Our pond recently started leaking again and I finally figured out what the issues are. We have a 1.5 acre pond. we cut the dam down 5 feet last year and widened it about 15 yards with the excess dirt. The pond is 40 years old or more and was built in a very rocky area. the area to the right of the dam has some spots that are opening up like mini sink holes and water is just draining straight out It doesn't appear to be ending up behind the dam anywhere it is just going straight down into the earth. I have been filling the holes with concrete as I find them and found 4 more over the weekend so I filled the holes were hundreds of pounds of concrete. My question is would it be better to rent an excavator and dig out the 20 yard area or just hire a concrete truck to come in when it dries out and dump concrete on top of the ground to seal off the holes that keep opening up? It appears to be isolated to around a 20 yard bank that goes up to the dam. One of the holes was the size of a basketball and draining the pond down 4 inches over night.

thanks for any advice,

Im by far an expert. Just my thoughts here... Unless you do the whole damn i think you will waste your money doing the concrete. I would think repairing it would be the better way to go. I have never dealt with any type of sink hole or leak. So take my thought for what they cost ya. 4 inches over night is pretty big for sure. The problems lies way before just the surface hole. Since you say its not leaking out the damn its going into the earth. It could be a humugous hole that you dont see at this time. Might be a good idea to have the pros look into it.

Sorry to hear about your leaking issues - I don't think concrete will help seal your leaks, I recommend installing a clay liner with high plasticity clay up to 24" in 6" lifts or treating the leaking areas with polymer which is designed to seal rock, shale, gravel, sand and poorly compacted material. Feel free to reach out anytime I help families nationwide with leak issues exploring solutions. My time is always free to my Pond Boss family, will help in any manner possible.

tj@hudlandmgmt.com

TJ,
we spent a couple thousand on polymers from Polymer Innovations when we first bought the pond and it was like flushing money down the drain. I'm sure they work well in some cases but they would not seal any of the leaks we had initially. I poured it directly into one of the holes and it did not work at all so I appreciate the advice. I'll investigate the clay liner. Concrete worked well with one hole last year and that hole is still sealed but a few more have opened up. I thought about digging them out and bringing in some clay but I'm a little worried if I do that I might have to drain a lot of the pond to do the work. I know the concrete is like a bandaid but it is really cheap and worked ok on one hole I found last year. Ideally a D5 Dozer compacting the side would work if it didn't get stuck or sink LOL but getting the guy who cut down our dam back out would be almost impossible.

I'd dig the area out with an excavator and pack clay in there, in 6"-8" layers, compacting that layer and then adding another layer until you have 18"-24" thick packed clay. Without doing that I think you'll be constantly chasing another spot that starts to leak.

I wasn't aware Polymer Innovation worked in pond sealing - no clue of what polymer they use but it's unfortunate their product didn't work. We're successful on over 90% of our projects but we use a different polymer combination most likely.

A dozer will not compact material to affect a seal, they are meant to bridge material, not compact it. I would excavate, apply a polymer liner, then a few 6" lifts of high plasticity clay compacted with a sheepsfoot roller or at the very least rubber wheel equipment up to 18-24" depth per Scott above.

You're welcome to reach out anytime - hope whatever you do works for you. Leaking ponds stink.

Without draining it I won't be able to compact it other than with an excavator. I think we can dig it out and bring in new clay but bringing a roller in is out of the question. I'm not sure the costs yet we have already spent a small fortune on this pond and I'm not sure the ROI is worth it. It gets down to a certain level and doesn't go any lower. If I hit the lottery it would be a no brainer to redo it. I appreciate the advice. Waiting to hear from my excavator guy on a costs. It would have to be done over the summer in the dry season. Right now it's rained so much we couldn't get anything big back to it anyways and since we never had winter it never froze. Probably with our wheat we are looking at late June or July before I combine the wheat. I thought about renting a bobcat E50 but not sure it is powerful enough to dig through some of the rock I think we would hit.

the polymer innovations company we used was located in Australia not the one in the US. its a .AU address just an FYI and we bought the water plug type

Oh yeah, those guys...makes sense. Wish we had connected earlier - could have saved you a lot of money and probably resolved the leak. Their polymer is only linear polymer, a flocculant, and it lacks the crosslink polymer we use for all my buddies on Pond Boss. If you ever want to bounce ideas around I'm an email away - fixing leaking ponds can be really tough and expensive been there done that too many times.