Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? How to Fix a Leaky, Rocky ½ Acre Pond?

Thanks in advance for any help and advice.
I have a half acre pond that leaks badly and is now dry.
It was built 20 years ago, and the builder used some local clay on the deepest part, but not the entire pond.
The pond has gone dry the last couple of summers, leaving huge cracks in the clay.
I have a well and solar, so can refill the pond somewhat.
The soil is very rocky with thin soil and huge volcanic boulders, which probably leak
It's down a steep hill, so hard to get equipment and material in and out.
Which should I consider:
1. Rototill and sheepsfoot to compact the cracks and pray? If it doesn't work, reconsider.
2. Use free local clay to supplement the existing clay?
3. Buy 2 truckloads of bentonite and try to get it downhill
4. Use SoilFloc?
5. Rubber/plastic liner, if I can get it down the hill
Thank for your help!

Run the calcs to see how much it'd cost you to get the "free" local clay properly moistened and compacted with a sheepsfoot roller. A liner could be used, they have geotextile liners that hold water very well, aren't that heavy and are VERY puncture/tear resistant. Look at https://www.btlliners.com/

Thanks. I'm pricing liners now. My pond is about 250'x80' and 12' deep. It is steep down to the pond from driveway with a dirt path. What equipment is needed to move/install the liner? Thanks for your help.

Lusk and Otto have written several articles in PB mag about liners. Contact the PB office to see about getting copies. As I recall, they pretty well covered the topic.

Thank you, Dave. I'll get in touch.

When you are pricing liners, ask them what the quoted liner weighs. The one from BTL is pretty light weight compared to others and it's TOUGH.

I've been down the road of a leaking pond and still trying to solve the puzzle.

Given the conditions you stated above, I would go the route of a liner and use an underlayment as an extra barrier because of the rocky soil. If you have boulders, clay won't do much good unless removed or buried deep. I wish I would have gone this route, but was talked out of it by my 2nd contractor. I have used a lot of polymer and would not recommend it.

Rolls of liner weigh up to 2500lbs so a mini excavator or bigger skid steer will be needed to unload. You will need to dig a ditch on top of the bench 6-10 feet from the high water line and "tuck" the liner under 18"-24" of soil to hold it in place. Slopes should be no steeper than 3:1 or less so it doesn't stretch and tear with the weight of the water. Welding the seems is key to the install, so be sure to take your time.

Thank you for sharing your experiences. Very helpful as I consider my options.

Thanks everyone for your help and advice. TJ spent hours with me on the phone and has been incredibly helpful as I think through my options.

I once asked Mile Otto about leaks. He said that the best way to be sure a pond leaks is to let him build it. He told me “Get over it. Dirt is porous and water gets through it.”.

That is true, BUT how MUCH it leaks per day is the question. Dropping 1" per day above evap rate to me is not acceptable. Dropping 1/8" per day over evap rate would be.