Dear Chris,

I've run my three bridge opening in HEC-RAS and obtained an acceptable water surface elevation. Although the stagnation points don't seem to be listed correctly in the output, I just used the calculated flow rates for each bridge and ran them separately. The individual analyses have an energy grade elevation at the approach x-section that varies by almost 1' when I use those flow rates. Is this acceptable? What causes the difference?

Anne Daniels
lcdaniels@earthlink.net