Problem

After computing a model an error appears stating "H&H-SewerGEMS stopped working".
Clicking on the button outlined in red above will display the Exception.log file with the following message:

"System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values.
Parameter name: Index was out of range.  Must be non-negative and less than the size of the collection.
Actual value was -1."

Solution

The above errors may be due to RTK values in a RTK Table.

Make sure all values used are within an acceptable range (Components menu > RTK tables).

The RTK parameters are:

R - fraction of precipitation that enters the collection system for that component

T - the time from the precipitation pulse to the peak of that component of the hydrograph

K- the ratio of the time to peak to time to end of hydrograph for that component.

Notes:

• K is usually on the order of 1.5 to 2.5.
• The sum of the R values for all components should be positive but less than 1.
• The default units for T is hours while R and K are dimensionless.
• The error above will appear if a T value less than 1 minute is entered.

See Also

SewerGEMS Help Article "Assembling RTK Parameters"