Basin Size
Basin Size
(OP)
Hello all
Is there a quick and dirty way to estimate the required size of a basin if I know what the peak inflow to the basin is and I know the maximum discharge of my outlet works? Any help is greatly appreciated.
Scott
Is there a quick and dirty way to estimate the required size of a basin if I know what the peak inflow to the basin is and I know the maximum discharge of my outlet works? Any help is greatly appreciated.
Scott
RE: Basin Size
I'm not quite sure I follow what you're asking, but I'll try to answer. By basin, I'm assuming you mean a detention pond (although I've never heard of a detention pond refered to as a basin). I suppose it would depend on what is going on upstream of the basin. Is the area large (i.e. greate than 150 acres)? are there upstream detention ponds? is there a need for water quality storage? The maximum outflow of the pond is definitely needed however, the peak inflow into the pond has little to do with determining the required volume. You'll need to do either a mass balance approach (i.e. flow in x time - flow out x time = storage requirement), or route a hydrograph through the pond (Haestad Methods PondPack, EPASWMM, etc.). Probably the best thing to do would be to check with your reviewing agency and find out what method they require.
Brian
RE: Basin Size
to see it online.
RE: Basin Size
RE: Basin Size
NRCS TR55 provides a very quick, one page algorithm. Since you already know the peaks in and out, the only other info you need is the SCS curve number (this requires identifying the Hydrologic Soils Group, a list of which is also in TR55) of the watershed, Type of rainfall distribution (per map on page B2) and the runoff amount (inches, not cfs). It is free from the NRCS (your local Conservation District might have copies) and I have used it for years without a problem.