Pond Boss Forums POND CONSTRUCTION Building a dam Types of Dams

I know a couple places where I fee fish the ponds/lakes there have concrete dams where the water just flows over the top. I was wondering if there were any advantages/disadvantages to these against earthened dams. I know the ponds are relatively large, about 30 acres, but the dam concrete overflow part is only about 30 wide. What about price?

Did you find any information on this subject from other sources? I have a site that would look good with a series of 3 dams, with small waterfalls over the dams to the next lake ... so I am very interested in your research. Thanks

Sorry I didn't find anything on the internet. I know I have seen many ponds with the concrete style of dam. Most of the ponds that I have seen them in are fairly old ponds so I'm not sure if this is an old technique used or its just not used very often. I'd like to hear back from some of the pros here on the site and see what they think.

Chris

Concrete dams and spillways are used for high outflows of water and to keep water flowing in a direct path to prevent errossion.We still install them when it is the best solution ,there are many factors that determine their use. Over an existing stream bed and in the olden days it was a quick way to build a pond on flat terrain, such as a sunken plot of land to hold water

Scott

A couple of months ago, I decided to make an attempt at installing a log dam in one of my ponds. Its sole purpose was to increase the surface area for ice skating later this winter.

The dam was working well until a heavy rain this past week. Knowing nothing about the engineering/water dynamics involved with dams, I guess the increased water runoff must of scoured the underneath of the log enough to force it out of the shallow trench it had been placed in. Although the pond has dropped back to normal levels, with a nice 8" "ring around the collar", I'd like to give it another go next summer.

Placement of the dam would be at a point in the outlet that is only 8' wide. I'm thinking of excavating a trench 2' wide, 12' long x 18" deep. In this trench, I'd bore two 6" holes with my post hole auger. Once this is done, lay in some rebar and pour cement. The finished product would look like the "pi" symbol. To increase eye appeal, I'm thinking of laying up some flat stone to give the dam a \_______/ look to it.

I'm hoping the combined weight of the concrete and stone will keep this dam in place. My goal would be to raise the water level 8-10". Lookiing for comments on this approach.

Russ,

Why not just build up the dam with clay? If the add-on is wide enough at the base and tamped down, it will never leak. Adding good thick sod would help prevent erosion.

Would the add-on be the main spillway?

If so, you would have to guard against wash out. A thin layer of concrete, asphalt, etc would be necessary. Keeping the overflow wide and shallow as possible will help prevent washout.

Bob,

Since my property does not have much of a grade, I thought the dam would have to pull double duty and serve as the spillway also. I'll have to shoot some grades and see what I have to work with. Thanks for the response.

tritonvt:
In addition to Scott's comments, see comments under "selecting a site, dam on creek" the geologist had some good insight as well.

JP