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HWEI
July 11, 2014, 07:33 AM
I have been working on calibrating a sanitary sewer model using some field data we collected last summer. I started the calibration process by using the EPA SSOAP tool to develop RTK values using my storm data. I then input that data into Infoworks CS and set some low baseline rainfall infiltration values (I set groundwater infiltration to 0.01 to turn it off). After running the model multiple time I have adjusted both the ground infiltration and RTK values to zero or almost zero and I am still getting substantially more flow into the system than my data shows actually happens. Are there other variables other than the Ground Infiltration and RTK sets (under the subcatchment group) that I should be adjusting? If not does anyone have any suggestions why I might be getting excessive flow into my system?

I have include a sample site as well as the results below. To me the RTK values should move the curve to the right not all at the start of the storm.

Basin 12
Ground Infiltration
0.500
0.500
0.010
0.500
99.000
0.001
40.000
40.000
392.000
Absolute
402.000
Absolute
RTK
0.001
2.000
0.050
0.001
24.000
36.000
0.100
48.000
60.000

Results
58

Thanks,

Josh

Robert Dickinson
July 16, 2014, 03:47 AM
Hello HWEI,
I would plot or graph just the RDII flow from that Subcatchment to see the response. It looks like you have a very small K1 value of 0.05 which may be making the response UH not smooth. It should not look like the hyetograph. If you still have questions please send us an email to support@innovyze.com Your contributing area may also be too large for the RDII response which accounts for the large flow even though the R1 value is small.

Regards,
Bob Dickinson