Pond Boss Forums POND CONSTRUCTION Soil questions Renovated pond dropping a little

We finished completely renovating a 47 year old 0.3 acre pond last August. It was completely dried out and re-dozed, with almost 5 feet of sludge removed. Got a good rain, filled about 1/3 and stocked fingerlings in late September. Recently, we had flooding rains, and the pond came up almost 3 feet in two days to stand about 3/4 full. By mid day last Friday, the water had ceased to run in. Since then the level has dropped about an inch. I don't see any leaks on the back of the dam. Could it be losing water due to saturation of the clay in the dam, which runs about 2/3 of the perimeter? The dam is nearly pure orange-red and a little blue clay, very little rock, and was not deeply disturbed during the renovation, but it did dry out very well before refilling. Thanks for any insight.

Yep, new ponds wick a lot of water into the surrounding soil.

It has only dropped 2 inches in six days. We have had no rain and quite a bit of wind, so it is mostly evaporation, I think.

The clay in the dam may have cracked when it dried. Clay needs some moisture to swell, compact, and seal well. If it had dried, there could have been cracks that formed as the clay shrunk. Filling quickly, the clay won't remoisten and swell as fast as the water coming in.

It was up 9 inches when the rain stopped Monday morning, and had spread a lot into shallow, undisturbed areas on the upper end. By this morning (Wed), it has dropped an inch. Don't see any leaks below the dam. I guess still saturating?

Should be good to go after it wicks it all up. I went through the same thing with mine. At .3 acres you are looking at about 8000 gallons per inch. I would bet the ground wants at least that much.

I pumped three inches of water into the pond Thursday. By this morning (Sat), had lost 1-1/4 inches. Still no obvious leaks. This pond used to hold water well before the renovation and removal of four to five feet of mud and sludge. The area of the pond was dried out for a couple of months total before, during, and after the renovation. The original dam was not deeply disturbed, and is very wide and only about six feet high. The rest of the pond is excavated into a bowl of nearly pure orange colored clay with only a few rocks, and they are very small. The upper end backs up into the edge of a hayfield. Could someone please explain absorption and how long to expect it to occur? Will the underwater soil structure gradually change? BTW, We left weeds and such on the upper end edges to hold the soil against runoff.

You are pumping water into virgin dirt every time it rises.

Patience!!!!!!!.... It takes a little while to saturate............... I agree, a lot of your loss is likely due to evaporation; hence the smoke on the water during these cold mornings.

How big is the pipe you are pumping through? I am using 2 inch poly.

Update: Pond went down six inches in nine mostly warm and windy days, but now is back up eight inches and still slowly rising after nearly two inches of rain. About ten inches to go until gets to grassy spillway. It holds better after a rain than after a pumping session.

Makes sense to me if the rain saturated the soil surrounding the pond. Soil can only hold so much water. Once it's saturated it will not pull water from the pond and may very well be shedding excess water to the pond right now.

Pond came up nine inches during last rain. It is now down four inches in five days. Seems like it will never fill. I may have to abandon the project if it won't hold water. The bottom and sides are clay good enough to make pottery. Can't see how it is losing so much. When I dug the post holes for the little dock,the clay was so dense and sticky I had a very difficult time with the post hole diggers.

It hasn't been a month yet. It will be fine. Don't look at it for awhile. A watched pond never fills.

Five inches of rain and still coming down. The pond is over the emergency (only) spillway now by about three or so inches, but that spillway is wide and flat, so no erosion that I could see. Backed way up into the field, lots of shallows under six inches deep. About 1/4 acre at what I would call normal full pool, but over 1/3 acre now.

Edit: Here are some pictures

Edit: As of 9:00 PM, we have received 8.8 inches of rain with this storm since yesterday, and still raining.

This storm has stretched a lot of water holes.

As you can see, the minnow pond and main pond joined at high water. Before renovation, a neighbor said he never saw that pond close to spillway in 40 years, but we have increased the watershed by maybe 50%.
No worries about the minnow pond, as there were no minnows in it yet plus I do not have LMB yet, and it's easily pumped out in a couple of hours and can be refilled with screened creek water in about three hours.
Here's a photo from today. I didn't find any fish in the field below the spillway.

A couple of weeks before starting to renovate the pond, my dirt mover brought his backhoe and cut a 16 inch wide trench through the deepest part of the dam, which allowed the pond to drain about 2/3 of its volume (we pumped the rest using the same trench). After renovation was almost completed, he filled the trench, but was not able to compact it fully as it is about six feet deep, and about four feet into the maximum water level. It settled some (like a grave does) and I packed and hammered pure clay into it to bring it back above the level of the rest of the dam. It has not settled any more, even after our 10.4 inch rain early last week. Since the pond got close to full (about a month ago), it has developed a fairly significant seep through the former trench. The water is not visibly flowing, but the clay is very soft and wet on top and saturated on the back of the dam where the trench was, and a small amount of water has pooled. The part that is seeping on the inside of the dam could not be more than about 30 square feet. The original core trench he cut through was very dense clay like pottery clay, very hard to dig. I think the seep is going through that area, then spreading out under the toe of the dam, which is why I am not seeing any water running. There is an area about 40 feet long centered on that former trench that is wet behind the dam at the very bottom. I am losing about 7/8 inch per day, but still don't see any water actually running (only seeping) out behind the dam. I have just ordered, and will be trying some soil-floc (55 pounds) sometime next week. The pond builder says give it a year or so to settle. I don't think that will happen, and it would be difficult to repair without a 2/3 or more draining of the pond, and making a big clay muddy mess on the dam that is already grassed.

Sorry to hear that John. I guess you have your answer to why your pond water level is dropping. IMHO your pond builder is dreaming if he thinks the leak will seal itself. In my experience, when water finds a path to flow, the leak gets bigger over time not smaller. Good luck with the Soil-floc. I would get it applied ASAP before the leak gets bigger. Hope it solves the problem.

I plan to make a floating PVC rectangle about 2.5 x 10 feet to help to contain the Soil-floc to the area I need to treat. The consultant at Aqua-Ben suggested throwing some of my native clay or Bentonite in granular form on top of the two parts of the polymer to help it sink more quickly into the localized area.

My opinion on seepage (for what little it is worth) is that if water is actually flowing to a degree it can cause erosion, then yes the leak will only get worse. But if it is a very slow seep, then particles in the water could potentially "clog up" the flow and seal it (over time). Particularly if there is a lot of suspended clay in the water to provide for sealant.

That is kind of the philosophy on radiator stop leak. A very minor seep it will often stop. But something flowing has little chance. I would imagine the soilflock operates on the same principal.

The other thing that will happen over time is that a dam will "settle". Local NRCS guy when he designed our dam put in a figure for this in the dam height calculations. In other words the dam was designed a little higher just to account for it to settle. But he also told me that with the way we were compacting the dam the amount it settled would likely be less than he calculated or maybe even nil. Point is, as a dam naturally settles, it also compacts somewhat.

Just an opinion. No scientific proof or references.

There is a robotic vibrating sheep's foot out there. Controlled by remote. It is about 4' wide. Used for compacting soil. if you are able to re-dig the trench, you should be able to add clay in layers while compacting as each layer is added. I am no expert but I have seen one work to pact soil. I would think it would have to be tied into the original core in the dam. Might be a lot easier to contact TJ for his product.

Tracy

I have the Soil-floc on hand (55 pounds), but it has been too windy to try applying it. The consultant at Aqua Ben (Sandra) said not to try applying it in any wind at all. I bought some concentrated blue pond dye at the Farmer's Co-Op today and poured it around a few feet out from the edge in the areas where I suspect there could be even a small leak. After four hours, no coloration has been seen on any of the clay at the toe of the dam. I will check again in the morning. I have been losing about 3/4 inch of water a day since the flood.
To help with the application of Soil-floc to make it more precise, I made a floating enclosure that is 10 feet long and 2-1/2 feet wide from 3 inch thin wall PVC. About 10 ounces of soil-floc is needed for each move of the enclosure, five ounces of each part. The sequence will be throw one third of the part A, one third of the part B, then a handful of granular Bentonite to help with sinking, then repeat with the next third of the enclosure. I think all the leaks are in the dam, since they did not start until the water reached past the base of it.
After using the enclosure for Soil-floc, it can later (in spring) be used to prevent floating fish food from drifting.

Enjoyed meeting and consulting with John for a spell the other day and providing all the direction possible. I suggested he contact Aquaben directly as he was inquiring on pricing of half units which I have never dealt with. Hope the project goes well for you John, and keep in touch regarding your results. I'm a phone call away if I can help in any manner.

No dye seen outside the pond this morning. Amazingly, the seep through the former ditch through the dam has stopped. I wonder where the water is going? Could the clay filter out the dye?

Whenever we've done the dye test and we were in the source of the leak the colored water appeared. So in my experience the dye was not filtered. It's possible your leak is in another area, or that there are more than you suspect per our conversation. Origins of water leaks are tricky to determine often times. I'd treat the area of your highest confidence and measure the leak following application to determine results. If nothing happens, you may need to reapply in that area or consider full pond treatment as the leaks may exist elsewhere, per our conversation.

I ended up dyeing the entire pond, no colored water yet seen. I will keep checking.

One way to check.

Take a bucket of water from the pond, pour it on the ground slow/fast enough to mimic the size of the stream of water that is leaking out. See if you can see any dye in that water.

If you can, it's most likely not water from inside the pond that is leaking into that particular stream of water that you are seeing.

My WAG? The dyed water in the pond isn't dark enough to see the dye when it's in a smaller volume of water.

You probably wont be able to see it unless you are using an enormous amount of dye or using the dye that is designed for leak detection. (the bright green stuff)Take a jar of water from your pond and you will see the dye is almost clear. The reason it looks darker in the pond is because of the depth(amount of water you are trying to see through). I tried the same thing you are and I know the water is making its way to a certain spring because I just drained the pond in the fall and it stopped. could never see the dye. However I did find a better way to detect. My pond has a ph of about 8.8 all the springs on my ground are around 7.5 (neutral)except for the one where the pond water is going. It has a ph of (guess?) about 8.8. Might help you determine if it is actually pond water you are seeing.

Jar of water from pond looks light blue. Jar of water from behind dam looks clear. I used a substantial dose of dye.

The situation is, my neighbor to the west has a 1/8 acre pond; the east side of his dam is about 60 feet west of mine, top to top. He has enormous (24 inch plus) cottonwoods and ash trees growing on his dam, and one 18 inch ash at the east base of it. His pond drops fairly rapidly after a big rain. I can't tell if the water is coming from my dam or his. I suspect his, or it could be a combination.

Will he let you dye his pond? If not can you find a difference in water from his to yours? In my case the ph was different enough to confirm where the water was going. It did not help me find the source of the leak though. I completely drained it last fall and cleaned it out. When it was drained the spring almost completely quit, where as before it ran about 10 gpm. When I was scraping the pond and cleaning the muck out I did locate a sand vein about 1/4 inch deep by about 25 feet long. I noticed it because as I was scraping I could see certain areas where the dirt would just kind of slide off the dirt below it. Have yet to see if it fixed my problem and will probably try the soilfloc TJ has if not. Hope this helps and good luck. I have been dealing with mine for about 5 yrs off and on when I have time and it can be very frustrating.

I am going to try Soilfloc too, if the wind ever stops. I already have 55 pounds of it on hand. If that doesn't work, the pond project will be abandoned, as I have already put too much into it. There are enough other ponds and public waters near here that I can fish that after a point it is not worth the effort.

Wow John, I'm sorry to hear you are even considering abandoning your pond project. Hopefully the soilfloc will do the trick.
My pond filled again a few weeks ago. I was up there yesterday, and it had dropped 3".
Slow enough that I am not going to drain it, but still fast enough that I'd like it to stop.
The last time I talked with TJ, I got the impression that you should not use the soilfloc, unless the temps were in the 50s. I thought I should just wait for spring.
You might want to double check, just to give yourself the highest chance for success.
As far as my leak is concerned, I think the seep I'm seeing behind the dam isn't enough water to to equal my water loss, I think I must have water dropping into a subterranean level, that I just never see.
I sure hope you get your leak fixed.
Jeff

The consultant at Aqua Ben (Sandra) said it is OK to apply Soil-floc as long as there is no ice on the pond in the area it is applied. It has to sink.
I have worried with this pond long enough, and spent enough. If the wind ever becomes completely calm and allows me to do the Soilfloc treatment, and if the treatment doesn't work, then what else is there to do without spending a ton of money?

I agree. If I can't get mine to hold water, it'll be a big food plot in a few years. I hoping it'll hold at some level. Either that, or hold out for a lot of rain.
I'm not investing the same amount again.

Mine has now dropped 12 inches since the big rain (19 days) We have had 0.6 inches rain since then. Still no dye showing outside pond, but within a few hours after I applied the dye, the seep through the site of the former drain ditch stopped, and now is only a damp spot in the clay. The dye somehow flocculated the pond fairly well, but have lost 1-3/4 inches of water in the three days since. Curiously, the new 4 ft deep minnow pond right above the main pond has only lost about 1/2 inch in the same 19 days, and it was built using only a small dozer and backhoe.

Pond dropped three more inches in eight days with only 0.2 inches precipitation. I still have not used the Soilfloc due to endless wind. Hopefully we will get more rain, and I can apply it to a fuller pond. It's too cold to pump from the creek these days, as my pipe is not buried, and my pump is gasoline powered, thus has to be run out in the open. No dye ever showed outside the pond.

Sounds like the leak might be slowing. If it was getting worse, I would be worried. If it is slowing it may indicate suspended particles in the water may be clogging up the leak slowly, which would be a good thing. If outflow was increasing, that might indicate erosion was taking place which would be a very bad thing.

You might also be getting some settling of the dam helping things.

Hopefully the Soil Flock will finish up taking care of the problem leak.

No wind late this afternoon. I put down a small amount of Soilfloc (about 3-1/2 pounds), with each throw of Soilfloc followed by a handful of bentonite as instructed to help the polymer sink. I only targeted the specific areas I suspect of seeping. It is wait and see now, and maybe do some pumping if the weather warms enough.

After multiple spot treatments involving use of about 10 to 12 pounds of Soilfloc and 50 ponds of bentonite, I have managed to reduce daily water loss to about 1/4 inch. I managed to stop the seep in the former ditch through the dam a few weeks ago, then have worked on other suspected leaks. Hopefully, after more rains and inflow of a little more clay, the remaining minor seeps may stop. If not, I have more Soilfloc. It's very hard to find an application window without wind. BTW, the pond has a visibility of over four feet without use of alum.

John,
Great news! Sounds like the soilfloc made a positive difference. I will be doing a similar application this spring.
Just curious, how did you identify suspected trouble spots for treatment? I have a similar leak, drops less than an inch per day, I can see where it comes out at the base of the dam in the old ditch bed. I suspect the best place to treat it would be where the water side of the dam transitions in to the actual bottom of the pond, but without any dye info, it's just a guess.
Good job so far. Have you pumped it back to full? Up in my part of Missouri, we haven't seen any significant moisture since the 1st of the year.
Jeff

Jeff,
I targeted the areas opposite damp spots behind the dam, trying to get the Soil-floc to sink at the junction of the dug out part and the dam. As suggested by the Aquaben consultant, I would throw Part A, then Part B, then a couple handfuls of granular bentonite on top to help it sink, since I was targeting spots, not the whole pond. I may have to do more treatments. I have been pumping enough to keep the pond from going low, but now the creek is starting to dry up. No significant precipitation here in about seven weeks.

Update to an old thread:
I kept the 1/4 acre pond high through most of the summer by pumping, then after July 31, I couldn't pump any more due to the creek drying up. The pond continued to go down about 1/2 inch on average a day until it lost about 22.5 inches, then it seemed to be all evaporation. In total I lost about 34-1/2 inches of water, but only 12 inches between Sept 12 and Dec. 24. So, about 1/2 inch a day for 43 days, then less than 1/8 inch average per day for the next 103 days. After the rains on Dec 24 and 26, I pumped 25 inches of water into it. Since then, it is down 3.5 inches in five days (about 5/8 inch per day). I have checked everywhere. No damp spots on the back of the dam, no wet spots in the closely mowed field behind the dam. Could it be that hydro static pressure is pushing water out through the bottom until it reaches a certain level, then it stops leaking at that level? (pond is 11 feet deep when full, got down to 8 feet deep) If it was leaking into the soil at the relatively undisturbed side of the pond above the dam, then my minnow pond just ten feet horizontally and 6 inches vertically above the main pond would leak there too, but it doesn't. Have used a half unit of soil floc late last winter/early spring around the base of the dam, and not much changed except a few damp spots dried up. While the pond was down, all the soft clay above the water shrank and dried, and I thought the leak would stop, but it hasn't. The pond is in all red/gray clay; very little rock. Still hoping it will seal sometime, but pumping when I can is a whole lot cheaper than a full soil floc treatment. Edit: I determined in August that the water that used to be behind my pond was coming from the neighbor's pond, not mine. His pond dried up in the drought, and the area is completely dry now.