Pond overbanking ideas !!!

[builder2]

Hi all.. I have a small pond that I need ideas on what I need to do to make the outflow look good and be functional. Size is 30' by 90' by 20' deep.. Things I have tried.. #1 pipe underground with a standpipe coming up into the pond just below the ponds banks.. 泥idn't work for long after 3 years of ice lifting the and pipe being pulled up and down it broke.. #2 Last year I just let it run over the bank and off into the woods.. 泥idn't work This spring it washed out the end of the pond.. Not bad but you can't get the tractor over it,, I dumped some large bolder in it for now but want to make it look good..

What I want is a spillway that can be driven over by the riding lawn mower and tractor.. I was thinking about digging a V shaped trench away from the pond.. put heavy fabric down then fill it in with small stone ???

Hi,

Our pond has been in since 94. We have a 12" corrugated metal tube for the overflow.

It extends about 2' out from the bank towards the pond.

When we installed it we poured concrete anti-seep collars on both the inlet and outlet sides. This held and did not leak until last year when I noticed water was leaking out belows our tube.

The way I fixed this leak was with Bentonite. I bought a couple of bags from my well driller (it is used as a sealer while drilling). I poured the dry granules as the water was flowing around the tube and worked as much as I could down the channel the water was leaking thru with a long rod. This stopped the leak in 10 minutes. Then I banked and packed more in all around the tube where it met the bank. I have had no leaks since.

Bentonite expands to about 10 times its size when it comes into contact with water. I had previously used it on another leak where an old field tile went thru the bank with good success.

Our overflow is about 2' under the bank and we drive/ mow all the time over it.

Hope this helps as I now that pond leaks are discouraging.

Paul

 

[Ken45101]

If you are going to do a pipe, it should have a large collar around it in the middle so as to prevent leakbye.

Another approach is to cut the overflow in a location away from the dam. Cut it in undisturbed soil and preferably for a fairly long distance. That will erode a lot more slowly, especially if you line it with rock.

Another thought would be to reduce the volume of water flowing into the pond if you can do that. Of course for many ponds, that's impossible.

Ken

 

[hr3]

Thanks Builder but I can't go with pipe,, It would have to be down 4' to keep frost from moving it and I want to keep the pond as high as I can,,,

Any other Ideas,,, ???

 

[schmism]

you have to drain the pond to do this.... but it is the best method.

- you remove the dead stagnate water from the bottom of the pond
- dont have problems with sticks/leaves/debris entering pipe
- dont have problems with ice
- dont have to look at the outlet pipe

 

[Ken45101]

Unless you have an air vent at the peak of the pipe, I think it would act as a siphon and drain the pond every time it overflowed.

Ken

 

[schmism]

the idea is the pipe is never 100% full if its designed right. as such there is no suction created.

On a new pond that type of overflow is common in my part.

 

[Ken45101]

the idea is the pipe is never 100% full if its designed right. as such there is no suction created.

I guess that makes sense if it is a large pipe (size is not shown in the diagram). But a smaller pipe or one with heavy water flowing might start acting like a siphon, I would think. I guess your "if its designed right" is very critical

 

[hr3]

Here is the pic,,, The big rocks I put in there when we were trying to haul wood out just as the snow was melting,, They wil be coming out as soon as it dries a bit more,,

 

[wvpolekat]

the idea is the pipe is never 100% full if its designed right. as such there is no suction created.

On a new pond that type of overflow is common in my part.

I don't see how it could be "designed right" unless you use an absurdly large pipe, like 24". In a heavy rain event, all it would take is a bit of surge in level to fill the elbow at the top and your entire pond gets siphoned out. Seems too risky to me. The real risk is created by the outlet being so low, it's a siphon waiting to happen.

Air vent or running the overflow at the level you want the pond are much safer options, neither of which would reduce the capacity or other functionality.

 

[20 20]

Here is the pic,,, The big rocks I put in there when we were trying to haul wood out just as the snow was melting,, They wil be coming out as soon as it dries a bit more,,

Thanks for the picture, you can easily use the design I suggested. It is cheap natural and will hold up for many moons. You could also just place a large culvert pipe at you water line, shooting straight through the bank. If you use a culvert then you'll want to screen off the ends so stuff doesn't stop it up.