Pond Boss Forums GENERAL QUESTIONS Property Projects & Construction Pond Drain

SGF, if you follow the link that I posted, you should be able to plug in numbers that you generate from the dimensions of the pipe (length and depth that it is underwater, or head pressure) and get the size pipe you need.

If it was me, for a WAG, I'd average out the head pressure at 10'. It'd flow more at higher head, and less at lower head.

Diameter will depend on length of pipe and # of gallons per hour. To get you a jump on the numbers, there are 7.48 gallons in cubic foot.

While it's more $ up front, I agree with having the valve on the pond side of the pipe.