Ground water issues -- possible solutions?

[Mmathis]

The pond is going into it's 3 season. Knowing what we know now, probably would have addressed the drainage issue BEFORE we built the pond.....or maybe not.....who knows what you'll do when you're impatient

Currently the pond is "down for repairs/renovation," to address the consequences, and hoping/praying that our drainage issues won't affect the pond anymore, but would like to come up with a viable solution as this is maddening. And I think we actually have the pond placed where it impedes natural drainage [whatever that is in heavy, clay soil].

Anyway, we have a lot of ground water seepage. When the pond is naked [no liner], there are a few places that actively collect water AND you can watch the water weep from the walls. But it doesn't do this everywhere, just in a few spots. It seems to start around 2 1/2 ft. below the surface. And some places are worse than others...... It rained a week ago, and I still have to go out every morning and pump water out so I can work [again, the pond is naked right now].

• Just to clarify, we DON'T have a problem with run-off and there isn't an issue with water getting behind the liner due to surface water -- believe it or not, the surface water drains pretty fast.....straight down into the clay which then becomes saturated. And the only time there has been a problem with the liner floating [knock on wood] was once when we had the pond drained down. That's also when the walls collapsed 'cause the water wasn't there to hold them in place.....
• I was thinking about adding either a French drain, a dry creek bed, or a combination of both, on either side of the pond but there are space limitations and just HOW DEEP would I have to dig? And maybe I'm being a pessimist, but I'm not even sure this would help anything.....
• Another concern has to do with 2 of the trees in the yard. One is dead [that's approx. in line with one of the worst seepage areas] and we're going to have it removed as well as one next to it. Since tree roots soak up water, what can I expect once these are removed....worsening drainage problems? [well, since the one tree is dead, it's apparently already contributing to the problem]
• At one point, we thought about digging a sump hole and sticking a pump down there periodically, but somehow that doesn't seem the right way to go.

See my drawings....

The first one is a sketch of the back yard. The "X's" around the pond indicate the spots with the worst seepage. I drew a few black arrows to show the direction/path that we THINK the surface water takes. The 2 trees with white "X's" are the ones we're eventually getting cut down. The width between the pond edge and the 1) giant rock, and 2) turtle habitat is only 3 or 4 feet.

The 2nd drawing shows about the depth that the ground water seepage starts. From the walls, water weeps; on the floor, it pools.

Any advice or encouraging words?

 

[Big Lou]

I found this on the web. It's about groundwater seepage into a liner sided pool. Maybe it will give you some ideas. Suggest you read all posts.

http://www.troublefreepool.com/threads/40065-Removed-Old-Liner-Water-Leaking-IN-to-Pool

 

[Mmathis]

I found this on the web. It's about groundwater seepage into a liner sided pool. Maybe it will give you some ideas. Suggest you read all posts.

http://www.troublefreepool.com/threads/40065-Removed-Old-Liner-Water-Leaking-IN-to-Pool

Thanks, Lou! I thought it was quite interesting that in my case, the one solution that I thought was the dumbest [sump hole] is exactly what they recommended -- or a variation, anyway -- they called it a "well point," I believe.

 

[Big Lou]

Hope this gets you started on a permanent solution.

 

[herzausstahl]

Do you have a wide photo of your yard showing the slope?

 

[Mmathis]

Do you have a wide photo of your yard showing the slope?

No, not really. To look at it, it looks flat.

 

[herzausstahl]

Clay holds moisture like crazy, I wonder if it's weeping out in the hole since you are providing it with a lower place to go? You said you never had a problem with a liner in place, did the water pressure push down on the liner forming a greater path of resistance as the water is absorbed deeper into the ground. No liner, no resistance and it's weeping out on you. So if it didn't affect the pond before do you need to worry now? I have all clay and have to be careful in some circumstances due to frost upheaval but I doubt you have to worry about that. So if you had no problems before you removed the liner, go with it. Otherwise if your worried, put French drains (or even a trench filled with gravel covered by topsoil) around the pond leading to a gravel filled pit for it to collect and be absorbed by the earth.

 

[Mmathis]

Clay holds moisture like crazy, I wonder if it's weeping out in the hole since you are providing it with a lower place to go? You said you never had a problem with a liner in place, did the water pressure push down on the liner forming a greater path of resistance as the water is absorbed deeper into the ground. No liner, no resistance and it's weeping out on you. So if it didn't affect the pond before do you need to worry now? I have all clay and have to be careful in some circumstances due to frost upheaval but I doubt you have to worry about that. So if you had no problems before you removed the liner, go with it. Otherwise if your worried, put French drains (or even a trench filled with gravel covered by topsoil) around the pond leading to a gravel filled pit for it to collect and be absorbed by the earth.

You know, it's funny how sometimes you don't think about the obvious. If you don't dig a hole, you'll never have to worry about having a hole that gets filled with water!

Nathan, you are a genius -- I never really thought about it that way, duh! Pond is going into its 3rd season. Have never had an issue with liner-float [one exception -- see below] in all this time. The water level is normally kept right at ground level, so yes, the hydro-static [?] pressure of the water is preventing that seepage from happening. And yes, the only time I see the water seepage is when there is no liner and it's bare dirt. Again, DUH!

....and, the only time I have had liner-float was the one time I had the water level down for an extended period during work, and we had some good rains, which equals reduced hydro-static pressure from within the pond, so.....

So, if French drains & dry creek beds tend more to deal with surface water run-off, which I don't have, I just may rethink that issue. You have just lightened my load, Nathan!

 

[herzausstahl]

You know, it's funny how sometimes you don't think about the obvious. If you don't dig a hole, you'll never have to worry about having a hole that gets filled with water!

Lol no problem. Case of a new problem is introduced and you feel you need to solve it before figuring out why it's occurring. I do this all the time, especially when I design something new since I always try to figure out all potential problems while designing something and then troubleshoot/solve problems I miss as they occur. Clay I just happen to know since I hit it 6 inches down or so once I dig below the soil they replaced when they scraped the lot to build my house. But it's just all over which is interesting since I live pretty much on the top of the Niagra escarpment in my area. Good luck with the redo tho!