Pond Boss Forums POND CONSTRUCTION Selecting a site Dam on creek

I'm having a dam constructed across a creek that
runs thru my property. The creek drops about 12 ft over 1500 ft from a county road. I'm
planning on bringing the water level up to the
culvert pipes below the county road. The creek is quit deep and about 200 ft wide at some points.
The dam will be constructed at a narrow (about 50' wide) location about 1600 ft down from the road. The soil is mostly clay, but the creek sides have a heavy concentration of silted black soil. Can such a dam project as this be core trenched ? Most of the soil for the dam
embankment will have to be pushed from the
silted creek sides. I plan on two 10" pvc siphon
pipes for overflow. Does anyone have info on
creek dams such as I've described ? I talked
to the NRCS people, but they were unresponsive.

Read Mike Otto's column in Nov/Dec issue of Pond Boss. That's exactly what we did, without the worry of a county road.

Squeeky, Sure it can be done if the watershed is appropriate. But, I've seen dry creekbeds go 15 feet deep with a 3-4 inch downpour. If you haven't done this already, get an experienced dozer operator to check topographical maps for your watershed and build accordingly...the last thing you want is a washout. If the water doesn't run over the road, and you match the pipes, you should be fine.

Squeek just a question at the point where you damm over creek bed will water seep under the bed below suface and wash out damm. Or is it at the point where it goes under the road. Maybe suggest a cross core trench in stream bed with clay dowm to desired soil to prevent undermine.

I am new to this forum but have a background in geology and a creek that I am also considering damming. The important consideration here is flood stage and sediment load. With much drainage area at all your pond will overflow the dam. If you install only two culverts for drainage the odds are the dam won't last. Two common dam types are first a dirt dam with a clay wall and an overflow built into a hillside. The other type of dam is like a low water crossing. This is made of cement which allows flood stage water to run over it. This can be constructed in an arced wall or with a road on top and sloping sides. This is best for high rates of water flow with large sediment loads, it allows the creek to scour the sediment buildup in the bed and not silt up.
If you want a culvert to control the high water level you could use it in conjunction with an overflow built into the hillside. The culvert will need a plate of steel welded around it like a big washer. This will keep water from channeling along side of it and the overflow need an apron to keep flood water from washing back in under the dam.

Good luck, my creek has washed out a couple of dams in the last 100 years.