Pond Boss Forums POND CONSTRUCTION Building a dam How Can I make a core trench for a creek dam?

Hello all, This is a great web site! I'm glad I found it.

Ok here we go. A little history first. I have a 30 year old swimming pool that used to draw water from our creek 75 feet above. Long story short the dam busted and we decided to have
a pool liner put in. Then the pool liner broke. Five years later we decided to build another dam and use the pool as a pool and pond, we want our old freezing cold swimming hole back.

My question is how can I build a core trench for this dam. I'm thinking of digging a trench 2 or 3 feet in front of the dam
Maybe a 1 foot wide by 1 foot deep and fill with the proper type of clay and then cover with liner and heavy rocks.

We only need this dam to hold back about 12 to 14" of water to get our 2 inch pipe submerged and feeding the pool. With 12 to 14" of water we will have about 4 inches of slope per 75' to the pool for our gravity feed.

Here are 2 pictures, first the creek dam (about 15' wide and only holding back 2 or 3 inches now), notice the rusty piece of pipe at the bottom of the picture (that is where the water inlet will go) and the second photo is the pool below the dam (upper right hand corner of pic is where oulet is)






I have a lot more work to do with getting more rocks & concrete for a solid structure to hold the water. But I'm working at it
as I can.

Thanks everyone for any input,
Rusty

Anyone?? -Bump-
Tx,
Russ

Hi, Russ. When you say the dam busted, are you talking about the rock lined structure in the top picture?

Hi Bruce,
Yes that is correct. The first picture is the stone dam that
I have repaired. This small dam will feed that old swimming
pool in picture 2.

I want to use clay to seal the front of the small stone
dam then use the rubber pond liner over the clay to get
the creek high enough for outputting water to
the old pool. Any input will be appreciated
on do's and dont's.
Thanks!
Russ

Do you have access to any heavy equipment?

Do you own the property just below the existing structure, and have you considered building a new dam just above or below the one you have? Just wondering, because it seems like you'd have a muddy mess working on the existing structure.

No access to heavy equipment. But we own below and above by 300 feet each way - I do plan on building a dam above and route the water thru flex hose thru my dam (I will be putting a 6"
steel pipe thru the stone dam)
Thanks for your response,
Russ

There's a new book out, called "Perfect Pond-Want One?", and I think it addresses a lot of the issues in regards to core trenching. I couldn't core trench my way out of a wet paper bag, but without heavy equipment I'd think you'd have to have a fairly dry field. Backhoe, maybe?

RustyFisher,
Do you really need to core it? If it wasn't seeping out of the the dam before or now you might just want to rebuild the dam.

Thank you Bruce for your input and zhkent as well.
I'm thinking I'll get the book first and then
rebuild it the best i can. Agian thanks fellows.
Russ

What about disassembling the rocks, then rebuilding with a mixture of smaller and larger stones, and incorporating some quikcrete? This would at least slow the seepage to a point where there would be a bigger pool of water. Then you could just backhoe the basin to get the old sediment out.

Lbuck,
Yea thats what i'm going to do. I dont need to dig it any deeper what I need to do is make the water level higher so It can feed my pool. So really it will only be say 14 to 16 inches deep when I'm finished.

The small and big rock and quickete is a great idea. That will hold it together nice my only concern is making it hold water ie: using clay and a small liner that goes up and over the dam then cap it nice with flat stone set in concrete
for a natural look.

Thanks for the input!
Russ