Help experts! I have a couple acre pond in southern Illinois which is experiencing huge hole on the backside of the dam. I know from reading here before that the grade of the backside of the dam is way too steep....but it is what it is. I think the dam was built in the 30s or 40s.

I'm looking for some advice on how to proceed. I have no heavy equipment, am on a limited budget, and was thinking maybe a makeshift wall where the hole is and then filling it in with dirt.

I'm sure more info and/or pics are required before someone can give me solid advice, but this is just my first volley to see what kind of response I get.

Thanks.

How long has this been going on? is there water passing through the dam.

NightRider
You are correct the big boys will want a picture and more details before they can make suggestions for a fix. The more detailed info you can provide will help

Pat

Thanks so far for the responses. Fortunately, there is no water leaking out of the pond. I have included a few pictures for review. Appreciate any advice.

about a month or so I guess. I do not live on the property and hadn't been out there in awhile with all the snow/ice we have gotten this year. no water passing thru the dam

Thanks. I have uploaded several pics. It may be visible from the pics how steep the back of the dam actually is and how little dam width on the top of the dam as well. I have contemplated adding to the width of the dam by filling in a few feet or so on the front of the dam, but haven't done that yet obviously. I did have a track hoe out there two years ago and fixed some leaks in the dam and replaced the drainage pipe although in hindsight the pipe may be too small as water is normally still flowing out several days after a heavy rain and this year the water level actually went over the dam and ran down the backside. Any advice is appreciated.

MAN OH MAN are you lucky or Blessed. That is the most dangerous NON leaking dam I have ever seen. Most do not make it through in that condition. For my two cents, if you are on a budget, I would pack it from as low as you can where the backside of the dam get solid as close to the bottom as possible, with GOOD GOOD CLAY all the way to the top and widen that particular area/line, from the bottom to the top and pack it every 6" or so with a manual tamper if you cannot afford to rent a gas model. It looks about two foot deep or so so you could easily 4 or 5 layers packed. Then you recover with dirt for the grass to grow and hope it sticks.

As you know it would most likely NOT hold for many rains like that. That is my two cents on the cheap way. Let us know how it turns out.

That tree probably isn't helping much.

The pictures tell a lot. It looks like the water went over the top of the dam.
1 lower the water level
2 get a couple of bags of secrete and build a little dam to make sure water cannot pass over the dam again.

Do you have an emergency spillway on either side of the dam that can be lowered to help keep the water level low until the dam can be repaired?

NightRider
Checking in to keep myself up to date.

How Much drainage does this pond have?
Do you have access to the back of the dam?

Yes the water went over the top...first time that has happened. Is that a couple bags of concrete? I only have one drainage source. A 10" oil pipe. It got clogged with the last super rain we had which caused the flow over the dam

Just one drainage pipe. I have full access to the back of the dam

Thanks for the advice. I'm gunna get right on it

Nightrider, if you are getting large amounts of runoff that your overflow pipe cannot handle, consider installing a siphon system. It is very effective, not overly expensive and makes level control much easier. Holler if you need a hand on the dam....I am in the St Louis area.

Rainman,

Thanks for the advice and i'd be interested in hearing more on the siphon system as well as any advice/help you might have to offer in regards to the dam. If it would be easier, I could give you a call and we could discuss directly.

Again, thanks for your advice.

rex get up there.

Can you get the pipe un plugged? If so do that before it rains.

Nightrider,

I recently had my 4" siphon system plug up and the water started going over the top of my dam with more expected rain on the way.

I was away on business so I had my eldest unplug the 4" pipe that night while I drove back in and the next day I bought a gas powered pump, 158 gpm, accessories and started pumping out the pond before and during the rain that followed. I dropped the 1-7/8 acre pond about 4" before the rain started and was able to remove more than what was coming in.

I don't have any pictures but hopefully this weekend I will get you some and post them, easy to do, real cheap, about $75 to get it in and draining.

Coupe

Can you tell if there is any water coming out of the back of the pipe?

If there is water coming out at all you might be able to push a smaller piece of pipe in from the top or from the back and get the plug loosened up.

The pump is a good idea.

You do not water to go over the top again. I am betting you used up your luck last time.

the pipe is now clear and I have secured a large tarp over the entire area shown in the pictures as a short term assist while I am out of town. I have a pretty good size electric sump that I can put out there and I will do that to bring the water level down .... if I can get some of this pesky rain to stop until I get back in town on Thursday.

Coupe,

thanks for the info. The $75 you mention...what exactly did that get you? I looked on line for gas powered 158 gpm pumps and the cheapest I saw was about $200.

I've cleaned out the entire pipe and am hoping that was the issue. the pipe is only about 12 foot long so it wasn't very difficult to make sure it was clean.

I'm looking at the pump option now and have covered the eroded area with a tarp for the short term to make sure it doesn't get worse.

any idea if I should apply anything to the eroded area before I start tampering new clay into the opening?

Problem is we are extremely saturated in this area right now so I plan on just using wheel barrow, shovel, and tamper to fix the whole and then address the overall issue of overflow.

Yes...I am sure my luck is all used up so this will be my big project starting on Friday when I get back in town.

Thanks for the advice.

I have 2, 2" and 1, 3" pump I could loan you...a temporary siphon is faster and cheaper however in lowering the water level....how much area drains into the pond and how much freeboard is there above the top of your drain pipe?

Rex knows siphons...helped me just the other day with design and strategy.

Nightrider,

The $75 from Lowes got me three 4" PVC - 10' long, 1-Tee, 2 -elbows, 2 couplings. I had a couple more couplings and some additional 10' sections that I made up. I have the pipe coming around one end of the levee with my discharge deeper than my suction. The Tee is on the suction side, I covered it with 1/4" square plastic I bought from Lowes. I used zip ties and covered both tee ends with the plastic netting, put a few old pool poles making an X across the the 4" pipe to secure it to the pond bottom. Works well for for a 4 acre watershed unless the tee end plugs up.

I bought a 2" gas pump from Tractor supply and it was just over $200. For my issue at the time, I wanted to get the water level dropped as quickly as possible before the next heavy rain came in so I had the 4" pipe draining and I was sucking 158 gpm out of it with the pump. It served my emergency purpose......ground was saturated from all the previous rain so I knew the water shed was going to let it come right into the pond.

As Teehjaeh57 states above, follow Rex's advice....I just wanted to offer my experience and my resolution......no other experience with draining the pond down or with siphons.....

Coupe

Thanks Coupe. I had a long discussion with Rex today and learned a lot. He will be out at my pond tomorrow and he and I will build a siphon so that I can get the water level down. Ground is too saturated right now to do much with the dam plus more rain is coming later tonight. I have the eroded area covered with a tarp right now and my overflow pipe is clean and ready for the increased amount of water tonight.

If the dam will hold until tomorrow when we can get some of the water drained away then I will feel much more comfortable going forward.

Thanks for the advice/comments from all and I'll provide an update in a day or so.

You are in good hands, keep us posted.

NightRider,

I am glad to hear you are in good hands.

I know the feeling I had, I am away on business, wife calls at dusk, says its raining cats, dogs, horses, cows, pigs and some other creatures she has never seen before, water is coming over top of levee, eldest sone is on top of levee with a shovel cutting a ditch across the top of the levee to let the pond drain out some........

Yea, heart dropped, fear overwhelmed me till dispair overtook that feeling....Cotton Picker.....that was 2 weeks ago, I am still getting after shocks across my heart....

Coupe Deville
Waxia Bayou Louisiana

Night: I don't know where you are in Southern Illinois, but I live in Fayette County. Rex knows where I live.

I have probably 60 feet of the 2.5 inch green hose, connectors, stoppers, etc. It is in five or six pieces so I often have three or more hoses running at the same time when I lower my pond water level..

You are welcome to borrow it all if we are close enough to each other, or if Rex's trip to your place takes him through Brownstown.

Bing, Thanks for the offer! Night is just east of Mt Vernon. When I got there, water was about 2 feet onto the top of his dam on the pool side with only an inch or less to rise before topping the dam entirely. It took a bit longer to build the siphon than expected, but it's going strong and his level is going down. We also discovered what looked to be a rotted root that is now a steady flow of about 1-2 gpm on the backside of the dam in part of previous repair of muskrat damage in the dam. The water was very clear coming out, so it did not appear to be eroding more and flow/pressure was pretty minimal. Once the level has dropped a few feet and things dry out a bit, Night will be able to get repairs done.

Sorry I have no pictures....Thought I took some, but I apparently took about 10, one second video's instead.....stupid smart phone....

Good work Rex this is the only place on the planet that something like that would happen
Post pictures if possible

Thanks to everyone for the advice along the way and especially thanks to Rainman(Rex) for making the trip and passing along a lot of knowledge throughout the process.

The siphon works great and I have dropped the water level about three feet. The small hole on the backside of the dam that Rex mentions actually stopped after about six inches of water was lowered. I've located the hole on the front side and will take care of it once the ground dries out a bit.

I am making contacts and planning on redoing the dam this year as well as clean off the back of the dam and actually looking at damming up the backside overflow as another pond. Lots of ideas and hope my money can keep up with my ideas haha. Exciting stuff.

I will post pics in the next day or so. Again, thanks to everyone.

good for you, it is hard to beat Rex