Applies To
Product(s):	SewerGEMS, CivilStorm
Version(s):	08.11.XX.XX and higher

Problem

When I run my model with EPA SWMM catchments I get a user notification that says,  "One or more EPA SWMM catchments failed to compute. Check your EPA-SWMM input data and try again." How do I fix this?

Solution

First, if using the Explicit (SWMM) solver, check the Calculation Summary (from the Analysis menu) and look at the report tab for any additional details on the failure.

Also, if you are using an older version, upgrading may resolve the issue: Downloading OpenFlows Software

Also if you are using the Implicit solver, try these steps:

1) Go to Analysis > Calculation Options and change the solver from Implicit to Explicit (SWMM).

2) Open your flextable for your catchments and add the field called "Drying Time (Days)".

3) Sort your flextable in Ascending or Descending order on this field and change all the values of the catchments that have a 0 to any value larger than 0. The value can be 0.01 if you want it to be as close to 0 as possible.

4) Go back to Analysis > Calculation Options and change the solver from Explicit (SWMM) back to Implicit (if desired).

5) Compute the model again and that should resolve your issue.