Pond Boss Forums Thread Like Summary - More Dam issues

I was going to add this to my original thread but thought of starting a new one here related to the dam. I've lost 7" of water in 24 days and rain seasoning coming to an end, we are now in our 3rd summer without a full pond.

Last night, I drilled 6 test holes with a spud bar in the backside of my dam a couple feet below the current water line as best as I could tell. It has become clear the dam is not holding and was improperly built. The new "pond side" core trench helped and we feel that the bottom is sealed. We think there is rock (bedrock/sandstone) beneath the dam was not removed and certain the dam was not compacted in proper lifts.

We are now thinking of building a new dam, within/behind the first dam. Water is hard enough to come by so I want to do everything we can to keep what we have without pumping out.

Does anyone have experience in this type of repair?

.29” daily without factoring atmospheric influences (evaporation) and you’re likely under .20” daily of leak loss. In my industry we don’t even consider that a leak. IIRC Your pond was constructed too large for the watershed to support and there’s no opportunity for supplemental irrigation (well) aside from creek pumping. Going from 2-3” daily loss to .25” is in my opinion money very well invested and nothing short of miraculous. You reduced your loss by 95% or better - what were your expectations? Your results sure blew my predictions out of the water.

Yeah, I spoke to TJ a bunch, he knows the story. I just confirmed the problem yesterday and think it's bigger than just a couple of leech spots.

Ryan - .3" daily vertical loss and likely .10-.15" due to evaporative loss this Spring, so you may be looking at .2" daily loss due to dam seepage. I would seriously consider whether it's worth further investment of rehab or polymer chasing such a minor leak. Anything 1/3" or less daily loss we consider in the pond construction business as a successful project provided you're living in an area with decent annual precipitation [25" or greater]. It's your $, and I'll always help however I can, but if it were me I'd count my blessings and adopt a holding pattern.

However, your scenario is unique that you can't pop a well for supplemental irrigation and your watershed is limited, so if you elect to do pursue addressing the poor dam construction/seepage I suggest comparing the cost of core trench work vs. treating the dam face with a polymer application. I'd wager 3-4 units would address your dam seepage successfully at a fraction of the cost/time of rehab. I know you've already spoken to Drew Hay out of PA [one of the best pond builders on the planet], and he could likely provide a rough estimate on dam rehab project.

I'm glad your main basin is holding well following rehab and polymer - we just never anticipated your dam also being an issue. Reach out whenever you need me.