Dam Repair

[bcnu]

I have a pond with a concrete spillway - 3' across that we use for irrigating the garden. I use 2x4 and 2x6 to dam up the water. Here's the problem: there is a small pocket of concrete that has eroded, right where the spillway meets the bottom board. It's small, just a small scoop but water runs under the board. Also, I am getting some seepage under other sections of the bottom board. Not a lot but the stream dries up in the summer and I can't afford to lose any water. Nothing I've tried so far seals the bottom. Any ideas? I saw some spools of stove gasket and wondered about stuffing it along the bottom board but I'm sure it would allow water thru sooner or later...probably sooner. I'd like a quick fix for now. Later I might try a small pond liner to extend a ways in front of the spillway and that would go up the boards - usually 3 or 4 2x6 high.

 

[pinewoodburner]

The small pond liner will probably be the best fix. Any small seepage usually will get larger and larger. Try and get is stopped asap.

 

[Adios Pantalones]

Concrete piers etc are poured directly in the water and harden. You would need to clean out/chip the bottom out of that hole first, possibly with a temporary retaining wall to hold the water back (or drain off the pond to that level if feasible).

 

[burntime]

sand bags to hold back the water, pour it and fogetaboutit! In a day it will be solid and it will cure slowly when the water keeps it cool. Another possibility is aquaplug...its a water submersible concrete as I understand it. Builders use it where your water lines come in underground for your home. Just a thought.

 

[bcnu]

I won't be able to get all the water drained away from area this summer as just enough water flows in, even with all the boards out. I tried sand bags , both full and partially full and still had some water getting thru. A friend mentioned bentonite which expands in water. I'm going to try and create a diversionary dam to get the area as dry as possible. Fortunately, we just started planting our garden, 25x100, and have rainy weather for a few more days. Thanks for the ideas.

 

[jawquin]

You don't have to have the area dry. The flow of water should not be fast to use hydraulic cement. It sets up in 3 to 5 minutes. I believe aquaflow was mentioned in an earlier post. You can get the fast curing, expanding cement at your local large outdoor and building supplier. Here is a link with some ideas of the stuff. http://www.doityourself.com/icat/hydraulicrepair

 

[burntime]

Just checked in again, jaqquin is right, you just can't have the water rolling thru, a little flow is fine.

 

[bcnu]

Appreciate the link. I've made progress in slowing down the flow. The pond is filling and I'll check for leaks again today.

 

[bcnu]

a quick dam update and thank to all(the link to hydraulic cements was helpful). Found a source of bentonite at a local well drilling company and also found another leak in the earthen berm. It will be easy to use the bentonite on it. I've been able to seal up most of the original leaks and the pond has more than doubled in volume and that should get us through the summer months. This fall I'll drain the pond and make more permanent repairs.