STORM SEWER SIZING
STORM SEWER SIZING
(OP)
I have been asked to show the 12" gravity storm sewer on site can handle the 4" gravity drain tile discharge around a building. Does anyone know if this is possible? Storm sewer is sized per rational method for the 10yr storm event. Drain tile around building is used for subsurface waters(specifically 2.5' below finished floor for waterproofing drain board against foundation) which in my opinion is very variable and does not discharge at the same time as the storm event. Any thoughts?





RE: STORM SEWER SIZING
RE: STORM SEWER SIZING
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RE: STORM SEWER SIZING
I agree with CVG that it is good practice to minimize the possibility of a storm sewer backing up into the foundation drain.
It is a simple exercise to show that there is additional capacity in the 12-Inch storm sewer for full flow from a 4-Inch pipe.
RE: STORM SEWER SIZING
Add the ten year rational flow to the predicted flow from the drain tile, and check that Q in your 10 inch pipe. If you don't know the flow from the drain tile, calculate the flow in a 4" pipe at capacity and use that.
Or am I not understanding your question?
Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com