Introduction: This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download at http://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics. I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter. It also helps show sometimes when a parameter is not important.
Discussion: In this blog we look at the Runoff total over the 100 year period, graph the runoff (Figure 1) and show the Mean, Total and Peak Runoff using the Statistics Command in SWMM 5. The Frequency plots shown in Figure 1 are made using event separation time of 6 hours. The number of Runoff Events over the 100 year period is 11,144 events. The details of the simulation are shown in Figure 2.
Figure 1. Runoff from One Watershed for a 100 Year Simulation with SWMM 5 Statistics for Peak, Mean and Total Runoff |
Figure 2. Details of the Simulation Watershed |
[TITLE]
[OPTIONS]
FLOW_UNITS CFS
INFILTRATION GREEN_AMPT
FLOW_ROUTING DYNWAVE
START_DATE 01/01/2500
START_TIME 00:00:00
REPORT_START_DATE 01/01/2500
REPORT_START_TIME 00:00:00
END_DATE 12/31/2599
END_TIME 23:00:00
SWEEP_START 01/01
SWEEP_END 01/30
DRY_DAYS 0
REPORT_STEP 01:00:00
WET_STEP 00:15:00
DRY_STEP 00:30:00
ROUTING_STEP 0:01:00
ALLOW_PONDING NO
INERTIAL_DAMPING NONE
VARIABLE_STEP 0.75
LENGTHENING_STEP 1
MIN_SURFAREA 0
NORMAL_FLOW_LIMITED BOTH
SKIP_STEADY_STATE NO
FORCE_MAIN_EQUATION H-W
LINK_OFFSETS DEPTH
MIN_SLOPE 0
; Added Parameters for QA/QC
MAX_PROCESSORS NO
BYPASS YES
ThetaStorage NO
MAX_ITERATIONS 8
MIN_ITERATIONS 2
TOLERANCE 0.001000
RELAXATION 0.50
AREAWEIGHT 1.00
HYDRAULICWEIGHT 1.00
DWF_GLOBAL 1.0
RDII_GLOBAL 1.0
DEPTH_UNITS
SaveAllData NO
[FILES]
SAVE RAINFALL "C:\Users\Robert E Dickinson\Desktop\Desktop_July2012\RainFall.rff"
[EVAPORATION]
;;Type Parameters
;;---------- ----------
MONTHLY .1 0.1 .1 0.15 0.2 0.3 0.191 0.3 0.2 0.1 0.05 0.05
RECOVERY soil
DRY_ONLY YES
[RAINGAGES]
;; Rain Time Snow Data
;;Name Type Intrvl Catch Source
;;-------------- --------- ------ ------ ----------
RainGage VOLUME 1:00 1.0 FILE "D:\100_years_rainfall.dat" user IN
[SUBCATCHMENTS]
;; Total Pcnt. Pcnt. Curb Snow
;;Name Raingage Outlet Area Imperv Width Slope Length Pack
;;-------------- ---------------- ---------------- -------- -------- -------- -------- -------- --------
MySubCatchment RainGage Storage 10 10 100 0.5 0
[SUBAREAS]
;;Subcatchment N-Imperv N-Perv S-Imperv S-Perv PctZero RouteTo PctRouted
;;-------------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
MySubCatchment 0.02 0.05 0.05 0.1 25 OUTLET
[INFILTRATION]
;;Subcatchment Suction HydCon IMDmax
;;-------------- ---------- ---------- ----------
MySubCatchment 4 1 0.25
[OUTFALLS]
;; Invert Outfall Stage/Table Tide
;;Name Elev. Type Time Series Gate
;;-------------- ---------- ---------- ---------------- ----
Outfall 0 FREE NO
[STORAGE]
;; Invert Max. Init. Storage Curve Ponded Evap.
;;Name Elev. Depth Depth Curve Params Area Frac. Infiltration Parameters
;;-------------- -------- -------- -------- ---------- -------- -------- -------- -------- -------- -----------------------
Storage 1 9 0 FUNCTIONAL 10 0 0 0 0
[CONDUITS]
;; Inlet Outlet Manning Inlet Outlet Init. Max.
;;Name Node Node Length N Offset Offset Flow Flow
;;-------------- ---------------- ---------------- ---------- ---------- ---------- ---------- ---------- ----------
VENANT Storage Outfall 500 0.013 0 0 0 0
[XSECTIONS]
;;Link Shape Geom1 Geom2 Geom3 Geom4 Barrels Culvert Code Transition Multipler
;;-------------- ------------ ---------------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
VENANT CIRCULAR 3 0 0 0 1 0 0 0
[LOSSES]
;;Link Inlet Outlet Average Flap Gate
;;-------------- ---------- ---------- ---------- ----------
[POLLUTANTS]
;; Mass Rain GW I&I Decay Snow Co-Pollut. Co-Pollut. DWF
;;Name Units Concen. Concen. Concen. Coeff. Only Name Fraction Concen.
;;-------------- ------ ---------- ---------- ---------- ---------- ----- ---------------- ---------- ----------
tn MG/L 1 0.0 0.0 0.0 NO * 0.0 0.0
[LOADINGS]
;;Subcatchment Pollutant Loading
;;-------------- ---------------- ----------
[INFLOWS]
;; Param Units Scale Baseline Baseline
;;Node Parameter Time Series Type Factor Factor Value Pattern
;;-------------- ---------------- ---------------- -------- -------- -------- -------- --------
Storage FLOW "" FLOW 1.0 1.0 1
[DWF]
;; Average Time
;;Node Parameter Value Patterns
;;-------------- ---------------- ---------- ----------
Storage FLOW 2 "Hourly"
[HYDROGRAPHS]
;; Rain Gage/
;;Name Month Response R T K IA_max IA_rec IA_ini
;;-------------- ---------------- -------- -------- -------- -------- -------- -------- --------
MANY RainGage
MANY All Short .1 1 1 1 .01 0
MANY All Medium .05 3 3 1 .01 0
MANY All Long .01 5 10 1 .01 0
[RDII]
;;Node Unit Hydrograph Sewer Area
;;-------------- ---------------- ----------
Storage MANY 1
[PATTERNS]
;;Name Type Multipliers
;;-------------- ---------- -----------
soil MONTHLY .01 .10 1 2 1 .10
soil .01 .10 1 2 1 .1
Hourly HOURLY 0.191 0.236 0.251 0.302 0.400 0.463
Hourly 0.703 1.000 0.876 0.670 0.491 0.456
Hourly 0.400 0.358 0.274 0.290 0.373 0.385
Hourly 0.468 0.596 0.640 0.543 0.403 0.364
[REPORT]
INPUT YES
CONTROLS NO
SUBCATCHMENTS ALL
NODES ALL
LINKS ALL
[TAGS]
[MAP]
DIMENSIONS 747573.697 247745.801 753800.907 251809.529
Units Feet
[COORDINATES]
;;Node X-Coord Y-Coord
;;-------------- ------------------ ------------------
Outfall 747879.187 247930.516
Storage 750522.255 249213.382
[VERTICES]
;;Link X-Coord Y-Coord
;;-------------- ------------------ ------------------
[Polygons]
;;Subcatchment X-Coord Y-Coord
;;-------------- ------------------ ------------------
MySubCatchment 747856.752 247967.907
MySubCatchment 747726.887 248390.794
MySubCatchment 747597.022 248813.681
MySubCatchment 747221.312 249101.864
MySubCatchment 747337.291 249659.456
MySubCatchment 747484.496 250917.382
MySubCatchment 749812.998 251702.471
MySubCatchment 753039.238 251624.814
MySubCatchment 753965.941 250721.110
MySubCatchment 753517.852 247990.342
[SYMBOLS]
;;Gage X-Coord Y-Coord
;;-------------- ------------------ ------------------
RainGage 750276.915 250966.450