- If a flood drainage 2m diameter ,1500m long pipe with no fall/gradient is 1. is above sump water level. 2. Is below sump water level what kind of drainage from sump to outflow will there be ?
This 1500 m long , 2m diameter , 1m below flooded road surface from point at right side to sump at left side is horizontal.
My understanding for sufficient drainage is a minimum fall, 1:100 required. Then with a gradient of .01 a pipe of this length should have a 15m fall. There is grating above concrete gutter, above junctions ( about 2m wide gap) in plastic drainpipes where flood water enters system. The question is about what kind of flow rate would be present where the pipe enters the sump that is continuous with the outfall that is at base level of sump ( with not much fall ) Two situations: 1 sump water level below end of horizontal drainpipe. 2 sump water level above end of pipe ?