
NDS 9-in Square Catch Basin Drain Kit with 2-Opening Catch Basin, Green Plastic
How much water can an 18x18 drain handle,we have a river running between the houses
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The amount of water the 18x18 can handle will depend on the grate used and the size of the drainage pipe. For example, a standard slotted plastic grate will handle 264 gallons per minute. A 6" pipe with a slope of 1% will handle 391 gallons per minute...a 4" pipe will handle 135 gallons per minute.
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