now ready to be used within the model.
 
<li>Copy the layer '''2d_sa_FMT_M02_001_R.shp''' within the '''Module_data\Module_02\Inflow''' folder into the '''TUFLOW\model\gis''' folder.
<li>Open the layer in QGIS. Four polygons have been digitised over the location of the proposed development. Each polygon represents a sub-catchment to which different inflow boundaries will be associated.
<li>Turn on Toggle Editing mode. Populate the first and only attribute of each polygon with the name of the inflow boundary . The next steps of this module will link these boundary names with an inflow using the bc_dbase located in '''TUFLOW\bc_dbase''' . 
 
[[File:M07 SA polygons QGIS.png|700px]]

 {{Video|name= Define_Boundary_Conditions_Module_02_QGIS_SHP.mp4 |width=1123}} 

 
<li>Save the layer '''2d_sa_FMT_M02_001_R'''. 
 

=Conclusion=
A GIS layer has been created containing four polygons in a 2d_sa layer over the location of the proposed development. The existing boundary conditions database (bc_dbase) has been modified to link these four GIS objects to hydrographs within an external csv file. Please return to the main page of the [[Flood Modeller Tutorial Module02_Provisional#Flood Modeller 1D/ESTRY 1D Link | Flood Modeller Tutorial 2]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}
</ol>

FM Tutorial M02 QGIS GPKG Flood Modeller1D/ESTRY 1D Link

2025-09-25T17:59:30Z

Tuflowduncan: /* Conclusion */

=Introduction=

This page describes the method in QGIS for linking TUFLOW 1D ESTRY networks to a 1D river channel represented within Flood Modeller. Firstly, a pipe network represented in ESTRY will be linked to Flood Modeller using an "X1DH" link. The Flood Modeller 1D network will then be extended downstream by connecting it to an ESTRY river network using an "X1DQ" link.

=Method=
<ol>
<li> Open the layers '''1d_x1d_FMT_M01_nwk_001_P''', '''1d_x1d_FMT_M01_nodes_001_P''', and '''1d_nwk_FMT_M02_Pipes_001_L''' from the '''FMT_M01_002.gpkg''' into QGIS.
<li>Observe that Pipe16 and Pipe18 in the layer '''1d_nwk_FMT_M02_Pipes_001_L''' representing the pipe network have been snapped to node “FC01.11” of the layer '''1d_x1d_FMT_M01_nodes_002_P'''. As an additional node hasn’t been manually added the Flood Modeller-ESTRY link at this location is assumed to be an “X1DH” link. If you open the attribute table you will be able to see that the Conn_1D_2D attribute for “Pipe16” and “Pipe18” has been left blank as an “X1DH” link is used by default and therefore doesn’t need to be specified.
<li>Open the Flood Modeller network (.DAT) file '''FMT_M01_002.dat''' in the Flood Modeller Pro interface. Observe that the updated network file terminates at a stage-time boundary unit named “DSBDY”. This does not need to contain any time-varying data as this data will be overridden by the water levels provided by ESTRY.
<li>Open the layers'''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' within QGIS. These layers are located within the '''Module_data\Module_02\Creek ''' folder.
<li>Drag and drop the GIS layers '''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the three GIS layers in the Layers Panel and reload them from the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>The GIS layer '''1d_nwk_FMT_M02_channels_001_L''' represents the open channel ESTRY network downstream of the Flood Modeller network. A stage-time boundary named "DS_BC" has been set up at the downstream end of the ESTRY network in layer '''1d_bc_FMT_m02_001_P'''.
<li>Observe that an additional node "DSBDY" is present within the updated Read GIS ISIS Nodes layer '''1d_x1d_FMT_M01_nodes_002_P''' at the downstream end of the Flood Modeller network.

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part1.mp4 |width=1123}} 

<li>Open the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS. It is located within the '''Module_data\Module_02\Creek''' folder.
<li>Drag and drop the layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel. Close the layer in the Layers Panel.
<li>Reload the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS from the project GeoPackage file. Turn on Toggle Editing mode and open Field Calculator. Select the field "Source" from the "Update Existing Field" dropdown and enter the expression <nowiki/>'..\\xs\\' ||source to prepend "..\\xs\\" to all rows for this field. The results will be the Source will be set up as per the below image which will ensure that the locations of the csv files are correctly referenced.
</ol>[[File:Source.png|frameless|300x300px]]<ol>
<li>Create a new folder entitled '''xs''' in the '''TUFLOW\model''' folder. Copy the csv files listed below from the '''Module_data\Module_02\Creek''' folder into the newly created '''TUFLOW\model\xs''' folder. These csv files will be used to define the geometry of the river channel cross sections.
*ds_weir.csv
*ds1.csv
*ds2.csv
*ds3.csv
*ds4.csv
*ds5.csv
*ds5_weir.csv
<li>Copy the csv file '''Weir_HT.csv''' from the '''Module_data\Module_02\Creek''' folder to the '''TUFLOW\bc_dbase''' folder. This csv file contains the stage time data that will be applied at the downstream boundary node 'DS_BC'. A constant stage value of 35.5m AOD has been applied .
<li>An additional row needs to be added to '''bc_dbase_FMT_M02.csv''' to apply the stage-time values from '''Weir_HT.csv'''. The revised bc_dbase should look like the figure below:

 
[[File:Bc dbase FMT M01 update.jpg||1200px]] 
 

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part2.mp4 |width=1123}} 

<li>As there is gap between the final node of the Flood Modeller network and the start of the ESTRY network a connector "X" type channel type has been added to connect them. This is present within the '''1d_nwk_FMT_M02_channels_001_L layer.''' This must be digitised from the ESTRY channel (from the first vertex on the polyline) to the Flood Modeller node.
<li>To complete the "X1DQ" link a manually created ESTRY node must be snapped to the Flood Modeller node and have a "Conn_1D_2D" attribute of "X1DQ" specified. To do this, import an empty 1d_nwke_empty_P.gpkg from within the '''FMT_tutorial\FMT_M02\TUFLOW\model\gis\empty''' folder.
<li>Save the empty layer as '''1d_nwke_X1DQ_P''' in the '''TUFLOW\model\gis folder'''. Drag and drop this layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the layer '''1d_nwke_X1DQ_P''' within QGIS and then reload it from the the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>Turn on Toggle Editing for the layer '''1d_nwke_X1DQ_P''' and add the attribute values shown in the table below. Save the layer.
{| class="wikitable" align="center" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;" | Attribute
! style="background-color:#005581; font-weight:bold; color:white;" | Value
|-
| ID || ds2 (remember that Flood Modeller is case sensitive)
|-
| Type || Node
|-
| Conn_1D_2D || X1DQ
|}

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part3.mp4 |width=1123}} 

=Conclusion=

The ESTRY pipe network for the proposed development has been connected via an "X1DH" link to discharge via two pipes into the Flood Modeller network by snapping together the nodes in a 1d_nwk_L layer to a node in the 1d_x1d_P layer. A 1d_nwk_L layer has been added to represent the open channel network downstream of the Flood Modeller network in ESTRY. The cross section data for this open channel network has been defined by adding a 1d_xs_L layer with links to the source csv files at every cross section location. A connector "X" type channel is present and a 1d_nwke_P layer has been added to connect the ESTRY and Flood Modeller open channel networks via an "X1DQ" link. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Modify Simulation Control Files | Flood Modeller Tutorial 2]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

</ol>

FM Tutorial M02 QGIS GPKG Boundary Conditions

2025-09-25T17:59:23Z

Tuflowduncan:

<ol>
=Introduction=
This page details the method for using QGIS to create the GIS based boundary layer. The layer will be populated with the name of each inflow boundary which will be linked to the boundary database in the following steps of this module. The created boundary will be applied as a source-area boundary in a 2d_sa layer. 
=Method=
'''Boundary Condition Database'''
<li>Copy the file '''100yr2hr_loc.csv''' from '''Module_data\Module_02\Inflow''' and place it into the '''TUFLOW\model\bc_dbase''' folder. This file contains the four hydrographs that will be used.
<li>Open up the latest version of the boundary condition database. This is located within the '''TUFLOW\model\bc_dbase folder''' and is called '''bc_dbase_FMT_M01.csv'''.
<li>We need to add four additional rows to the file which reference four additional inflows. The revised bc_dbase should look like the figure below: 
 
[[File:100yr2hr_loc_csv.png]] 
 
The hydrographs applied to each of the 2d_sa polygons are contained within the source file '''100yr2hr_loc.csv'''. 
[[File:100yr2hr loc.PNG|800px]]
 
<li>Save the bc_dbase as '''bc_dbase_FMT_M02.csv'''. It is now ready to be used within the model.
 
<li>Open the layer '''2d_sa_FMT_M02_001_R.shp''' in QGIS. This layer is located within within the '''Module_data\Module_02\Inflow''' folder.
<li>Drag and drop the layer '''2d_sa_FMT_M02_001_R.shp''' into the project GeoPackage file M02_5m_002.gpkg in the Browser Panel.
<li>Close the layer '''2d_sa_FMT_M02_001_R.shp''' in the Layers Panel and reload it from the project GeoPackage file M02_5m_002.gpkg.
<li>The layer '''2d_sa_FMT_M02_001_R''' is made up of four polygons that have been digitised over the location of the proposed development. Each polygon represents a sub-catchment to which different inflow boundaries will be associated.
<li>Turn on Toggle Editing mode. Populate the first and only attribute of each polygon with the name of the inflow boundary . The next steps of this module will link these boundary names with an inflow using the bc_dbase located in '''TUFLOW\bc_dbase''' . 
 
[[File:M07 SA polygons QGIS.png|700px]]

 {{Video|name= Define Boundary Conditions Module 02 QGIS GPKG.mp4 |width=1123}} 
<li>Save the layer '''2d_sa_FMT_M02_001_R'''. 

=Conclusion=
A GIS layer has been created containing four polygons in a 2d_sa layer over the location of the proposed development. The existing boundary conditions database (bc_dbase) has been modified to link these four GIS objects to hydrographs within an external csv file. Please return to the main page of the [[Flood Modeller Tutorial Module02_Provisional#Flood Modeller 1D/ESTRY 1D Link | Flood Modeller Tutorial 2]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

</ol>

FM Tutorial M02 QGIS GPKG Boundary Conditions

2025-09-25T17:59:04Z

Tuflowduncan: /* Conclusion */

<ol>
=Introduction=
This page details the method for using QGIS to create the GIS based boundary layer. The layer will be populated with the name of each inflow boundary which will be linked to the boundary database in the following steps of this module. The created boundary will be applied as a source-area boundary in a 2d_sa layer. 
=Method=
'''Boundary Condition Database'''
<li>Copy the file '''100yr2hr_loc.csv''' from '''Module_data\Module_02\Inflow''' and place it into the '''TUFLOW\model\bc_dbase''' folder. This file contains the four hydrographs that will be used.
<li>Open up the latest version of the boundary condition database. This is located within the '''TUFLOW\model\bc_dbase folder''' and is called '''bc_dbase_FMT_M01.csv'''.
<li>We need to add four additional rows to the file which reference four additional inflows. The revised bc_dbase should look like the figure below: 
 
[[File:100yr2hr_loc_csv.png]] 
 
The hydrographs applied to each of the 2d_sa polygons are contained within the source file '''100yr2hr_loc.csv'''. 
[[File:100yr2hr loc.PNG|800px]]
 
<li>Save the bc_dbase as '''bc_dbase_FMT_M02.csv'''. It is now ready to be used within the model.
 
<li>Open the layer '''2d_sa_FMT_M02_001_R.shp''' in QGIS. This layer is located within within the '''Module_data\Module_02\Inflow''' folder.
<li>Drag and drop the layer '''2d_sa_FMT_M02_001_R.shp''' into the project GeoPackage file M02_5m_002.gpkg in the Browser Panel.
<li>Close the layer '''2d_sa_FMT_M02_001_R.shp''' in the Layers Panel and reload it from the project GeoPackage file M02_5m_002.gpkg.
<li>The layer '''2d_sa_FMT_M02_001_R''' is made up of four polygons that have been digitised over the location of the proposed development. Each polygon represents a sub-catchment to which different inflow boundaries will be associated.
<li>Turn on Toggle Editing mode. Populate the first and only attribute of each polygon with the name of the inflow boundary . The next steps of this module will link these boundary names with an inflow using the bc_dbase located in '''TUFLOW\bc_dbase''' . 
 
[[File:M07 SA polygons QGIS.png|700px]]

 {{Video|name= Define Boundary Conditions Module 02 QGIS GPKG.mp4 |width=1123}} 

 
<li>Save the layer '''2d_sa_FMT_M02_001_R'''. 
 

=Conclusion=
A GIS layer has been created containing four polygons in a 2d_sa layer over the location of the proposed development. The existing boundary conditions database (bc_dbase) has been modified to link these four GIS objects to hydrographs within an external csv file. Please return to the main page of the [[Flood Modeller Tutorial Module02_Provisional#Flood Modeller 1D/ESTRY 1D Link | Flood Modeller Tutorial 2]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

</ol>

FM Tutorial M02 QGIS GPKG Pipe Network

2025-09-25T17:58:57Z

Tuflowduncan: /* Conclusion */

<ol>
=Introduction=
This page describes the method for using QGIS to create the GIS based layers representing the pipe network. Two layers will be created each representing the culverts and pits. The pipe network will be connected to the 2D model domain and and a depth-discharge relationship defined at the pits via the creation of a Pit Inlet Database. 

=Method=
<li>Open the GIS layers '''1d_nwk_FMT_M02_Pipes_001_L.shp''' and '''1d_nwk_FMT_M02_Pits_001_P.shp''' in QGIS. These layers are located within the '''Module_data\Module_02\Pipe_Network''' into the '''TUFLOW\model\gis''' folder.
<li>Drag and drop the two layers into the project GeoPackage file M02_5m_002.gpkg in the Browser Panel.
<li>Close the two layers in the Layers Panel and reload them from the project GeoPackage file M02_5m_002.gpkg.
<li>The layer '''1d_nwk_FMT_M02_Pipes_001_L''' consist of polylines representing the culverts that make up the pipe network.
<li>A number of the attributes within the '''1d_nwk_FMT_M02_Pipes_001_L''' layer have not been populated. Turn on Toggle Editing for the layer and add the following attributes to all objects leaving all other attributes unchanged. Make use of the ‘'Update All'’ function as previously explained to update all objects at the same time. 

{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| Type || C
|-
| n_or_n_F || 0.015
|-
| US_Invert || -99999
|-
| DS_Invert || -99999
|-
| Number_of || 1
|}
 
The attributes are described completely in [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-CulvertsAttributeDescriptions Table 5.5] of the TUFLOW Manual. The attributes that we have populated, define: 
*The 1d_nwk type. In this case, we have specified culverts with a circular shape.
*The Manning’s n value of the culvert.
*The upstream invert level of the pipes. When -99,999 is specified, the invert level will be taken from a manually created node or pit at the upstream end of the culvert. Refer to the next steps in this module where these inverts will be defined by creating pits.
*The downstream invert level of the pipes. The same rules as for the upstream invert applies when specifying -99,999.
*The number of identical pipes in parallel. 
<li>The layer '''1d_nwk_FMT_M02_Pits_001_P''' contains digitised points that represent the pits of the pipe network through which water can transfer to and from the overlying floodplain.
<li>A number of the attributes within the '''1d_nwk_FMT_M02_Pits_001_P''' layer have not been populated. Toggle Editing for the layer and add the following attributes to all objects leaving all other attributes unchanged. Again, make use of the ‘Update All’ function in QGIS to update all objects at the same time:
 
{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| Type || Q
|-
| Inlet_Type || AB
|-
| Conn_1D_2D || SXL
|}
 
Note that although the same layer (1d_nwk) has been used to define the pits of the pipe network as for the culverts, different attributes have been populated. Refer to
[https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-CulvertsAttributeDescriptions Table 5.5] and [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-PitsModelNetwork Table 5.24] of the TUFLOW Manual for further information on how the attributes of the 1d_nwk layer differ between nodes and channels. The attributes that we have populated for the pits, define: 
*The type of pit channel. In this case, a type ‘Q’ specifies the flow is to be defined by a depth-discharge curve from a user defined database. This database will be created in the next steps of this module.
*AB is the name of the pit inlet type referenced within the pit database.
*Specifying SXL for the ‘Conn_2D’ attribute automatically creates a 2D SX connection at the 2D cell within which the 1D pit is located. In addition, the ZC elevation of the cell will be lowered by the amount specified in the ‘US_Invert’ attribute (0.1m), and the upstream invert of the pit channel set to the lowered 2D cell elevation. This is useful to help trap the water into the pit as it flows overland in the 2D domain. 
 
<li> Open the layer '''1d_x1d_FMT_M01_nwk_001_P''' created in [[Flood_Modeller_Tutorial_Module01_Provisional | Flood Modeller Tutorial 1]]. Note that the pipe network has been digitised to outfall to the watercourse represented within the Flood Modeller Network. We will manually specify the downstream invert levels of Pipe16 and Pipe18 as the discharge point of the pipe network is above the bed level of the watercourse. Use the Info tool and click on each pipe in turn and change the ‘DS_Invert’ attribute for both pipes from -99,999 to 38m.
<li>Save both '''1d_nwk_FMT_M02_Pipes_001_L''' and '''1d_nwk_FMT_M02_Pits_001_P'''. </ol>'''Pit Inlet Database'''<ol>
<li>The Pit Inlet Database has been created and can be found within '''Module_data\Module_02\Pipe_Network'''. Copy the csv files '''pit_inlet_curves.csv''' and '''pit_inlet_dbase.csv'''’ into a new folder entitled '''pit_dbase''' within the TUFLOW folder.
<li>Open the '''pit_inlet_dbase.csv''' file. The Pit Inlet Database is similar to the Boundary Condition Database in that it references an external source file and relates this to corresponding GIS objects within the model. 
The first column contains the name of pit inlet type as referenced in the Inlet_Type attribute that was specified within the '''1d_nwk_FMT_M02_Pits_001_P.shp''' layer. The second column contains the name of the source .csv file that contains the depth-discharge curve. The third and fourth columns are the heading labels of the depth and discharge columns respectively in the source .csv file. The fifth and sixth columns are the inlet’s nominated full flow area in m2 and flow width in m. [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#DD-Database-3 Section 5.11.3] of the TUFLOW Manual provides further information on the Pit Inlet Database. 
 
[[File:M07 pit inlet dbase.png]] 
 
<li>Open the '''pit_inlet_curves.csv''' file. This contains the depth-discharge curves for each pit inlet type which are referenced within the Pit Inlet Database. The curve for pit inlet type AB will be applied to all pits within this tutorial model. 

[[File:M07 depth discharge.png|800px]]

 {{Video|name= Define Pipe Network Module 02 QGIS GPKG.mp4 |width=1123}} 

=Conclusion=
1d_nwk layers have been created representing the culverts and pits that make the pipe network that of the proposed development. The layers have made use of an automated function to link the pits to the 2D domain to allow for the exchange of water between the pipe network and the floodplain. A Pit Inlet Database has been created to define a depth-discharge relationship at each pit. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Define_Boundary_Conditions | Flood Modeller Tutorial 2]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}
</ol>

FM Tutorial M02 QGIS GPKG Define Roughness

2025-09-25T17:58:46Z

Tuflowduncan: /* Conclusions */

=Introduction=

This page describes the method for creating the GIS based material types (land use areas) for the proposed development. Once these layers have been setup, surface roughness or bed-resistance values (e.g. Manning’s n) are assigned to each of these land use areas via the materials.csv file present in the model folder.

=Method=
<ol>
<li>Open the contents of the FMT_tutorial\Module_data\Module_02\Materials folder in QGIS. This folder contains the following two layers:
*2d_mat_FMT_M02_DEV_001_R.shp, and
*2d_mat_FMT_M02_DEV_Buildings_001_R.shp .
<li>Move the layers 2d_mat_FMT_M02_DEV_001_R.shp and 2d_mat_FMT_M02_DEV_Buildings_001_R.shp into the project GeoPackage file M02_5m_002.gpkg.
<li>Close the two layers in the Layers Panel and then reload them from the project GeoPackage file '''M02_5m_002.gpkg'''.

<li> The 2d_mat_FMT_M02_DEV_001_R layer contains polygons defining grassed areas and roads within the proposed development. The materials attribute for a number of polygons representing proposed roads in the 2d_mat_FMT_M02_DEV_001_R layer have not been assigned and will need to be populated. Turn on Toggle Editing mode and assign a Material ID of 2 to these polygons as shown in the figure below. Leave the remaining larger polygon with a Material ID of 1. 
<li>The 2d_mat_FMT_M02_DEV_Buildings_001_R layer contains polygons defining the buildings within the proposed development.All polygons within the 2d_mat_FMT_M02_DEV_Buildings_001_R layer represent the buildings of the proposed development and will have the same Material ID of 3. Make use of the ‘Update All’ feature to automatically assign this value to all objects at the same time. Toggle Editing for the '''2d_mat_FMT_M02_DEV_Buildings_001_R''' layer then right-click and select ''Open Attribute Table''. Type '3' in the blank field and select ''Update All'' as shown in the figure below. 
<li>Open the Materials.csv file within the TUFLOW\model\ folder to observe the Manning’s n values that will be assigned to each Material ID.</ol>

 {{Video|name= Define Surface Roughness Module 02 QGIS GPKG.mp4 |width=1123}} 

=Conclusions=

Two 2d_mat GIS layers have been created to define land use categories representing the proposed development. Please return to the main page of the [[Flood_Modeller_Tutorial_Module02_Provisional#Define Pipe Network|Flood Modeller Module 2 Tutorial]]

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

FM Tutorial M02 QGIS GPKG Define Elevations

2025-09-25T17:58:36Z

Tuflowduncan: /* Conclusion */

=Introduction=

This page describes the method for using QGIS to create a 3D TIN, modifying the zpt elevations to represent the proposed development. Refer to the [https://docs.tuflow.com/classic-hpc/manual/latest/ TUFLOW Manual] for more information on this feature.

=Method=
<ol>
<li>Open the contents of the FMT_Tutorial\Module_data\Module_02\2D_Development folder in QGIS. This folder contains the following two layers: 
*2d_ztin_FMT_M02_development_001_R.shp, and
*2d_ztin_FMT_M02_development_001_P.shp
<li>Move the layers '''2d_ztin_ FMT_M02_development_001_R.shp''' and '''2d_ztin_ FMT_M02_development_001_P.shp''' into the project GeoPackage file '''M02_5m_002.gpkg''' in the Browser Panel.
<li>Close the two layers in the Layers Panel and then reload them from the project GeoPackage file '''M02_5m_002.gpkg'''.
<li>The '''2d_ztin_ FMT_M02_development_001_R''' layer consists of a polygon which defines the area within which we wish to alter the zpt elevations. Any points falling within the polygon are used for creating the TIN surface. The attributes of this polygon have been left blank (are set to 0) as the elevations will be defined in a separate layer.
<li>Open the attribute table for the layer '''2d_ztin_ FMT_M02_development_001_P'''. All of the points have elevations assigned to the ‘Z’ attribute and will be used when generating the TIN. Note that none of the points are snapped to the polygon within the '''2d_ztin_ FMT_M02_development_001_R''' layer. The elevations of the polygon’s perimeter will therefore be based on the current zpt values (i.e. the zpt values assigned by any prior commands). Later on in this tutorial, we will specify the command used within the tgc to associate the two GIS layers with each other. 

 {{Video|name= Define Elevations Module 02 QGIS GPKG.mp4 |width=1123}} 

<li> Save and close the layers.</li></ol>

=Conclusion=

The two 2D_tin layers will together modify the zpt elevations in the area of the proposed development. The latter part of this module will demonstrate the command used to write a .tin file to allow for viewing and editing of the TIN directly in SMS. Checks will also be carried out to observe how the TIN has been generated. Please return to the main page of the [[Flood_Modeller_Tutorial_Module02_Provisional#Define Surface Roughness|Flood Modeller Module 2 Tutorial]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 02 Main Page]]
}}

FM Tutorial M02 QGIS GPKG Define Elevations

2025-09-25T17:58:28Z

Tuflowduncan: /* Conclusion */

=Introduction=

This page describes the method for using QGIS to create a 3D TIN, modifying the zpt elevations to represent the proposed development. Refer to the [https://docs.tuflow.com/classic-hpc/manual/latest/ TUFLOW Manual] for more information on this feature.

=Method=
<ol>
<li>Open the contents of the FMT_Tutorial\Module_data\Module_02\2D_Development folder in QGIS. This folder contains the following two layers: 
*2d_ztin_FMT_M02_development_001_R.shp, and
*2d_ztin_FMT_M02_development_001_P.shp
<li>Move the layers '''2d_ztin_ FMT_M02_development_001_R.shp''' and '''2d_ztin_ FMT_M02_development_001_P.shp''' into the project GeoPackage file '''M02_5m_002.gpkg''' in the Browser Panel.
<li>Close the two layers in the Layers Panel and then reload them from the project GeoPackage file '''M02_5m_002.gpkg'''.
<li>The '''2d_ztin_ FMT_M02_development_001_R''' layer consists of a polygon which defines the area within which we wish to alter the zpt elevations. Any points falling within the polygon are used for creating the TIN surface. The attributes of this polygon have been left blank (are set to 0) as the elevations will be defined in a separate layer.
<li>Open the attribute table for the layer '''2d_ztin_ FMT_M02_development_001_P'''. All of the points have elevations assigned to the ‘Z’ attribute and will be used when generating the TIN. Note that none of the points are snapped to the polygon within the '''2d_ztin_ FMT_M02_development_001_R''' layer. The elevations of the polygon’s perimeter will therefore be based on the current zpt values (i.e. the zpt values assigned by any prior commands). Later on in this tutorial, we will specify the command used within the tgc to associate the two GIS layers with each other. 

 {{Video|name= Define Elevations Module 02 QGIS GPKG.mp4 |width=1123}} 

<li> Save and close the layers.</li></ol>

=Conclusion=

The two 2D_tin layers will together modify the zpt elevations in the area of the proposed development. The latter part of this module will demonstrate the command used to write a .tin file to allow for viewing and editing of the TIN directly in SMS. Checks will also be carried out to observe how the TIN has been generated. Please return to the main page of the [[Flood_Modeller_Tutorial_Module02_Provisional#Define Surface Roughness|Flood Modeller Module 2 Tutorial]].

{{Tips Navigation
|uplink=[[Flood_Modeller_Tutorial_Module02_Provisional| Back to Tutorial Module 03 Main Page]]
}}

FM Tutorial M02 QGIS GPKG Flood Modeller1D/ESTRY 1D Link

2025-09-25T17:56:35Z

Tuflowduncan: /* Method */

=Introduction=

This page describes the method in QGIS for linking TUFLOW 1D ESTRY networks to a 1D river channel represented within Flood Modeller. Firstly, a pipe network represented in ESTRY will be linked to Flood Modeller using an "X1DH" link. The Flood Modeller 1D network will then be extended downstream by connecting it to an ESTRY river network using an "X1DQ" link.

=Method=
<ol>
<li> Open the layers '''1d_x1d_FMT_M01_nwk_001_P''', '''1d_x1d_FMT_M01_nodes_001_P''', and '''1d_nwk_FMT_M02_Pipes_001_L''' from the '''FMT_M01_002.gpkg''' into QGIS.
<li>Observe that Pipe16 and Pipe18 in the layer '''1d_nwk_FMT_M02_Pipes_001_L''' representing the pipe network have been snapped to node “FC01.11” of the layer '''1d_x1d_FMT_M01_nodes_002_P'''. As an additional node hasn’t been manually added the Flood Modeller-ESTRY link at this location is assumed to be an “X1DH” link. If you open the attribute table you will be able to see that the Conn_1D_2D attribute for “Pipe16” and “Pipe18” has been left blank as an “X1DH” link is used by default and therefore doesn’t need to be specified.
<li>Open the Flood Modeller network (.DAT) file '''FMT_M01_002.dat''' in the Flood Modeller Pro interface. Observe that the updated network file terminates at a stage-time boundary unit named “DSBDY”. This does not need to contain any time-varying data as this data will be overridden by the water levels provided by ESTRY.
<li>Open the layers'''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' within QGIS. These layers are located within the '''Module_data\Module_02\Creek ''' folder.
<li>Drag and drop the GIS layers '''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the three GIS layers in the Layers Panel and reload them from the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>The GIS layer '''1d_nwk_FMT_M02_channels_001_L''' represents the open channel ESTRY network downstream of the Flood Modeller network. A stage-time boundary named "DS_BC" has been set up at the downstream end of the ESTRY network in layer '''1d_bc_FMT_m02_001_P'''.
<li>Observe that an additional node "DSBDY" is present within the updated Read GIS ISIS Nodes layer '''1d_x1d_FMT_M01_nodes_002_P''' at the downstream end of the Flood Modeller network.

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part1.mp4 |width=1123}} 

<li>Open the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS. It is located within the '''Module_data\Module_02\Creek''' folder.
<li>Drag and drop the layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel. Close the layer in the Layers Panel.
<li>Reload the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS from the project GeoPackage file. Turn on Toggle Editing mode and open Field Calculator. Select the field "Source" from the "Update Existing Field" dropdown and enter the expression <nowiki/>'..\\xs\\' ||source to prepend "..\\xs\\" to all rows for this field. The results will be the Source will be set up as per the below image which will ensure that the locations of the csv files are correctly referenced.
</ol>[[File:Source.png|frameless|300x300px]]<ol>
<li>Create a new folder entitled '''xs''' in the '''TUFLOW\model''' folder. Copy the csv files listed below from the '''Module_data\Module_02\Creek''' folder into the newly created '''TUFLOW\model\xs''' folder. These csv files will be used to define the geometry of the river channel cross sections.
*ds_weir.csv
*ds1.csv
*ds2.csv
*ds3.csv
*ds4.csv
*ds5.csv
*ds5_weir.csv
<li>Copy the csv file '''Weir_HT.csv''' from the '''Module_data\Module_02\Creek''' folder to the '''TUFLOW\bc_dbase''' folder. This csv file contains the stage time data that will be applied at the downstream boundary node 'DS_BC'. A constant stage value of 35.5m AOD has been applied .
<li>An additional row needs to be added to '''bc_dbase_FMT_M02.csv''' to apply the stage-time values from '''Weir_HT.csv'''. The revised bc_dbase should look like the figure below:

 
[[File:Bc dbase FMT M01 update.jpg||1200px]] 
 

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part2.mp4 |width=1123}} 

<li>As there is gap between the final node of the Flood Modeller network and the start of the ESTRY network a connector "X" type channel type has been added to connect them. This is present within the '''1d_nwk_FMT_M02_channels_001_L layer.''' This must be digitised from the ESTRY channel (from the first vertex on the polyline) to the Flood Modeller node.
<li>To complete the "X1DQ" link a manually created ESTRY node must be snapped to the Flood Modeller node and have a "Conn_1D_2D" attribute of "X1DQ" specified. To do this, import an empty 1d_nwke_empty_P.gpkg from within the '''FMT_tutorial\FMT_M02\TUFLOW\model\gis\empty''' folder.
<li>Save the empty layer as '''1d_nwke_X1DQ_P''' in the '''TUFLOW\model\gis folder'''. Drag and drop this layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the layer '''1d_nwke_X1DQ_P''' within QGIS and then reload it from the the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>Turn on Toggle Editing for the layer '''1d_nwke_X1DQ_P''' and add the attribute values shown in the table below. Save the layer.
{| class="wikitable" align="center" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;" | Attribute
! style="background-color:#005581; font-weight:bold; color:white;" | Value
|-
| ID || ds2 (remember that Flood Modeller is case sensitive)
|-
| Type || Node
|-
| Conn_1D_2D || X1DQ
|}

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part3.mp4 |width=1123}} 

=Conclusion=

The ESTRY pipe network for the proposed development has been connected via an "X1DH" link to discharge via two pipes into the Flood Modeller network by snapping together the nodes in a 1d_nwk_L layer to a node in the 1d_x1d_P layer. A 1d_nwk_L layer has been added to represent the open channel network downstream of the Flood Modeller network in ESTRY. The cross section data for this open channel network has been defined by adding a 1d_xs_L layer with links to the source csv files at every cross section location. A connector "X" type channel is present and a 1d_nwke_P layer has been added to connect the ESTRY and Flood Modeller open channel networks via an "X1DQ" link. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Modify Simulation Control Files | Flood Modeller Tutorial 2]].

</ol>

FM Tutorial M02 QGIS GPKG Flood Modeller1D/ESTRY 1D Link

2025-09-25T17:54:07Z

Tuflowduncan: /* Method */

=Introduction=

This page describes the method in QGIS for linking TUFLOW 1D ESTRY networks to a 1D river channel represented within Flood Modeller. Firstly, a pipe network represented in ESTRY will be linked to Flood Modeller using an "X1DH" link. The Flood Modeller 1D network will then be extended downstream by connecting it to an ESTRY river network using an "X1DQ" link.

=Method=
<ol>
<li> Open the layers '''1d_x1d_FMT_M01_nwk_001_P''', '''1d_x1d_FMT_M01_nodes_001_P''', and '''1d_nwk_FMT_M02_Pipes_001_L''' from the '''FMT_M01_002.gpkg''' into QGIS.
<li>Observe that Pipe16 and Pipe18 in the layer '''1d_nwk_FMT_M02_Pipes_001_L''' representing the pipe network have been snapped to node “FC01.11” of the layer '''1d_x1d_FMT_M01_nodes_002_P'''. As an additional node hasn’t been manually added the Flood Modeller-ESTRY link at this location is assumed to be an “X1DH” link. If you open the attribute table you will be able to see that the Conn_1D_2D attribute for “Pipe16” and “Pipe18” has been left blank as an “X1DH” link is used by default and therefore doesn’t need to be specified.
<li>Open the Flood Modeller network (.DAT) file '''FMT_M01_002.dat''' in the Flood Modeller Pro interface. Observe that the updated network file terminates at a stage-time boundary unit named “DSBDY”. This does not need to contain any time-varying data as this data will be overridden by the water levels provided by ESTRY.
<li>Open the layers'''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' within QGIS. These layers are located within the '''Module_data\Module_02\Creek ''' folder.
<li>Drag and drop the GIS layers '''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the three GIS layers in the Layers Panel and reload them from the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>The GIS layer '''1d_nwk_FMT_M02_channels_001_L''' represents the open channel ESTRY network downstream of the Flood Modeller network. A stage-time boundary named "DS_BC" has been set up at the downstream end of the ESTRY network in layer '''1d_bc_FMT_m02_001_P'''.
<li>Observe that an additional node "DSBDY" is present within the updated Read GIS ISIS Nodes layer '''1d_x1d_FMT_M01_nodes_002_P''' at the downstream end of the Flood Modeller network.

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part1.mp4 |width=1123}} 

<li>Open the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS. It is located within the '''Module_data\Module_02\Creek''' folder.
<li>Drag and drop the layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel. Close the layer in the Layers Panel.
<li>Reload the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS from the project GeoPackage file. Turn on Toggle Editing mode and open Field Calculator. Select the field "Source" from the "Update Existing Field" dropdown and enter the expression <nowiki/>'..\\xs\\' ||source to prepend "..\\xs\\" to all rows for this field. The results will be the Source will be set up as per the below image which will ensure that the locations of the csv files are correctly referenced.
</ol>[[File:Source.png|frameless|300x300px]]<ol>
<li>Create a new folder entitled '''xs''' in the '''TUFLOW\model''' folder. Copy the csv files listed below from the '''Module_data\Module_02\Creek''' folder into the newly created '''TUFLOW\model\xs''' folder. These csv files will be used to define the geometry of the river channel cross sections.
*ds_weir.csv
*ds1.csv
*ds2.csv
*ds3.csv
*ds4.csv
*ds5.csv
*ds5_weir.csv
<li>Copy the csv file '''Weir_HT.csv''' from the '''Module_data\Module_02\Creek''' folder to the '''TUFLOW\bc_dbase''' folder. This csv file contains the stage time data that will be applied at the downstream boundary node 'DS_BC'. A constant stage value of 35.5m AOD has been applied .
<li>An additional row needs to be added to '''bc_dbase_FMT_M02.csv''' to apply the stage-time values from '''Weir_HT.csv'''. The revised bc_dbase should look like the figure below:

 
[[File:Bc dbase FMT M01 update.jpg||1200px]] 
 

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part2.mp4 |width=1123}} 

<li>As there is gap between the final node of the Flood Modeller network and the start of the ESTRY network a connector "X" type channel type has been added to connect them. This must be digitised from the ESTRY channel (from the first vertex on the polyline) to the Flood Modeller node.
<li>To complete the "X1DQ" link a manually created ESTRY node must be snapped to the Flood Modeller node and have a "Conn_1D_2D" attribute of "X1DQ" specified. To do this, import an empty 1d_nwke_empty_P.gpkg from within the FMT_tutorial\FMT_M02\TUFLOW\model\gis\empty folder.
<li>Save the empty layer as '''1d_nwke_X1DQ_P''' in the '''TUFLOW\model\gis folder'''. Drag and drop this layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the layer '''1d_nwke_X1DQ_P''' within QGIS and then reload it from the the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>Turn on Toggle Editing for the layer '''1d_nwke_X1DQ_P''' and add the attribute values shown in the table below. Save the layer.
{| class="wikitable" align="center" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;" | Attribute
! style="background-color:#005581; font-weight:bold; color:white;" | Value
|-
| ID || ds2 (remember that Flood Modeller is case sensitive)
|-
| Type || Node
|-
| Conn_1D_2D || X1DQ
|}

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part3.mp4 |width=1123}} 

=Conclusion=

The ESTRY pipe network for the proposed development has been connected via an "X1DH" link to discharge via two pipes into the Flood Modeller network by snapping together the nodes in a 1d_nwk_L layer to a node in the 1d_x1d_P layer. A 1d_nwk_L layer has been added to represent the open channel network downstream of the Flood Modeller network in ESTRY. The cross section data for this open channel network has been defined by adding a 1d_xs_L layer with links to the source csv files at every cross section location. A connector "X" type channel and a 1d_nwke_P layer have been added to connect the ESTRY and Flood Modeller open channel networks via an "X1DQ" link. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Modify Simulation Control Files | Flood Modeller Tutorial 2]].

</ol>

FM Tutorial M02 QGIS GPKG Flood Modeller1D/ESTRY 1D Link

2025-09-25T14:12:38Z

Tuflowduncan: /* Method */

=Introduction=

This page describes the method in QGIS for linking TUFLOW 1D ESTRY networks to a 1D river channel represented within Flood Modeller. Firstly, a pipe network represented in ESTRY will be linked to Flood Modeller using an "X1DH" link. The Flood Modeller 1D network will then be extended downstream by connecting it to an ESTRY river network using an "X1DQ" link.

=Method=
<ol>
<li> Open the layers '''1d_x1d_FMT_M01_nwk_001_P''', '''1d_x1d_FMT_M01_nodes_001_P''', and '''1d_nwk_FMT_M02_Pipes_001_L''' from the '''FMT_M01_002.gpkg''' into QGIS.
<li>Observe that Pipe16 and Pipe18 in the layer '''1d_nwk_FMT_M02_Pipes_001_L''' representing the pipe network have been snapped to node “FC01.11” of the layer '''1d_x1d_FMT_M01_nodes_002_P'''. As an additional node hasn’t been manually added the Flood Modeller-ESTRY link at this location is assumed to be an “X1DH” link. If you open the attribute table you will be able to see that the Conn_1D_2D attribute for “Pipe16” and “Pipe18” has been left blank as an “X1DH” link is used by default and therefore doesn’t need to be specified.
<li>Open the Flood Modeller network (.DAT) file '''FMT_M01_002.dat''' in the Flood Modeller Pro interface. Observe that the updated network file terminates at a stage-time boundary unit named “DSBDY”. This does not need to contain any time-varying data as this data will be overridden by the water levels provided by ESTRY.
<li>Open the layers'''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' within QGIS. These layers are located within the '''Module_data\Module_02\Creek ''' folder.
<li>Drag and drop the GIS layers '''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the three GIS layers in the Layers Panel and reload them from the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>The GIS layer '''1d_nwk_FMT_M02_channels_001_L''' represents the open channel ESTRY network downstream of the Flood Modeller network. A stage-time boundary named "DS_BC" has been set up at the downstream end of the ESTRY network in layer '''1d_bc_FMT_m02_001_P'''.
<li>Observe that an additional node "DSBDY" is present within the updated Read GIS ISIS Nodes layer '''1d_x1d_FMT_M01_nodes_002_P''' at the downstream end of the Flood Modeller network.

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part1.mp4 |width=1123}} 

<li>Open the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS. It is located within the '''Module_data\Module_02\Creek''' folder.
<li>Drag and drop the layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel. Close the layer in the Layers Panel.
<li>Reload the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS from the project GeoPackage file. Turn on Toggle Editing mode and open Field Calculator. Select the field "Source" from the "Update Existing Field" dropdown and enter the expression <nowiki/>'..\\xs\\' ||source to prepend "..\\xs\\" to all rows for this field. The results will be the Source will be set up as per the below image which will ensure that the locations of the csv files are correctly referenced.
</ol>[[File:Source.png|frameless|300x300px]]<ol>
<li>Create a new folder entitled '''xs''' in the '''TUFLOW\model''' folder. Copy the csv files listed below from the '''Module_data\Module_02\Creek''' folder into the newly created '''TUFLOW\model\xs''' folder. These csv files will be used to define the geometry of the river channel cross sections.
*ds_weir.csv
*ds1.csv
*ds2.csv
*ds3.csv
*ds4.csv
*ds5.csv
*ds5_weir.csv
<li>Copy the csv file '''Weir_HT.csv''' from the '''Module_data\Module_02\Creek''' folder to the '''TUFLOW\bc_dbase''' folder. This csv file contains the stage time data that will be applied at the downstream boundary node 'DS_BC'. A constant stage value of 35.5m AOD has been applied .
<li>An additional row needs to be added to '''bc_dbase_FMT_M02.csv''' to apply the stage-time values from '''Weir_HT.csv'''. The revised bc_dbase should look like the figure below:

 
[[File:Bc dbase FMT M01 update.jpg||1200px]] 
 

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part2.mp4 |width=1123}} 

<li>As there is gap between the final node of the Flood Modeller network and the start of the ESTRY network a connector "X" type channel type has been added to connect them. This must be digitised from the ESTRY channel (from the first vertex on the polyline) to the Flood Modeller node.
<li>To complete the "X1DQ" link a manually created ESTRY node must be snapped to the Flood Modeller node and have a "Conn_1D_2D" attribute of "X1DQ" specified. To do this, import an empty 1d_nwke_empty_P.gpkg from within the FMT_tutorial\FMT_M02\TUFLOW\model\gis\empty folder.
<li>Save the empty layer as '''1d_nwke_X1DQ_P''' in the '''TUFLOW\model\gis folder'''. Drag and drop this layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the layer '''1d_nwke_X1DQ_P''' within QGIS and then reload it from the the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>Turn on Toggle Editing for the layer '''1d_nwke_X1DQ_P''' and add the attribute values shown in the table below. Save the layer.
{| class="wikitable" align="center" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;" | Attribute
! style="background-color:#005581; font-weight:bold; color:white;" | Value
|-
| ID || DS2
|-
| Type || Node
|-
| Conn_1D_2D || X1DQ
|}

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part3.mp4 |width=1123}} 

=Conclusion=

The ESTRY pipe network for the proposed development has been connected via an "X1DH" link to discharge via two pipes into the Flood Modeller network by snapping together the nodes in a 1d_nwk_L layer to a node in the 1d_x1d_P layer. A 1d_nwk_L layer has been added to represent the open channel network downstream of the Flood Modeller network in ESTRY. The cross section data for this open channel network has been defined by adding a 1d_xs_L layer with links to the source csv files at every cross section location. A connector "X" type channel and a 1d_nwke_P layer have been added to connect the ESTRY and Flood Modeller open channel networks via an "X1DQ" link. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Modify Simulation Control Files | Flood Modeller Tutorial 2]].

</ol>

FM Tutorial M02 QGIS GPKG Flood Modeller1D/ESTRY 1D Link

2025-09-25T14:04:46Z

Tuflowduncan: /* Method */

=Introduction=

This page describes the method in QGIS for linking TUFLOW 1D ESTRY networks to a 1D river channel represented within Flood Modeller. Firstly, a pipe network represented in ESTRY will be linked to Flood Modeller using an "X1DH" link. The Flood Modeller 1D network will then be extended downstream by connecting it to an ESTRY river network using an "X1DQ" link.

=Method=
<ol>
<li> Open the layers '''1d_x1d_FMT_M01_nwk_001_P''', '''1d_x1d_FMT_M01_nodes_001_P''', and '''1d_nwk_FMT_M02_Pipes_001_L''' from the '''FMT_M01_002.gpkg''' into QGIS.
<li>Observe that Pipe16 and Pipe18 in the layer '''1d_nwk_FMT_M02_Pipes_001_L''' representing the pipe network have been snapped to node “FC01.11” of the layer '''1d_x1d_FMT_M01_nodes_002_P'''. As an additional node hasn’t been manually added the Flood Modeller-ESTRY link at this location is assumed to be an “X1DH” link. If you open the attribute table you will be able to see that the Conn_1D_2D attribute for “Pipe16” and “Pipe18” has been left blank as an “X1DH” link is used by default and therefore doesn’t need to be specified.
<li>Open the Flood Modeller network (.DAT) file '''FMT_M01_002.dat''' in the Flood Modeller Pro interface. Observe that the updated network file terminates at a stage-time boundary unit named “DSBDY”. This does not need to contain any time-varying data as this data will be overridden by the water levels provided by ESTRY.
<li>Open the layers'''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' within QGIS. These layers are located within the '''Module_data\Module_02\Creek ''' folder.
<li>Drag and drop the GIS layers '''1d_x1d_FMT_M01_nodes_002_P.shp''', '''1d_bc_FMT_m02_001_P.shp''', and '''1d_nwk_FMT_M02_channels_001_L.shp''' into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the three GIS layers in the Layers Panel and reload them from the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>The GIS layer '''1d_nwk_FMT_M02_channels_001_L''' represents the open channel ESTRY network downstream of the Flood Modeller network. A stage-time boundary named "DS_BC" has been set up at the downstream end of the ESTRY network in layer '''1d_bc_FMT_m02_001_P'''.
<li>Observe that an additional node "DSBDY" is present within the updated Read GIS ISIS Nodes layer '''1d_x1d_FMT_M01_nodes_002_P''' at the downstream end of the Flood Modeller network.

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part1.mp4 |width=1123}} 

<li>Open the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS. It is located within the '''Module_data\Module_02\Creek''' folder.
<li>Drag and drop the layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel. Close the layer in the Layers Panel.
<li>Reload the layer '''1d_xs_FMT_M02_creek_001_L''' within QGIS from the project GeoPackage file. Turn on Toggle Editing mode and open Field Calculator. Select the field "Source" from the "Update Existing Field" dropdown and enter the expression <nowiki/>'..\\xs\\' ||source to prepend "..\\xs\\" to all rows for this field. The results will be the Source will be set up as per the below image which will ensure that the locations of the csv files are correctly referenced.
</ol>[[File:Source.png|frameless|300x300px]]<ol>
<li>Create a new folder entitled '''xs''' in the '''TUFLOW\model''' folder. Copy the csv files listed below from the '''Module_data\Module_02\Creek''' folder into the newly created '''TUFLOW\model\xs''' folder. These csv files will be used to define the geometry of the river channel cross sections.
*ds_weir.csv
*ds1.csv
*ds2.csv
*ds3.csv
*ds4.csv
*ds5.csv
*ds5_weir.csv
<li>Copy the csv file '''Weir_HT.csv''' from the '''Module_data\Module_02\Creek''' folder to the '''TUFLOW\bc_dbase''' folder. This csv file contains the stage time data that will be applied at the downstream boundary node 'DS_BC'. A constant stage value of 35.5m AOD has been applied .
<li>An additional row needs to be added to '''bc_dbase_FMT_M01.csv''' to apply the stage-time values from '''Weir_HT.csv'''. The revised bc_dbase should look like the figure below:

 
[[File:Bc dbase FMT M01 update.jpg||1200px]] 
 

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part2.mp4 |width=1123}} 

<li>As there is gap between the final node of the Flood Modeller network and the start of the ESTRY network a connector "X" type channel type has been added to connect them. This must be digitised from the ESTRY channel (from the first vertex on the polyline) to the Flood Modeller node.
<li>To complete the "X1DQ" link a manually created ESTRY node must be snapped to the Flood Modeller node and have a "Conn_1D_2D" attribute of "X1DQ" specified. To do this, import an empty 1d_nwke_empty_P.gpkg from within the FMT_tutorial\FMT_M02\TUFLOW\model\gis\empty folder.
<li>Save the empty layer as '''1d_nwke_X1DQ_P''' in the '''TUFLOW\model\gis folder'''. Drag and drop this layer into the project GeoPackage file '''FMT_M01_002.gpkg''' in the Browser Panel.
<li>Close the layer '''1d_nwke_X1DQ_P''' within QGIS and then reload it from the the project GeoPackage file '''FMT_M01_002.gpkg'''.
<li>Turn on Toggle Editing for the layer '''1d_nwke_X1DQ_P''' and add the attribute values shown in the table below. Save the layer.
{| class="wikitable" align="center" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;" | Attribute
! style="background-color:#005581; font-weight:bold; color:white;" | Value
|-
| ID || DS2
|-
| Type || Node
|-
| Conn_1D_2D || X1DQ
|}

 {{Video|name= FMP ESTRY 1D Link Module 02 QGIS GPKG Part3.mp4 |width=1123}} 

=Conclusion=

The ESTRY pipe network for the proposed development has been connected via an "X1DH" link to discharge via two pipes into the Flood Modeller network by snapping together the nodes in a 1d_nwk_L layer to a node in the 1d_x1d_P layer. A 1d_nwk_L layer has been added to represent the open channel network downstream of the Flood Modeller network in ESTRY. The cross section data for this open channel network has been defined by adding a 1d_xs_L layer with links to the source csv files at every cross section location. A connector "X" type channel and a 1d_nwke_P layer have been added to connect the ESTRY and Flood Modeller open channel networks via an "X1DQ" link. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Modify Simulation Control Files | Flood Modeller Tutorial 2]].

</ol>

File:Source.png

2025-09-25T14:03:54Z

Tuflowduncan:

1d_XS_FMT_M02_Creek_001_L

FM Tutorial M02 QGIS GPKG Pipe Network

2025-09-25T11:15:12Z

Tuflowduncan:

<ol>
=Introduction=
This page describes the method for using QGIS to create the GIS based layers representing the pipe network. Two layers will be created each representing the culverts and pits. The pipe network will be connected to the 2D model domain and and a depth-discharge relationship defined at the pits via the creation of a Pit Inlet Database. 

=Method=
<li>Open the GIS layers '''1d_nwk_FMT_M02_Pipes_001_L.shp''' and '''1d_nwk_FMT_M02_Pits_001_P.shp''' in QGIS. These layers are located within the '''Module_data\Module_02\Pipe_Network''' into the '''TUFLOW\model\gis''' folder.
<li>Drag and drop the two layers into the project GeoPackage file M02_5m_002.gpkg in the Browser Panel.
<li>Close the two layers in the Layers Panel and reload them from the project GeoPackage file M02_5m_002.gpkg.
<li>The layer '''1d_nwk_FMT_M02_Pipes_001_L''' consist of polylines representing the culverts that make up the pipe network.
<li>A number of the attributes within the '''1d_nwk_FMT_M02_Pipes_001_L''' layer have not been populated. Turn on Toggle Editing for the layer and add the following attributes to all objects leaving all other attributes unchanged. Make use of the ‘'Update All'’ function as previously explained to update all objects at the same time. 

{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| Type || C
|-
| n_or_n_F || 0.015
|-
| US_Invert || -99999
|-
| DS_Invert || -99999
|-
| Number_of || 1
|}
 
The attributes are described completely in [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-CulvertsAttributeDescriptions Table 5.5] of the TUFLOW Manual. The attributes that we have populated, define: 
*The 1d_nwk type. In this case, we have specified culverts with a circular shape.
*The Manning’s n value of the culvert.
*The upstream invert level of the pipes. When -99,999 is specified, the invert level will be taken from a manually created node or pit at the upstream end of the culvert. Refer to the next steps in this module where these inverts will be defined by creating pits.
*The downstream invert level of the pipes. The same rules as for the upstream invert applies when specifying -99,999.
*The number of identical pipes in parallel. 
<li>The layer '''1d_nwk_FMT_M02_Pits_001_P''' contains digitised points that represent the pits of the pipe network through which water can transfer to and from the overlying floodplain.
<li>A number of the attributes within the '''1d_nwk_FMT_M02_Pits_001_P''' layer have not been populated. Toggle Editing for the layer and add the following attributes to all objects leaving all other attributes unchanged. Again, make use of the ‘Update All’ function in QGIS to update all objects at the same time:
 
{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| Type || Q
|-
| Inlet_Type || AB
|-
| Conn_1D_2D || SXL
|}
 
Note that although the same layer (1d_nwk) has been used to define the pits of the pipe network as for the culverts, different attributes have been populated. Refer to
[https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-CulvertsAttributeDescriptions Table 5.5] and [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-PitsModelNetwork Table 5.24] of the TUFLOW Manual for further information on how the attributes of the 1d_nwk layer differ between nodes and channels. The attributes that we have populated for the pits, define: 
*The type of pit channel. In this case, a type ‘Q’ specifies the flow is to be defined by a depth-discharge curve from a user defined database. This database will be created in the next steps of this module.
*AB is the name of the pit inlet type referenced within the pit database.
*Specifying SXL for the ‘Conn_2D’ attribute automatically creates a 2D SX connection at the 2D cell within which the 1D pit is located. In addition, the ZC elevation of the cell will be lowered by the amount specified in the ‘US_Invert’ attribute (0.1m), and the upstream invert of the pit channel set to the lowered 2D cell elevation. This is useful to help trap the water into the pit as it flows overland in the 2D domain. 
 
<li> Open the layer '''1d_x1d_FMT_M01_nwk_001_P''' created in [[Flood_Modeller_Tutorial_Module01_Provisional | Flood Modeller Tutorial 1]]. Note that the pipe network has been digitised to outfall to the watercourse represented within the Flood Modeller Network. We will manually specify the downstream invert levels of Pipe16 and Pipe18 as the discharge point of the pipe network is above the bed level of the watercourse. Use the Info tool and click on each pipe in turn and change the ‘DS_Invert’ attribute for both pipes from -99,999 to 38m.
<li>Save both '''1d_nwk_FMT_M02_Pipes_001_L''' and '''1d_nwk_FMT_M02_Pits_001_P'''. </ol>'''Pit Inlet Database'''<ol>
<li>The Pit Inlet Database has been created and can be found within '''Module_data\Module_02\Pipe_Network'''. Copy the csv files '''pit_inlet_curves.csv''' and '''pit_inlet_dbase.csv'''’ into a new folder entitled '''pit_dbase''' within the TUFLOW folder.
<li>Open the '''pit_inlet_dbase.csv''' file. The Pit Inlet Database is similar to the Boundary Condition Database in that it references an external source file and relates this to corresponding GIS objects within the model. 
The first column contains the name of pit inlet type as referenced in the Inlet_Type attribute that was specified within the '''1d_nwk_FMT_M02_Pits_001_P.shp''' layer. The second column contains the name of the source .csv file that contains the depth-discharge curve. The third and fourth columns are the heading labels of the depth and discharge columns respectively in the source .csv file. The fifth and sixth columns are the inlet’s nominated full flow area in m2 and flow width in m. [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#DD-Database-3 Section 5.11.3] of the TUFLOW Manual provides further information on the Pit Inlet Database. 
 
[[File:M07 pit inlet dbase.png]] 
 
<li>Open the '''pit_inlet_curves.csv''' file. This contains the depth-discharge curves for each pit inlet type which are referenced within the Pit Inlet Database. The curve for pit inlet type AB will be applied to all pits within this tutorial model. 

[[File:M07 depth discharge.png|800px]]

 {{Video|name= Define Pipe Network Module 02 QGIS GPKG.mp4 |width=1123}} 

=Conclusion=
1d_nwk layers have been created representing the culverts and pits that make the pipe network that of the proposed development. The layers have made use of an automated function to link the pits to the 2D domain to allow for the exchange of water between the pipe network and the floodplain. A Pit Inlet Database has been created to define a depth-discharge relationship at each pit. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Define_Boundary_Conditions | Flood Modeller Tutorial 2]].

</ol>

FM Tutorial M02 QGIS GPKG Pipe Network

2025-09-25T11:13:50Z

Tuflowduncan:

<ol>
=Introduction=
This page describes the method for using QGIS to create the GIS based layers representing the pipe network. Two layers will be created each representing the culverts and pits. The pipe network will be connected to the 2D model domain and and a depth-discharge relationship defined at the pits via the creation of a Pit Inlet Database. 

=Method=
<li>Open the GIS layers '''1d_nwk_FMT_M02_Pipes_001_L.shp''' and '''1d_nwk_FMT_M02_Pits_001_P.shp''' in QGIS. These layers are located within the '''Module_data\Module_02\Pipe_Network''' into the '''TUFLOW\model\gis''' folder.
<li>Drag and drop the two layers into the project GeoPackage file M02_5m_002.gpkg in the Browser Panel.
<li>Close the two layers in the Layers Panel and reload them from the project GeoPackage file M02_5m_002.gpkg.
<li>The layer '''1d_nwk_FMT_M02_Pipes_001_L''' consist of polylines representing the culverts that make up the pipe network.
<li>A number of the attributes within the '''1d_nwk_FMT_M02_Pipes_001_L''' layer have not been populated. Turn on Toggle Editing for the layer and add the following attributes to all objects leaving all other attributes unchanged. Make use of the ‘'Update All'’ function as previously explained to update all objects at the same time. 

{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| Type || C
|-
| n_or_n_F || 0.015
|-
| US_Invert || -99999
|-
| DS_Invert || -99999
|-
| Number_of || 1
|}
 
The attributes are described completely in [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-CulvertsAttributeDescriptions Table 5.5] of the TUFLOW Manual. The attributes that we have populated, define: 
*The 1d_nwk type. In this case, we have specified culverts with a circular shape.
*The Manning’s n value of the culvert.
*The upstream invert level of the pipes. When -99,999 is specified, the invert level will be taken from a manually created node or pit at the upstream end of the culvert. Refer to the next steps in this module where these inverts will be defined by creating pits.
*The downstream invert level of the pipes. The same rules as for the upstream invert applies when specifying -99,999.
*The number of identical pipes in parallel. 
<li>The layer '''1d_nwk_FMT_M02_Pits_001_P''' contains digitised points that represent the pits of the pipe network through which water can transfer to and from the overlying floodplain.
<li>A number of the attributes within the '''1d_nwk_FMT_M02_Pits_001_P''' layer have not been populated. Toggle Editing for the layer and add the following attributes to all objects leaving all other attributes unchanged. Again, make use of the ‘Update All’ function in QGIS to update all objects at the same time:
 
{| align="center" class="wikitable" width="25%"

! style="background-color:#005581; font-weight:bold; color:white;"| Attribute
! style="background-color:#005581; font-weight:bold; color:white;"| Value
|-
| Type || Q
|-
| Inlet_Type || AB
|-
| Conn_1D_2D || SXL
|}
 
Note that although the same layer (1d_nwk) has been used to define the pits of the pipe network as for the culverts, different attributes have been populated. Refer to
[https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-CulvertsAttributeDescriptions Table 5.5] and [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#tab:tab-PitsModelNetwork Table 5.24] of the TUFLOW Manual for further information on how the attributes of the 1d_nwk layer differ between nodes and channels. The attributes that we have populated for the pits, define: 
*The type of pit channel. In this case, a type ‘Q’ specifies the flow is to be defined by a depth-discharge curve from a user defined database. This database will be created in the next steps of this module.
*AB is the name of the pit inlet type referenced within the pit database.
*Specifying SXL for the ‘Conn_2D’ attribute automatically creates a 2D SX connection at the 2D cell within which the 1D pit is located. In addition, the ZC elevation of the cell will be lowered by the amount specified in the ‘US_Invert’ attribute (0.1m), and the upstream invert of the pit channel set to the lowered 2D cell elevation. This is useful to help trap the water into the pit as it flows overland in the 2D domain. 
 
<li> Open the layer '''1d_x1d_FMT_M01_nwk_001_P''' created in [[Flood_Modeller_Tutorial_Module01_Provisional | Flood Modeller Tutorial 1]]. Note that the pipe network has been digitised to outfall to the watercourse represented within the Flood Modeller Network. We will manually specify the downstream invert levels of Pipe16 and Pipe18 as the discharge point of the pipe network is above the bed level of the watercourse. Use the Info tool and click on each pipe in turn and change the ‘DS_Invert’ attribute for both pipes from -99,999 to 38m.
<li>Save both '''1d_nwk_FMT_M02_Pipes_001_L''' and '''1d_nwk_FMT_M02_Pits_001_P'''. 
'''Pit Inlet Database'''
<li>The Pit Inlet Database has been created and can be found within '''Module_data\Module_02\Pipe_Network'''. Copy the csv files '''pit_inlet_curves.csv''' and '''pit_inlet_dbase.csv'''’ into a new folder entitled '''pit_dbase''' within the TUFLOW folder.
<li>Open the '''pit_inlet_dbase.csv''' file. The Pit Inlet Database is similar to the Boundary Condition Database in that it references an external source file and relates this to corresponding GIS objects within the model. 
The first column contains the name of pit inlet type as referenced in the Inlet_Type attribute that was specified within the '''1d_nwk_FMT_M02_Pits_001_P.shp''' layer. The second column contains the name of the source .csv file that contains the depth-discharge curve. The third and fourth columns are the heading labels of the depth and discharge columns respectively in the source .csv file. The fifth and sixth columns are the inlet’s nominated full flow area in m2 and flow width in m. [https://docs.tuflow.com/classic-hpc/manual/2025.1/OneD-Domains-1.html#DD-Database-3 Section 5.11.3] of the TUFLOW Manual provides further information on the Pit Inlet Database. 
 
[[File:M07 pit inlet dbase.png]] 
 
<li>Open the '''pit_inlet_curves.csv''' file. This contains the depth-discharge curves for each pit inlet type which are referenced within the Pit Inlet Database. The curve for pit inlet type AB will be applied to all pits within this tutorial model. 

[[File:M07 depth discharge.png|800px]]

 {{Video|name= Define Pipe Network Module 02 QGIS GPKG.mp4 |width=1123}} 

=Conclusion=
1d_nwk layers have been created representing the culverts and pits that make the pipe network that of the proposed development. The layers have made use of an automated function to link the pits to the 2D domain to allow for the exchange of water between the pipe network and the floodplain. A Pit Inlet Database has been created to define a depth-discharge relationship at each pit. Please return to the main page of the[[Flood Modeller Tutorial Module02_Provisional#Define_Boundary_Conditions | Flood Modeller Tutorial 2]].

</ol>

FM Tutorial M02 QGIS GPKG Define Roughness

2025-09-25T11:03:56Z

Tuflowduncan: /* Method */

=Introduction=

This page describes the method for creating the GIS based material types (land use areas) for the proposed development. Once these layers have been setup, surface roughness or bed-resistance values (e.g. Manning’s n) are assigned to each of these land use areas via the materials.csv file present in the model folder.

=Method=
<ol>
<li>Open the contents of the FMT_tutorial\Module_data\Module_02\Materials folder in QGIS. This folder contains the following two layers:
*2d_mat_FMT_M02_DEV_001_R.shp, and
*2d_mat_FMT_M02_DEV_Buildings_001_R.shp .
<li>Move the layers 2d_mat_FMT_M02_DEV_001_R.shp and 2d_mat_FMT_M02_DEV_Buildings_001_R.shp into the project GeoPackage file M02_5m_002.gpkg.
<li>Close the two layers in the Layers Panel and then reload them from the project GeoPackage file '''M02_5m_002.gpkg'''.

<li> The 2d_mat_FMT_M02_DEV_001_R layer contains polygons defining grassed areas and roads within the proposed development. The materials attribute for a number of polygons representing proposed roads in the 2d_mat_FMT_M02_DEV_001_R layer have not been assigned and will need to be populated. Turn on Toggle Editing mode and assign a Material ID of 2 to these polygons as shown in the figure below. Leave the remaining larger polygon with a Material ID of 1. 
<li>The 2d_mat_FMT_M02_DEV_Buildings_001_R layer contains polygons defining the buildings within the proposed development.All polygons within the 2d_mat_FMT_M02_DEV_Buildings_001_R layer represent the buildings of the proposed development and will have the same Material ID of 3. Make use of the ‘Update All’ feature to automatically assign this value to all objects at the same time. Toggle Editing for the '''2d_mat_FMT_M02_DEV_Buildings_001_R''' layer then right-click and select ''Open Attribute Table''. Type '3' in the blank field and select ''Update All'' as shown in the figure below. 
<li>Open the Materials.csv file within the TUFLOW\model\ folder to observe the Manning’s n values that will be assigned to each Material ID.</ol>

 {{Video|name= Define Surface Roughness Module 02 QGIS GPKG.mp4 |width=1123}} 

=Conclusions=

Two 2d_mat GIS layers have been created to define land use categories representing the proposed development. Please return to the main page of the [[Flood_Modeller_Tutorial_Module02_Provisional#Define Pipe Network|Flood Modeller Module 2 Tutorial]]

File:Ief tcf.png

2025-09-25T09:35:23Z

Tuflowduncan:

IEF Links Tab