Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? Draining without breaking the seal

I live in a small community with a 29 acre pond/lake. We currently have a problem with leeches. One suggestion has been to drain the lake and clean up the shoreline. Our concern is it is clay lined and that we would break the seal. We've been told that if we do it in the winter and only drain it for a couple weeks we should be ok. The other idea was more sun fish but it seems the bass are eating the sunfish. Any suggestions or experience with draining and scraping/cleaning without breaking the clay liner. If it helps the lake is in the the high desert in california.

Any input would be appreciated.

Pure clay exposed to sunlight is certainly prone to crack. However, it would probably expand when new water was added. But, it might not be able to reseal itself. I'm just not sure.

What temp are the winters?

On average it's in the 60's during the day and gets down to the 40's at night. A couple of times through the winter it does get down in the teens at night but that is rare.

We were also thinking about just draining it 30%. That way the water should get sucked up by the drying clay?

I drain my ponds on a regular basis and even see massive cracks in the clay. When I refill with clay I have no problems.

TBHWY, I think draining to control leeches is pretty extreme and not necessary. I like the fish route better.

I'm not sure the clay will really dry. It seldom does in a larger impoundment. If you try to leave 30%, wouldn't the leeches just go to that area?

I know almost nothing about leeches. Could they stay alive in small pools or wet areas?

Another consideration might be the age of the pond/lake. Runoff carries sediment that sinks to the bottom. When a water hole is drained, there is usually enough junk on the bottom that it can take a considerable time to dry. It can resemble pudding and leeches might be able to stay alive in that. Especially in the moderate temps that you have.

It might be better to try and find a bunch of larger sunfish that didn't easily fit in a predators mouth. What kind of sunfish do you have there? Their reproduction might be a consideration.

BTW, it hit 107 degrees here yesterday. Your weather sounds like paradise. Actually, I'm leaving next Tuesday to spend 2 weeks on Bremerton Island. Temps will be in the mid 70's for a high. Sounds like paradise.

I like the fish solution as with any body of water with leeches, there are not the right kind of fish in it to control them, or enough fish. Also I believe draining will not kill the leeches at all, they will simply burrow into the mud/muck and wait. They can also crawl around on moist ground (dew) looking for better habitat for quite some distance. They are tough little buggers.