# SMS:SRH-2D Files

The available input and output files for SRH-2D are listed below.

SMS Input Files
Name Description
DB3 dBASE III SRH-2D Information
H5 2D Scatter XMDF Information
MAP Mesh Arcs Information
MATERIALS Materials Types Information
PRJ Projection
Pre-SRH Input Files
Name Description
SRHGEOM Mesh Geometry
SRHHYDRO Model Control
SRHMAT Mesh Material
SRHSEDMAT Sediment Material Properties
SRHMPOINT Monitor Points
XYS Input files for XY Series of data including:
• BC Flow time series
• BC Stage vs. Flow rating curve
• BC Sediment vs. Flow rating curve
SRH-2D Input Files
Name Description
DAT Pre-SRH File
SOF.DAT Pre-SRH Script Output File
SRH-2D Output Files
Name Description
DIA.dat Diagnostic Grid Depth Values XMDF
DIP.dat Dynamic Input Telescoping Grid
INF.dat Courant–Friedrichs–Lewy Residuals
EXITn.dat Q and WSE Time step Averages
LNn.dat Monitor Line Report
OUT.dat Model Run Summary Output
PTn.dat Monitor Point Report
PTnSED.dat Monitor Points Report for Sediment Transport Simulations
RCn.dat Rating Curve Report
HYn.dat HY-8 Culvert Report
CULVn.dat FST Culvert Report
WEIRn.dat 1D Weir Report
GATEn.dat 1D Gate Report
INTERNALn.dat Pressure Flow Structure Overtopping Report
RES.dat Time step Residuals
RSTn.dat Restart (Hotstart) Result Output
TSO.dat Time step Series Output Index
INF.dat Global Information
XMDF.H5 Output WSE, Depth, Velocity, etc.

An explanation of files used by and generated by SRH-2D are as follows:

## Output Files

A description of each file generated during an SRH-2D simulation run is as follows. In the file descriptions, * is a placeholder representing the specific case name as specified in the model control:

*.DAT
File created when SRHpre is run, for use by SRH-2D. It contains model input information as well as geometry information about the mesh.
*_DIA.dat
Diagnostic file with potential errors and warnings about the execution. It helps to identify causes of execution error or failure. For the tutorial case, the file is almost empty indicating a successful run of the model.
*_DIP.dat
Dynamic Input file allows setting up or modify frequently used parameters during an SRH-2D execution. Parameters that can be set up or modified include the total simulation time, number of iterations within each time step, specification of restart files, time interval used for writing out intermediate results, time step interval, damping, relaxation for continuity and momentum equations, and the turbulence model type. Changing the parameters in this file is not usually recommended. See SRH-2D documentation for more information about the implementation of this file.
*_LNn.dat
Monitor line file where flow discharge and water surface elevation are recorded corresponding to time. For sediment transport simulations, sediment discharge, concentration, bed elevations, and size fraction sediment discharges are added to this file.
*_OUT.dat
Output file providing general model information such as input parameters, mesh size, list of restart file numbers and their corresponding time, cpu time of the simulation, etc.
*_PTn.dat
Monitor point file that provides time history of output hydraulic variables at the user-specified monitor points. For sediment transport runs the D50 bed material size is also output. The file is in column format and may be imported into Excel for plotting. Output from the file may be used to decide if a steady state solution has been obtained or to examine unsteady change of a variable. If additional monitor points are used, files would have a similar naming convention with the only change being PT1, PT2, PT3, etc.
*_PTnSED.dat
This file is similar to the *_PTn.dat file that provides time history of output sediment transport variables at the user-specified monitor points.
*_RCn.dat
If a rating curve has been specified for the exit boundary condition this file is generated. It contains columns reporting the water surface elevation and flow rates at the exit boundary condition throughout the simulation run. If multiple exit boundary conditions have rating curves specified, a series of these files would be created having a similar naming convention with the only change being RC1, RC2, RC3, etc.
*_HYn.dat
If an HY-8 culvert is part of the simulation, then this file is generated. It reports data columns of computed flow rates, headwater, and tailwater throughout the simulation run. If multiple HY-8 culverts are included in the simulation, a series of these files would be created having a similar naming convention with the only change being HY1, HY2, HY3, etc.
*_CULVn.dat
If an FST culvert is part of the simulation, then this file is generated. It reports data columns of computed flow rates, headwater, tailwater, invert elevation, whether it is overtopped, and whether it is inlet controlled throughout the simulation run. If multiple FST culverts are included in the simulation, a series of these files would be created having a similar naming convention with the only change being CULV1, CULV2, CULV3, etc.
*_WEIRn.dat
If a 1D weir is part of the simulation, then this file is generated. It reports data columns of computed flow rates, crest elevation, upstream water surface elevation, and downstream water surface elevation throughout the simulation run. If multiple 1D weirs are included in the simulation, a series of these files would be created having a similar naming convention with the only change being WEIR1, WEIR2, WEIR3, etc.
*_GATEn.dat
If a 1D gate is part of the simulation, then this file is generated. It reports data columns of computed flow rates, crest elevation, upstream water surface elevation, and downstream water surface elevation throughout the simulation run. If multiple 1D gates are included in the simulation, a series of these files would be created having a similar naming convention with the only change being GATE1, GATE2, GATE3, etc.
*_INTERNALn.dat
If overtopping has been specified for any pressure flow structures in the simulation this file is generated. It contains columns reporting the water surface elevation and overtopping flow rates throughout the simulation run. If multiple pressure flow structures have overtopping specified, a series of these files would be created having a similar naming convention with the only change being INTERNAL1, INTERNAL2, INTERNAL3, etc.
*_RES.dat
Residual file that contains residuals of continuity and two velocity equations during the solution. Note that residuals are normalized. For example, the ResH is normalized by the maximum of the first three iterations. Therefore, residual of 1.0 is obtained for ResH if NITER is less than 4 in the c1_DIP.dat file.
*_RSTn.dat
Restart file used as a model input in successive runs. These are written out at an interval specified within the model control. If there is a restart file, there is an option to start a model run using it as the initial conditions of the model. Multiple restart files are generated during the model run. When the solution is loaded into SMS, only the final restart file will be saved and the intermediate files will be deleted. If wanting an intermediate RST file, copy it from the directory before loading the solution.
*_SOF.dat
Script Output File generated when SRHpre is run. In the script output file all inputs are saved. Can be used to rerun SRHpre by changing the name to *_SIF.dat
*_TSO.dat
The time series output index file which contains a list which matches the restart file to a specific time step.
*_INF.dat
Global informational file including the global residual for water surface elevations (RES_H), as well as the residuals for the X and Y velocity components (RES_U and RES_V). It also includes other global information such as the number of wet cells and the net flowrate at the exit boundaries. These are all reported to this file once every 100 timesteps.
*_XMDF.h5
Output Extensible Model Data Format (XMDF) file used by SMS for post-processing and visualization of results. Results include water surface elevation, water depth, depth averaged velocity, Froude number, and bed shear stress. If a model includes sediment transport, output results also include bed elevation, sediment concentration, bed material D50 particle size, and erosion and deposition amounts.

## Native Files

SRH-2D makes use of native files. The four native files are *.SRHHYDRO, *.SRMAT, *.SRHSEDMAT, *.SRHMPOINT, and *.SRHGEOM as described below:

### SRHHYDRO File

SRHHYDRO is written out by SMS to guide SRH-2D through the hydraulic simulation. The SRHHYDRO file contains key information about the simulation while acting as a directory to other files for SRH-2D to use. The SRHHYDRO file stores the case name, simulation description, model type, turbulence model information, Manning’s n values, boundary conditions, boundary types, unsteady flow designation, simulation time, resultant output information, and initial conditions. Details of each card in the file are given as follows:

 Case This is an identifier for SRH-2D to use when running to help recognize the files that correspond to a specific project. The case should be given a name that is unique for a simulation. Description The description is to show in review of what was done for a specific simulation RunType This card tells SRH-2D what to compute. Flow means a hydraulic model. Mobile refers to a sediment transport model. ModelTemp This card communicates to SRH-2D whether the model will be used to simulate temperature. Currently, temperature is not supported by SRH-2D v. 2.2 UnsteadyOutput Unsteady output is labeled for unsteady, where intermediate calculations are performed, or as steady, where only final calculations are computed for accuracy. SimTime Three numbers are given to specify start time (hours), time step (seconds), and total simulation time (hours). TurbulenceModel This option is either parabolic or ke for the current version of SRH-2D. ParabolicTurbulence This card is dependent on TurbulenceModel being labeled parabolic. The value is a constant used in the parabolic turbulence equation. InitCondOption This card communicates to SRH-2D the condition of each element prior the model run. Options include dry, auto, and rst, where rst represents a start-up file from a previous run. Grid This card tells SRH-2D the name of the grid file. HydroMat This card tells SRH-2D the name of the material file. SubsurfaceBedFile This card tells SRH-2D the name of the sediment material file. MonitorPtFile This card tells SRH-2D the name of the monitor point file if one has been created. OutputFormat This option represents how SMS will write out the final files to be read back for post processing. Two inputs are required, the file type and the resultant units. OutputInterval This card tells SRH-2D how often to write out results during the simulation. The value is given in hours. ManningsN In this location two values are given representing the material number and the value of Manning’s n corresponding to that material value. SMS will always write a zero material type as a default. NumSubsurfaceLayers This card indicates the number of sediment layers for each sediment material type. (SRH-2D requires that at least 2 layers be specified, even if they are teh same materials.) Subsurface Thickness This card indicates the thicknesses and bulk unit weights of sediment layers. BedSedComposition This line points to the files (.xys) containing the sediment gradations for each sediment layer. BC This card refers to the boundary type. Two values are given representing the boundary number and the type of boundary for each boundary number IQParams This card will be written for boundary types that ask for a subcritical inlet boundary. The values given represent the boundary id, the constant flow value or variable flow file name, the units of flow, and the distribution type ISupCrParams This card requires the same information as IQParams with the addition of constant water surface elevation or varable water surface elevation file name. EWSParams This card represents the stage exit boundary. Values include the boundary id, the constant watersurface elevation or variable watersurface elevation file, and units type. EQParams This card gives the constant discharge value or variable discharge file name and unit type. NDParams This card refers to a normal depth outlet boundary. Values include the nodestring number at which flow will be computed as well as the average bed slope at the exit location.

The file acts as a map guiding SRH-2D to other important files such as the SRHMAT file, the SRHMONITORPTS file, and the SRHGEOM file.

#### SRHHYDRO Example

```SRHHYDRO 30
Case "Case"
Description "Description"
RunType FLOW
ModelTemp OFF
SimTime 0 1 3
TurbulenceModel PARABOLIC
ParabolicTurbulence 0.7
InitCondOption DRY
Grid "HohRiv.srhgeom"
HydroMat "HohRiv.srhmat"
MonitorPtFile "HohRiv.srhmpoint"
OutputFormat XMDF ENGLISH
OutputInterval 1
ManningsN 0 0.02
ManningsN 1 0.025
ManningsN 2 0.07
BC 6 WALL
BC 5 WALL
BC 4 MONITORING
BC 3 MONITORING
BC 2 EXIT-H
BC 1 INLET-Q
IQParams 1 "HohRiv.srhcurve1.xys" EN  CONVEYANCE
EWSParams 2 "HohRiv.srhcurve2.xys" EN
```

### SRHMAT File

The SRHMAT file gives each element a material type. This file will categorize each element to a Manning’s n value.

#### SRHMAT Example

```SRHMAT 30
NMaterials 3
MatName 1 "Channel"
MatName 2 "Forest"
Material 1 1 2 12 14 15 23 24 26 27 28
29 36 37 38 39 40 41 42 49 50
51 52 53 54 55 56 63 64 65 66
67 68 69 70 71 82 83 84 85 86
87 88 89 90 91 103 104 106 107 108
109 110 111 112 113 114 115 116 117 118
119 120 121 132 133 134 135 136 137 138
139 140 141 142 143 144 145 146 147 148
149 150 151 152 153 154 155 156 157 158
159 170 171 172 173 174 175 176 177 178
179 180 181 182 183 184 185 186 187 188
189 190 191 192 193 194 195 196 207 208
209 210 211 212 213 214 215 216 217 218

Material 2 3 4 5 6 7 8 9 10 11 13
16 17 18 19 20 21 22 25 30 31
32 33 34 35 43 44 45 46 47 48
57 58 59 60 61 62 72 73 74 75
76 77 78 79 80 81 92 93 94 95
96 97 98 99 100 101 102 105 122 123
124 125 126 127 128 129 130 131 160 161
162 163 164 165 166 167 168 169 197 198
199 200 201 202 203 204 205 206 228 229
237 238 239 240 241 242 243 244 245 246
```

### SRHSEDMAT File

The SRHSEDMAT file gives each element a sediment material type. This file will categorize each element with specific sediment layer thicknesses, bulk densities, and gradations. The sediment materials may be the same or differ from the material types.

#### SRHSEDMAT Example

```SRHSEDMAT 30
NSedMaterials 3
SedMatName 1 "Channel"
SedMatName 2 "Forest"
SedMaterial 1 1 2 12 14 15 23 24 26 27 28
29 36 37 38 39 40 41 42 49 50
51 52 53 54 55 56 63 64 65 66
67 68 69 70 71 82 83 84 85 86
87 88 89 90 91 103 104 106 107 108
109 110 111 112 113 114 115 116 117 118
119 120 121 132 133 134 135 136 137 138
139 140 141 142 143 144 145 146 147 148
149 150 151 152 153 154 155 156 157 158
159 170 171 172 173 174 175 176 177 178
179 180 181 182 183 184 185 186 187 188
189 190 191 192 193 194 195 196 207 208
209 210 211 212 213 214 215 216 217 218
SedMaterial 2 3 4 5 6 7 8 9 10 11 13
16 17 18 19 20 21 22 25 30 31
32 33 34 35 43 44 45 46 47 48
57 58 59 60 61 62 72 73 74 75
76 77 78 79 80 81 92 93 94 95
96 97 98 99 100 101 102 105 122 123
124 125 126 127 128 129 130 131 160 161
162 163 164 165 166 167 168 169 197 198
199 200 201 202 203 204 205 206 228 229
237 238 239 240 241 242 243 244 245 246
```

### SRHMPOINT File

The SRHMONITORPTS file or SRHMPOINT file is tells SRH-2D that there are monitor points to watch and where those points are located. SRH-2D will take the coordinates from SMS to locate the areas to be monitored.

#### SRHMPOINT Example

```SRHMON 30
NUMMONITORPTS 2
monitorpt 1 798814 309513
monitorpt 2 799387 305853
```

### SRHGEOM File

The SRHGEOM file tells SRH-2D where each node is located and which nodes comprise each element. The SRHGEOM file also holds information about the units of the grid and node strings that are used for boundary conditions and monitor lines.

#### SRHGEOM Example

```SRHGEOM 30
Name "HohRiverDomain"

GridUnit "FOOT"

Elem 1 5 1 6 15
Elem 2 1 2 7 6
Elem 3 3 1 5
Elem 4 2 1 3
Elem 5 5 8 3
Elem 6 3 8 10
Elem 7 9 8 4
Elem 8 13 4 14
Elem 9 14 4 8
Elem 10 11 4 13
Elem 11 4 11 9
Elem 12 14 5 15 24
Elem 13 8 5 14
Elem 14 6 7 17 16
Node 1 798908 309671 169.545
Node 2 798857 309733 170.299
Node 3 798975 309744 171.463
Node 4 799084 309550 170.097
Node 5 798959 309609 169.67
Node 6 798877 309645 169.34
Node 7 798828 309705 170.831
Node 8 799047 309635 171.189
NodeString 6 2 3 10 19 29 40 52 69 90 118
149 183 217 254 292 330 368 405 441 476
513 548 585 621 656 687 716 744 771 797
NodeString 5 171 205 240 278 316 354 391 426 462 500
536 574 610 646 679 710 740 767 793 819
843 867 891 915 939 963 986 1008 1031 1032
```

### Sediment Rating Curve File "user_named.xys"

The sediment rating curve file provides the water discharge versus sediment discharge for each of the size fractions included in the run. Both variables are in cfs or cms depending on the units selected for the project. The lines with “//” are comment lines..

### Guidance for creating a sediment rating curve

When modeling sediment transport with SRH-2D a sediment rating curve may be specified for the upstream inflow boundary condition(s). The sediment rating curve option in SRH-2D requires that a Qs (or sediment discharge in cfs or m3/s) be provided for each size fraction in the run. It would be common for field measurements to provide the sediment concentration as parts per million by weight (ppm-wt) or mg/L. Here is a guideline for converting between such a quantity and the required input for SRH-2D (Qs).

For low sediment concentrations (Cmg/L < 25,000) the conversion from concentration to sediment discharge, Qs is:

${\displaystyle Qs=C/((1,000,000)*SG)*Q}$

Where:

Qs = Sediment discharge in cfs or m3/s
C (in mg/L) = concentration of sediment in inflow (in mg/L)
SG = specific gravity of inflow sediment
Q = volumetric flowrate in cfs or m3/s

For higher concentrations the sediment contribution to the total flow volume should not be ignored. See HDS-6 Section 4.8 (FHWA, 2001) or a sediment transport textbook for exact relationships for high-concentration conditions.

Particle Diameter Thresholds (in mm) must be specified when modeling sediment transport with SRH-2D. These values are entered in the BC Type Parameters dialog accessed by right-clicking on the SRH-2D Boundary Conditions coverage used in the SRH-2D sediment simulation and selecting BC Types.

The number of columns in the sediment rating curve file should correspond to the intervals between the thresholds (or the number of thresholds minus one) plus an additional column at the beginning with the corresponding flow. It is the responsibility of the user to decide how many flows (one row for each) should be entered in the sediment rating curve. A particle size distribution analysis should be performed for the incoming sediment to determine the Qs in each size class in each particle diameter threshold interval. The number of sediment size classes in the sediment gradation curves specified for each layer in the sediment materials coverage don’t necessarily need to match the number of intervals between thresholds.

The SRH-Capacity software developed by the US Bureau of Reclamation may be used to assist in this process of developing a sediment rating curve. For information on the SRH-Capacity software see this page.

#### SEDIMENT RATING CURVE Example

```RATING_CURVE
// Q-vs- Qs rating curve at upstream boundary
// 9 size fraction. 100ppm for cohesive sediment.
35315 1.3326 4.58713 2.49675 3.82647 1.36954 0.21376 0.01986 0.00174 0.00019
54080 2.0408 9.00825 4.97158 8.52648 3.24857 0.45732 0.02603 0.00245 0.00044
81910 3.0909 13.84716 9.12011 18.89248 11.53444 2.91612 0.34379 0.02711 0.00651
117161 4.4212 10.34221 9.51859 23.91257 20.10147 6.71838 1.17766 0.17474 0.03415
178208 6.7248 5.48430 6.92301 20.87747 21.68023 8.27505 1.58578 0.26850 0.05264
238037 8.9825 5.54236 7.73237 26.09735 31.32539 12.73831 2.58504 0.48187 0.12043
```