Pond Boss Forums POND CONSTRUCTION Building a dam JET..04/09/09..NEW CHALLEGE/PROBLEM/ISSUE WITH Dam

ok, new challenge on new dam.......

the back slope which has a 5 to 1 slope had developed a 10 by 10 foot pit at the foot of the dam area and the area that has sluffed off is approximaately 3 foot deep and very soupy, water saturated.

not sure at this point if dam leaking/seeping or a spring has shown it face in this area. ??

presently this backslope area is @ 30 foot from the beginning of the crown on top which is @ 14 foot wide on top.

cannot trench with hand tools (shovel or hoe ) per too soupy and cannot displace enough to trench and allow water to begin to drain in order in to determine where water is coming from.

have small track hoe scheduled tomorrow morning to trench and allow the water to drain in this area, once drained, hoping we can better discover if dam leaking or a spring has caused this problem.

anyone had this problem/issue come up once a dam has been built and if so what was resolution ??

major or minor problem ..not sure at this point until we get area drained..........

pondbosses........any suggestions or insite on this issue ??

JET
cell phone, 903 391-1772

Hey, Jet. My issue is not quite as evident as yours with the soupy mess and all, but check out my post under the soil questions forum.

Did you build this dam or buy the place with it in place? If you built it, did you put in a keyway? If so, was it compacted and how deep and wide was it?

Was the soil under the dam stripped of top soil? Was the soil used for the dam compacted and built up in lifts? If the dirt was just dumped there and not spread out in thin layers, then it's not compacted and it will not hold water.

If the dam was there when you bought it, is this wet area new? Has anything changed? Did you remove a tree? Any rodents or beavers in the pond? Beavers love to tunnel into the bank if they cannot build a wood home. Levi failure from beavers is very, very common in the SF Delta from SF to Sacramento. I've personally killed dozens of beavers there with friends and can attest to their numbers.

Good luck,
Eddie

I seem to have a problem like this all the time.
Most of the time this is something that you will have to live with.
The expence of working on seepage is not worth it.
Because; more that likely you cannot make it any better.

If there is enough water passing threw dam to cause the dam to fail then it is time to work on it.

ok... we did not core this dam with clay as normal per access is difficult, have constant water supply and contractor said has built dams in this area with constant water supply without clay core and was successful.......

access was a big problem to haul clay in trucks and cost was secondary...

still not sure today if this is springs or the dam is leaking and/or seeping.

the issue that drives me to do something different is a slow loss of the back slope on one side of the dam which is caused by water seepage which began saturating the soil at the foot of the dam on backslope. we have since then brought in track hoe and sloped this area where some of the wter will drain off and get it off the dam soil area.

another backslope section sluffed off today, I got down in this area and see water seeping thru the soil in this area....still not sure if a spring and water seeping thru soil?

contractor wanting to bring in clay in dump trucks and plug/core the dam backslope that is sluffing off to prevent sluffing off of backslope and losing soil...we do not expect the clay to spot thw water from seeping/leaking out and will provide drainage away from dam area but still not sure what to do at this point ??

seepage is small in comparision to water supply and water exit the 12 " siphon via gravity flow but the issue that drives change is the sluffing off of the soil in the area of backslope of dam ?

contractor to meet me monday after noon to observe and make a plan to correct the loss of the backslope of dam... not sure what this means or what it may cost yet... ?

most likely we will use track hoe to dig into backslope more to see if we can figure out if dam seeping/leaking or a spring showing up ??

suggestions/ideas ?

JET

What is the difference between a spring that shows up and water that is forced into the ground and out of the ground inside of your dam? How can you tell if the moistures is coming out of the ground and not along the line of existing dirt and the dam above it?

In just about everything, you can cut corners for so long and get away with it, but eventually it catches up to you. I think your contractor cut a corner on not putting in a key way. I think that he probably cut other corners. Did he compact the soil in lifts? I doubt it. From the sound of things, he dumped the dirt and kept building it up. He didn't install your 12 inch pipe correctly, he didn't give you a keyway, and now he wants to cover up the problem with the hope that it will go away.

It will go away just like every other problem in the world that you cover up. Unfortunately, it will also come back and be worse then before.

Have you made final payment on this? If you still owe him money, hold onto it. You'll need it when you have to hire a different contractor to fix this guys shortcuts.

Eddie

Jet, I can tell you from experiance that you are not going to seal the dam from the backside. At the very least, you will need a 3 foot thick blanket of clay in the deeper pool area and face of the dam and from one to two foot depths as the pool area shallows. All the clay (with the proper water content) should be spread and compacted in no more than 6 inch lifts--4 inch would be better.

Have the local NRCS agent come look at it. Mine supervised the repairs. The agent can also take core samples to see if usable clay is available on site as well---These services are free to use.

Jet; Rainman is right you will not stop the leak from the back from the back.

You can put a fabrick on the back slope cover it with oversized rock and that will slow the sluffing.

You need to make sure that the dam is no danger of failing. If there is enough water passing threw the dam to wash it out, it need to be fixed, now.
otto

04/28/2009, just a update on my Dam backslope sluffing problem,

it appears this may be a spring instead of the dam seeping and/or leaking. When it does not rain, the seepage flow goes down to a even smaller seepage flow and it increases after it rains.

we believe if it was leaking through dam, it would remain constant and/or increase over time but it has done neither.

the sluffing has stopped since we was able to allow the seepage to flow and drain away from the backslope area and exit into the trench that the 12" siphon exits into.

the pond level stays constant and to date no problems with the 12" siphon.

plan to continue to observe daily and may decide to leave it as it is since the dam appears to be holding fine with no visable signs of failure at thiS point.

we measured the normal flow exit 12" siphon and looks like we have approximately 40-42 GPM natural spring water flowing in pond and exit 12" siphon. pond level remains constant.
PH OF WATER is 6.0 ph and remaing constant.

But...have new question on grass for the dam, the rye grass grew wonderful but now it is starting to get brown because of he hotter weather..so I overseeded common bermuda with seeds that was hulled ( without hulls) , fertilized with triple 13 and watered but practically none of it has sprouted and we did this in last week in april so,,, now we must do something else to make growing season....suggestions ?

what grass grows best on a dam in east texas, by the way the ph of dam soil is 6.0 ph.

we only have 4 more weeks for good grow season so we must act quickly.

thanks, JET

Who told you that we only have four more weeks of good growing season?

Bermuda needs hot weather to germinate. We've had some very cool weather this year and the Bermuda at my place is way behind where I would consider normal in growth. I'm just starting to mow it for the fist time this year, and last year, I had mowed it several times by now. I was told by the guy at the seed store that I needed the soil to be 80 degrees for the seed to germinate . I'm getting there right now at the peak of the day, but I'm also dropping down into the 50's and 60's at night.

I planted 2 acres of Bermuda seed two weeks ago. I don't expect to see anything out of it for another week at the earliest. When it does sprout, it will come out as a very fine, thin blade. It will stay like that for few weeks, then start to bunch up into a sort of island of grass. Once that thickens up, it will start to spread out.

Eddie

sorry Eddie,

what I should have said was May and June is suppose to be the best planting times for Bermuda based on everything I have read.

it probably has been too cool, especially at night but I am concerned just in case the seeds do not germinate.

I did not lightly disc or sratch up the existing grass or dirt surfaces since the rye was doing so well, I simply overseeded the rye with 50#'s of common bermuda, fertilized and some water, also got a little rain.

sounds like you think it may still sprout once the temperatures get right day and night.

right now, I have a water sprinkler going and move it every hour to next spot.

JET

I think you should be fine. It would have been better to cover the seeds, but the water will do that for you too. Mother Nature doesn't till the ground to spread seeds, so your method is just more natural then mine. LOL

The only other consideration is if your soil will grow Bermuda. Since it grew Rye, I would think it will grow Bermuda. You can always do a soil analysis to find out for sure what the soil needs and work on improving it. Mine was pretty bad since I had removed all the top soil and dug down several feet over the entire area. I wanted to field to catch and divert water to my pond!!!!

If you're curious, I have a thread going on it over at Tractor By Net. http://www.tractorbynet.com/forums/rural-living/142586-creating-my-pasture.html

Eddie

Way to go Eddie