headwater calcs
headwater calcs
(OP)
What is the best method to use in calculating headwater elevations? What computer programs are recommended? How do hydraulic grade lines coincide with headwater elevations? If I have a pipe system a few hundred feet long, and I want to know what headwater elevation I have at the upstream open end, will the hydraulic grade lines reflect this?





RE: headwater calcs
You can probably start your HGL calculations at the downstream end of your system based on a variety of boundary conditions (known starting WSEL, pipe crown, rating curve, etc.) and work your way upstream, incorporating headlosses due to friction and junctions. Ultimately, you will have some loss associated with your inlet (be it a headwall, drop inlet, etc.) and you should be able to calculate your upstream headwater elevation.
RE: headwater calcs
A good starting reference is the HEC-22:Urban Drainage Design Manual. As froude has said there's been some recent discussion on "How do you design and storm drain" and also several other threads regarding hydraulic grade line which may be useful for additional reference.