Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? Replacing drain pipe

Hello all-
I recently bought a piece of property with a 2.5 acre lake but the metal overflow pipe is rusting and I am concerned that if it is not replaced in the next few years it may cause a major leak in dam. Any thoughts on the easiest way to replace the overflow pipe would be appreciated. I was thinking about cementing the existing pipe and trenching a new overflow pipe in.

Hello Tdbdds and welcome to Pond Boss. Hang on for some expert opinions. Thanks for posting.

Take a look about 5 or 6 posts down. The same thing is being discussed.

Dear Fingerling,
I had the same problem. After consulting a host of professionals and getting quotes up to $17K to dig out the old drainage system and put in a new, I "sleeved" the old pipe with double-walled HDPE pipe and grouted with bentonite clay for around $200. I got the pipe from Eastern Supply in Winchester VA. (They're incredibly knowledgeable, patient and helpful. I say that with conviction because I knew nothing and they helped me pull this off.) I measured the interior of the old pipe, then got the HDPE with the highest external diameter less than that. Eastern cut the bottom of the pipe to duplicate the profile I need to work with the horizontal pipe, I shoved it in and distributed a bentonite cement around where it entered the old pipe to grout the space between the two. I also purchased a new trash rack for the top. This wouldn't work in all cases, but it's worked out really well for me. The pond is back up to it's original depth, drains well, and the reduced capacity only makes a difference in really heavy, sustained storms, and even then it doesn't get behing enough to flood the emergeny spillway. I'm really happy with it.