DeniseS

Hi Chris, I had 1278.00 as the very first elevation of my Elevation-Area Table, and the error was still occurring. I changed the routing method from Outflow Structures to Outflow Curve, and all of the simulations ran smoothly with no errors. There were warnings, but no errors. I appreciate you taking the time to answer my question. Denise

Hello, I've been using HEC-HMS for just about two years now and I'm still learning all of the details of it. I have a detention pond which is draining 1.76 acres onto a state highway. I have put in the Elevation-Area Table in the Paired Data. There is an outlet pipe (the only outlet) of 18"; it's inlet elevation is 1278.00. I'm assuming that is the very bottom of the detention pond, because in the drawing, contours are shown for this pond starting at 1279.00. When I run the 2-year Type II SCS Storm of 3.30 inches, the following error occurs and the process is aborted: "ERROR 40254: