Working Principles¶
EPA-SWMM 5.0¶
- SWMM 5.0 is a dynamic rainfall-runoff simulation model, released by the environmental protection agency of The United States of America,
used for single event or long-term (continuous) simulation of runoff quantity and quality from primarily urban areas. The runoff component of SWMM operates on a collection of subcatchment areas that receive precipitation and generate runoff and pollutant loads. The routing portion of SWMM transports this runoff through various drainage network components:
- a system of pipes,
- channels,
- storage/treatment devices,
- pumps, and
- regulators.
EPA has recently extended SWMM 5 to explicitly model the hydrologic performance of specific types of low impact development (LID) controls, such as:
- porous pavement,
- rain gardens,
- green roofs,
- street planters,
- rain barrels,
- infiltration trenches, and
- vegetative swales.
SWMM 5.0 has its own, easy to use graphical user interface (Shown below)
EPA SWMM 5.0 Desktop
Downloading and Installing SWMM 5.0¶
EPA SWMM 5.0 can be downloaded from US-EPA web site . The software is public domain, therefore free to use.
It works on Windows and Linux (use with Wine ). Should work fine on Mac OS X (with Wine) too, but this was not confirmed at the time of writing.
SWMM 5.0 Input file format¶
SWMM 5.0 has a text-based input file format. When you build a network model on the SWMM 5.0 Desktop and save it, the software in-fact saves a text based input file.
This file has extension inp (e.g. StorageEx.inp). The format of the file is self-explanatory and looks like the following:
[TITLE]
[OPTIONS]
FLOW_UNITS LPS
INFILTRATION CURVE_NUMBER
FLOW_ROUTING DYNWAVE
START_DATE 10/28/2011
START_TIME 00:00:00
REPORT_START_DATE 10/28/2011
REPORT_START_TIME 00:00:00
END_DATE 10/28/2011
END_TIME 06:00:00
SWEEP_START 01/01
SWEEP_END 12/31
DRY_DAYS 0
REPORT_STEP 00:01:00
WET_STEP 00:01:00
DRY_STEP 00:01:00
ROUTING_STEP 0:00:01
ALLOW_PONDING NO
INERTIAL_DAMPING PARTIAL
VARIABLE_STEP 0.75
LENGTHENING_STEP 0
MIN_SURFAREA 0
NORMAL_FLOW_LIMITED SLOPE
SKIP_STEADY_STATE NO
FORCE_MAIN_EQUATION H-W
LINK_OFFSETS DEPTH
MIN_SLOPE 0
[EVAPORATION]
;;Type Parameters
;;---------- ----------
CONSTANT 0.0
DRY_ONLY NO
[RAINGAGES]
;; Rain Time Snow Data
;;Name Type Intrvl Catch Source
;;-------------- --------- ------ ------ ----------
Gage1 VOLUME 0:03 1.0 TIMESERIES ABM10yrs2hrs
[SUBCATCHMENTS]
;; Total Pcnt. Pcnt. Curb Snow
;;Name Raingage Outlet Area Imperv Width Slope Length Pack
;;-------------- ---------------- ---------------- -------- -------- -------- -------- -------- --------
A2 Gage1 J4 96.9 40.80 1000 4.13 0
A1 Gage1 J1 33.8 29.24 1000 4.13 0
A3 Gage1 J3 50.7 32.17 1000 4.13 0
A4 Gage1 J10 30.0 25.17 1000 4.13 0
A5 Gage1 J9 25.5 10.00 1000 4.13 0
E1 Gage1 J8 34.9 0 1000 1.86 0
[SUBAREAS]
;;Subcatchment N-Imperv N-Perv S-Imperv S-Perv PctZero RouteTo PctRouted
;;-------------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
A2 0.01 0.1 0.05 0.05 25 OUTLET
A1 0.01 0.1 0.05 0.05 25 OUTLET
A3 0.01 0.1 0.05 0.05 25 OUTLET
A4 0.01 0.1 0.05 0.05 25 OUTLET
A5 0.01 0.1 0.05 0.05 25 OUTLET
E1 0.01 0.1 0.05 0.05 25 OUTLET
[INFILTRATION]
;;Subcatchment CurveNum HydCon DryTime
;;-------------- ---------- ---------- ----------
A2 90 0.5 7
A1 90 0.5 7
A3 90 0.5 7
A4 90 0.5 7
A5 90 0.5 7
E1 70 0.5 7
[JUNCTIONS]
;; Invert Max. Init. Surcharge Ponded
;;Name Elev. Depth Depth Depth Area
;;-------------- ---------- ---------- ---------- ---------- ----------
J2 45.633 1.8 0 0 0
J5 47.381 1.8 0 0 0
J6 41.909 1.8 0 0 0
J8 23.459 3 0 0 0
J9 37.689 2 0 0 0
J10 32.424 2 0 0 0
[OUTFALLS]
;; Invert Outfall Stage/Table Tide
;;Name Elev. Type Time Series Gate
;;-------------- ---------- ---------- ---------------- ----
J12 15.649 FREE NO
[STORAGE]
;; Invert Max. Init. Storage Curve Ponded Evap.
;;Name Elev. Depth Depth Curve Params Area Frac. Infiltration Parameters
;;-------------- -------- -------- -------- ---------- -------- -------- -------- -------- -------- -----------------------
J11 27.159 1.8 0 FUNCTIONAL 500 0 0 0 0
J3 36.437 1.8 0 FUNCTIONAL 500 0 0 0 0
J4 52.853 1.8 0 FUNCTIONAL 500 0 0 0 0
J1 55 1.8 0 FUNCTIONAL 500 0 0 0 0
J7 29.589 1.8 0 FUNCTIONAL 500 0 0 0 0
[CONDUITS]
;; Inlet Outlet Manning Inlet Outlet Init. Max.
;;Name Node Node Length N Offset Offset Flow Flow
;;-------------- ---------------- ---------------- ---------- ---------- ---------- ---------- ---------- ----------
T4-1 J9 J10 117 0.02 0 0 0 0
T4-2 J10 J11 117 0.02 0 0 0 0
T4-3 J11 J8 60 0.02 1.5 0 0 0
T1-1 J1 J2 242 0.02 1 0 0 0
T1-2 J2 J3 400 0.02 0 0 0 0
T2-1 J4 J5 288 0.02 1 0 0 0
T2-2 J5 J6 288 0.02 0 0 0 0
T2-3 J6 J3 288 0.02 0 0 0 0
T3-1 J3 J7 428 0.02 1 0 0 0
T3-2 J7 J8 342 0.02 1.0 0 0 0
T5 J8 J12 235 0.01 0 0 0 0
[XSECTIONS]
;;Link Shape Geom1 Geom2 Geom3 Geom4 Barrels
;;-------------- ------------ ---------------- ---------- ---------- ---------- ----------
T4-1 CIRCULAR 2 0 0 0 1
T4-2 CIRCULAR 2 0 0 0 1
T4-3 CIRCULAR 2 0 0 0 1
T1-1 CIRCULAR 1.2 0 0 0 1
T1-2 CIRCULAR 1.2 0 0 0 1
T2-1 CIRCULAR 2 0 0 0 1
T2-2 CIRCULAR 2 0 0 0 1
T2-3 CIRCULAR 2 0 0 0 1
T3-1 CIRCULAR 1.5 0 0 0 3
T3-2 CIRCULAR 1.5 0 0 0 2
T5 RECT_OPEN .4 3 0 0 1
[LOSSES]
;;Link Inlet Outlet Average Flap Gate
;;-------------- ---------- ---------- ---------- ----------
[TIMESERIES]
;;Name Date Time Value
;;-------------- ---------- ---------- ----------
;2hr
2hrRainfall 0:00 0.00
2hrRainfall 0:01 0.12
2hrRainfall 0:02 0.12
2hrRainfall 0:03 0.12
2hrRainfall 0:04 0.12
2hrRainfall 0:05 0.12
2hrRainfall 0:06 0.13
2hrRainfall 0:07 0.13
2hrRainfall 0:08 0.13
2hrRainfall 0:09 0.14
2hrRainfall 0:10 0.13
2hrRainfall 0:11 0.14
2hrRainfall 0:12 0.15
2hrRainfall 0:13 0.15
2hrRainfall 0:14 0.14
2hrRainfall 0:15 0.16
2hrRainfall 0:16 0.16
2hrRainfall 0:17 0.16
2hrRainfall 0:18 0.17
2hrRainfall 0:19 0.17
2hrRainfall 0:20 0.17
2hrRainfall 0:21 0.17
2hrRainfall 0:22 0.18
2hrRainfall 0:23 0.19
2hrRainfall 0:24 0.19
2hrRainfall 0:25 0.2
2hrRainfall 0:26 0.2
2hrRainfall 0:27 0.2
2hrRainfall 0:28 0.21
2hrRainfall 0:29 0.22
2hrRainfall 0:30 0.23
2hrRainfall 0:31 0.23
2hrRainfall 0:32 0.24
2hrRainfall 0:33 0.25
2hrRainfall 0:34 0.26
2hrRainfall 0:35 0.27
2hrRainfall 0:36 0.28
2hrRainfall 0:37 0.29
2hrRainfall 0:38 0.3
2hrRainfall 0:39 0.31
2hrRainfall 0:40 0.33
2hrRainfall 0:41 0.35
2hrRainfall 0:42 0.37
2hrRainfall 0:43 0.39
2hrRainfall 0:44 0.41
2hrRainfall 0:45 0.43
2hrRainfall 0:46 0.46
2hrRainfall 0:47 0.5
2hrRainfall 0:48 0.53
2hrRainfall 0:49 0.57
2hrRainfall 0:50 0.62
2hrRainfall 0:51 0.67
2hrRainfall 0:52 0.74
2hrRainfall 0:53 0.81
2hrRainfall 0:54 0.91
2hrRainfall 0:55 1.02
2hrRainfall 0:56 1.17
2hrRainfall 0:57 1.34
2hrRainfall 0:58 1.58
2hrRainfall 0:59 1.89
2hrRainfall 1:00 2.34
2hrRainfall 1:01 2.1
2hrRainfall 1:02 1.73
2hrRainfall 1:03 1.45
2hrRainfall 1:04 1.24
2hrRainfall 1:05 1.08
2hrRainfall 1:06 0.96
2hrRainfall 1:07 0.86
2hrRainfall 1:08 0.78
2hrRainfall 1:09 0.7
2hrRainfall 1:10 0.65
2hrRainfall 1:11 0.59
2hrRainfall 1:12 0.55
2hrRainfall 1:13 0.51
2hrRainfall 1:14 0.48
2hrRainfall 1:15 0.45
2hrRainfall 1:16 0.43
2hrRainfall 1:17 0.39
2hrRainfall 1:18 0.38
2hrRainfall 1:19 0.36
2hrRainfall 1:20 0.34
2hrRainfall 1:21 0.33
2hrRainfall 1:22 0.32
2hrRainfall 1:23 0.3
2hrRainfall 1:24 0.29
2hrRainfall 1:25 0.27
2hrRainfall 1:26 0.26
2hrRainfall 1:27 0.26
2hrRainfall 1:28 0.24
2hrRainfall 1:29 0.24
2hrRainfall 1:30 0.23
2hrRainfall 1:31 0.22
2hrRainfall 1:32 0.22
2hrRainfall 1:33 0.21
2hrRainfall 1:34 0.2
2hrRainfall 1:35 0.2
2hrRainfall 1:36 0.19
2hrRainfall 1:37 0.18
2hrRainfall 1:38 0.18
2hrRainfall 1:39 0.18
2hrRainfall 1:40 0.17
2hrRainfall 1:41 0.17
2hrRainfall 1:42 0.16
2hrRainfall 1:43 0.16
2hrRainfall 1:44 0.15
2hrRainfall 1:45 0.15
2hrRainfall 1:46 0.15
2hrRainfall 1:47 0.15
2hrRainfall 1:48 0.14
2hrRainfall 1:49 0.14
2hrRainfall 1:50 0.14
2hrRainfall 1:51 0.14
2hrRainfall 1:52 0.13
2hrRainfall 1:53 0.13
2hrRainfall 1:54 0.13
2hrRainfall 1:55 0.13
2hrRainfall 1:56 0.13
2hrRainfall 1:57 0.12
2hrRainfall 1:58 0.12
2hrRainfall 1:59 0.12
2hrRainfall 2:00 0.11
;Rainfall Data
ABM10yrs2hrs 0:00 0
ABM10yrs2hrs 0:03 0.36
ABM10yrs2hrs 0:06 0.38
ABM10yrs2hrs 0:09 0.40
ABM10yrs2hrs 0:12 0.42
ABM10yrs2hrs 0:15 0.45
ABM10yrs2hrs 0:18 0.48
ABM10yrs2hrs 0:21 0.52
ABM10yrs2hrs 0:24 0.56
ABM10yrs2hrs 0:27 0.61
ABM10yrs2hrs 0:30 0.67
ABM10yrs2hrs 0:33 0.74
ABM10yrs2hrs 0:36 0.82
ABM10yrs2hrs 0:39 0.93
ABM10yrs2hrs 0:42 1.08
ABM10yrs2hrs 0:45 1.27
ABM10yrs2hrs 0:48 1.54
ABM10yrs2hrs 0:51 1.94
ABM10yrs2hrs 0:54 2.58
ABM10yrs2hrs 0:57 3.75
ABM10yrs2hrs 1:00 6.33
ABM10yrs2hrs 1:03 4.75
ABM10yrs2hrs 1:06 3.07
ABM10yrs2hrs 1:09 2.22
ABM10yrs2hrs 1:12 1.71
ABM10yrs2hrs 1:15 1.39
ABM10yrs2hrs 1:18 1.16
ABM10yrs2hrs 1:21 1.00
ABM10yrs2hrs 1:24 0.88
ABM10yrs2hrs 1:27 0.78
ABM10yrs2hrs 1:30 0.70
ABM10yrs2hrs 1:33 0.64
ABM10yrs2hrs 1:36 0.58
ABM10yrs2hrs 1:39 0.54
ABM10yrs2hrs 1:42 0.50
ABM10yrs2hrs 1:45 0.47
ABM10yrs2hrs 1:48 0.44
ABM10yrs2hrs 1:51 0.41
ABM10yrs2hrs 1:54 0.39
ABM10yrs2hrs 1:57 0.37
ABM10yrs2hrs 2:00 0.35
[REPORT]
INPUT NO
CONTROLS NO
SUBCATCHMENTS ALL
NODES ALL
LINKS ALL
[TAGS]
[MAP]
DIMENSIONS 0.000 0.000 10000.000 10000.000
Units None
[COORDINATES]
;;Node X-Coord Y-Coord
;;-------------- ------------------ ------------------
J2 5415.068 1893.131
J5 6566.084 1307.978
J6 6360.316 1809.538
J8 5138.567 3802.918
J9 4418.378 2889.821
J10 4424.808 3153.462
J12 5312.184 5063.248
J11 4752.751 3571.429
J3 5595.115 2336.819
J4 6823.294 1140.791
J1 4778.472 1417.292
J7 5325.044 3102.020
[VERTICES]
;;Link X-Coord Y-Coord
;;-------------- ------------------ ------------------
T4-2 4739.891 3397.812
T4-3 5035.683 3571.429
T4-3 5042.113 3706.464
T3-2 5337.905 3732.185
[Polygons]
;;Subcatchment X-Coord Y-Coord
;;-------------- ------------------ ------------------
A2 9137.862 940.587
A2 9302.164 1556.721
A2 8390.285 2526.106
A2 7379.825 2567.182
A2 7429.116 1400.634
A1 4086.563 458.062
A1 4160.500 975.615
A1 4669.837 950.970
A1 5548.856 1452.093
A1 5581.716 310.190
A1 4867.000 195.178
A3 6297.935 2800.132
A3 6946.737 3271.194
A3 7907.907 3139.752
A3 7940.767 3410.852
A3 7293.018 3745.043
A3 6971.382 4602.045
A3 6585.271 4429.527
A3 6420.969 3714.811
A3 5955.091 2959.011
A4 3550.123 3206.322
A4 3342.244 2942.475
A4 2918.491 3086.392
A4 2478.747 3030.424
A4 3070.403 4013.851
A4 3686.044 3917.907
A5 4226.039 1863.728
A5 3682.356 1607.877
A5 3442.496 1815.756
A5 3554.430 1975.662
A5 3466.482 2207.527
A5 3826.272 2647.271
A5 4337.974 2719.229
A5 4689.769 2567.318
E1 4365.046 4144.795
E1 4518.867 4808.151
E1 4586.164 5202.318
E1 4481.613 5204.819
E1 3818.829 4472.268
E1 3722.900 4062.388
[SYMBOLS]
;;Gage X-Coord Y-Coord
;;-------------- ------------------ ------------------
Gage1 9936.709 6075.949
How SWMM5-EA exploits the input file¶
Problems of metaheuristics [1] involve solving a problems with various input parameters. For example a problem
of calculating optimal sizing of a number of detention storages involve running SWMM 5.0 model with different values for
detention storage sizes. Example 1 is such a problem. How SWMM5-EA facilitates this process of
running SWMM with different values for a set of variables is by using a ‘template‘ system. SWMM5-EA marks a number of locations in the input file with special space-holders (We use symbols like @!v1!@). For example the [STORAGE] section of our swmm input file:
[STORAGE]
;; Invert Max. Init. Storage Curve Ponded Evap.
;;Name Elev. Depth Depth Curve Params Area Frac. Infiltration Parameters
;;-------------- -------- -------- -------- ---------- -------- -------- -------- -------- -------- -----------------------
J11 27.159 1.8 0 FUNCTIONAL 500 0 0 0 0
J3 36.437 1.8 0 FUNCTIONAL 500 0 0 0 0
J4 52.853 1.8 0 FUNCTIONAL 500 0 0 0 0
J1 55 1.8 0 FUNCTIONAL 500 0 0 0 0
J7 29.589 1.8 0 FUNCTIONAL 500 0 0 0 0
is templated like:
[STORAGE]
;; Invert Max. Init. Storage Curve Ponded Evap.
;;Name Elev. Depth Depth Curve Params Area Frac. Infiltration Parameters
;;-------------- -------- -------- -------- ---------- -------- -------- -------- -------- -------- -----------------------
J11 27.159 1.8 0 FUNCTIONAL !@v1@! 0 0 0 0
J3 36.437 1.8 0 FUNCTIONAL !@v2@! 0 0 0 0
J4 52.853 1.8 0 FUNCTIONAL !@v3@! 0 0 0 0
J1 55 1.8 0 FUNCTIONAL !@v4@! 0 0 0 0
J7 29.589 1.8 0 FUNCTIONAL !@v5@! 0 0 0 0
This is done by user by simply blocking the number that need to be a place-holder and pressing a button (See figure below)
How to create place-holders in a SWMM input file.
Then the optimization engine will fill these place-holders with relevent values during each evaluation step.
| [1] | Metaheuristic methods optimizes a problem by iteratively trying to improve a candidate solution with regard to a given measure of quality. The Evolutionary computation method used in SWMM5-EA is a metaheuristic method. |