I have to replace the dam on my pond, after maintaining the old one for 20+ years. The dam is concrete over earth, and the April floods caused a top-to-bottom crack in the concrete part, and now a whole section has shifted.. I can get some $ help from the vol fire dept, because they created an area to pump water from a few years back, and rely on the pond for local fire protection.
Back then, they drained the pond with huge pumps in order to dig their holes and line them, so I suppose that's the best way to allow for a pour once the old cement is pulled out.
I just don't know much about this, and haven't been able to find an engineer locally who know a lot more than I do.
The hydraulics are this: The pond is about 1/3 acre in size, with an average depth of about 5 ft, and a pocket that goes down about 15 ft. It's fed by a brook that floods with rain, and never, ever goes dry. Also,spring water bubbles up in three different areas. It was originally dug out and dammed around 1950 as a swimming hole for the then owner
When we moved here, there was a local source of clay: a brickyard, which has since closed up. I could patch leaks with that clay and, believe it or not, brown plastic bags.
I can get an idea of the original construction just from looking. The lower dam is boulders and dirt, probably clay, and the concrete was poured on the uneven surface of the rocks. The uneven area at the bottom is where I did a little patching every year.
The concrete portion is 15 ft wide by about 3 ft high and 18" thick, and it's concrete with a lot of stone in it, probably 2" stuff.
My question: what do I do to get this right, and earn a permit without a year's worth of inland wetlands intervention? I realize I'm looking at some serious money, but I have some equipment to mitigate that. I still have to hire somebody for forming, and someone else to do the pour, but what do I need to make it right?
I'm hoping for real-world experience, but speculation from other smart people is certainly welcome.
thanks in advance, Keith