Pond Boss Forums GENERAL QUESTIONS Muddy water Drain it to clear it?

First post.

I have a 3yo pond that has suspended clay. It was caused from building our house above the pond. I not only have a clarity problem I also have a leak. My question is this. If I drain the pond to deal with the leak will the suspended clay problem be gone when the pond fills back up? I now have thick vegetation all around the pond which was not the case when the problem started.

Thanks!

Alum Kicks Clays Butt


Start here. LOTS of great info here.

I’ve done the alum and it worked real well. However, I didn’t have the needed vegetation and the suspended clay problem came back. Since I will be draining the pond I am wanting to know if that process will also bring the clay to the bottom and it will not re-suspend or will I have to treat with alum once it fills?

It is hard to see due to the functions of the Forum, but Boondoggle posted a link to a very lengthy thread discussing the best way to clear ponds where the cause is suspended clay particles.

Questions:

Are there any aquatic creatures in your pond that stir up the sediments? For example, grass carp and other rough fish, koi, bullheads, crayfish, insect larva, and a few others not mentioned. Also non-aquatic creatures such as humans or dogs swimming, diving ducks eating, etc.

Does it get worse after rain storms and then slowly get better over the next week?

Is it seasonal and you can notice a variation over the course of the year?

Your next step is to perform a "jar test".

You need two decent-sized jars (preferably glass). Fill each jar about 80% full. Put one in a dark place (closet) and one in good indirect sunlight (like a windowsill that is NOT in full direct sun). Observe both jars for a week.

If both jars clear up in a week, then you probably have a mechanical turbidity issue. There should now be material at the bottom of your jar. Some organisms in the pond are stirring up sediment or debris to make the water murky. I could even be humans, dogs, etc. as the organisms.

If the jar in the dark clears up in a week, but the one in the light stays murky or colored, then your murky water is probably due to a phytoplankton bloom. The photosynthesizing organisms died in the dark.

If both jars stay murky for at least a week, then you probably have suspended clay particles causing the murky water, and you will need to treat the water to change the ionic balance.

The solution for each problem is different!

[Much of that "jar test" advice above is from an old post by teehjaeh57.]

Jumping WAY ahead to your current questions. Yes, the clay running into the pond before you had ground cover over your bare yard certainly could have worsened the situation if the problem is suspended clay. Is the pond significantly older than the house construction? Was the pond clear after it filled, but before the house construction? The reason I ask is that if clay from your yard is the problem, then similar clay is almost certainly in the sides of your pond.

Your current vegetation will help reduce the problem in the future if you can correctly treat your pond to get it clear.

P.S. How bad is your leak? There are many threads that discuss possible solutions to leak problems depending on the pond situation.

Come back after performing your jar tests and post the results. Also, add some more information about how your pond was constructed and details about the water source and the characteristics of the leak and you can get more help on that too.

Good luck on your future pond fixes!

Dang it! I typed a long post while you typed a short post.

My post above is in response to your original post.

What are you going to do when you drain the pond?

IMO, settled clay on the bottom will probably go back into the water column after you re-fill the pond.

If you are going to disc the pond sides and bottom and then bring in compaction equipment to stop the leak, then I think most of your old suspended clay will stay put after being moistened and compacted.

7/8 acre pond. 12’ deep. Lmb, bg, yp. Water clarity never changes. 6” or less visibility.

The dam doesn’t seem to be the source of the leak. I fear I have a backward running spring. I will tackle the leak when I figure out exactly what is causing the problem. I have considered covering the pond in bentonite clay once it is drained. My thought is the bentonite would keep the suspended clay from resurfacing??

The pond is the centerpiece of our new houses landscape. The driveway winds across the pond dam and we are the last house on a dead end road. However, my frustration may cause me to simply drain the pond and have a contractor doze the dam. I would rather have more grass to mow then an almost 1 acre mud hole.

Appreciate the reply’s.

Sorry about the leak. If you are considering removing the pond, then I think fixing the leak needs to be the #1 priority. I would be sad indeed to have a house overlooking a pond and then have to lose the pond.

Do you have enough watershed (surface area) that will direct rainwater into the pond? If so, does your pond water level go up after good rains and then subside rapidly over the next few days? Does it usually come down almost to exactly the same elevation?

A spring in the basin of a pond will act as either a water inlet or a water outlet. For a well-connected spring, the water level in your pond will always equilibrate to the "potentiometric surface" of the spring. (That is the stabilized water level if you dug a hole down to the spring and then measured it the next day.) On my farm, the water level might only go up a foot above the spring horizon, but in some places it can be as great as 8 feet.

Were you on site when the pond was constructed? When I dig on my farm, it is easy to see when I reach the level of the spring in the side of the trench. The water starts seeping, but I can always see where the clay overlies the sandy streak that is the horizon of the spring. Sometimes the sand layer is only 1" thick, but still produces prodigious water. Sometimes the sand layer is several feet thick and I have to quit digging before getting through because my trench is collapsing.

I do not know if the spring would be visible in the side slope of your pond. However, if you can completely drain the pond, then I think you may be able to locate the spring horizon if you get hot, dry weather so the rest of your pond basin is no longer damp.

If the spring is high in the side slope of your pond, then it MIGHT be possible to save your fish in the remaining deep pool and fix the pond with some bentonite and compaction equipment. However, it is very difficult to run your heavy equipment with water (and slick clay) in the basin.

There are a few success stories of sprinkling bentonite and it migrating into the leak and then swelling enough to stop the leak. However, there are some commercial products that are usually even more effective for that application.

There is a member on the forum that does free consulting on pond leaks with the handle of teehjaeh57. (He also sells a commercial solution, but is very willing to just give expert advice to people with leaking ponds.) You can search for his handle and send a private message or email him at tj@innovativeprops.com. He may be very busy right now due to all of the current pond activity.

If the application is feasible, you might be able to apply his product in your pond with the existing water and fish and either stop or significantly slow the leak.

If that is not feasible than you can probably still seal your pond the "old school" way. Drain it and let it dry. Hopefully you can see the spring inlet/outlet horizon. Disc or tractor rototill all of the pond slope or pond bottom where you observe the spring, plus a wide "safety" margin. If you have good clay, you can then use compaction equipment and moisture to seal the spring horizon that you just disrupted. Scrape up some additional clay from the bottom of the pond and put an additional 6" thick compacted clay blanket over your spring.

If you do NOT have a good clay in the pond basin (or nearby), then you could add bentonite after the disc/rototill step. Then do your compaction. You then need to mostly re-fill the pond in a single step. Any good water source? If the bentonite and clay seal goes through repeated cycles of wetting and drying, then it can develop significant cracks.

Hope that adds some more information for you to process on your pond plans.

My understanding is that the alum treat is a long term fix as long as there isn't new clay that is entering the pond. The bottom may get stirred up from time to time but the existing clay from the original treatment should still have that clay bound so that it can sink to the bottom over a few days.

If there is still clay entering the pond from runoff, critters, or wind/wave action after the treatment.....those particles would have to be treated as there is nothing to bind them to.

Sadly I don't have much personal knowledge as my total experience is from reading and my one test on a 2+ quart bottle for an upcoming treatment. Would love to see some other feedback though.