Dam for Auxiliary Pond at Existing Pond Entrance - 11/05/11 02:57 AM
Last year I asked about the feasibility of adding a small 30' diameter auxiliary pond at the entrance of a wet-weather ditch to my existing 1 acre pond.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=218864#Post218864
The main purpose would be to provide an area for the frogs and other critters that disappeared when I added bass to the existing pond. I sure would appreciate some advice before I start digging.
Even though the two ponds would be essentially the same level at full pool, I am thinking about using a dam between the two, so that I could pump water from the existing pond during dry weather to keep the auxiliary pond full. I gave some thought to a concrete dam, but I'm thinking now that I ought to stick with a small earth dam. Right now looks like a good time to do it, since the existing pond is down about three feet due to the extreme drought we had for the last two years. Here is a schematic diagram of what I am thinking about.
At full pool the two ponds would be at the same level. The red pipe would be for keeping the auxiliary pond full. The submersible pump would be in the existing pond about 4 feet below full pool and connected with a 2” PVC pipe. The green pipe is the main overflow pipe. The emergency spillway would be the existing low areas off to the West side of the new dam. Some remaining questions are what pump to use, how to construct the clay core, how to make the anti-seep collar, and whether I would need some sort of flap valve to keep water from leaking backwards through the pump.
Here is an image looking from the East to the existing junction between the two ponds along with overlays of what I am considering. My main concern is the dam itself. It would be only about 10 feet long, about 4 feet tall, and about 10 feet wide. I thought I would dig a trench and fill it with clay that I saved from the original pond. I would make the rest of the dam from dirt I excavate from the new pond area. Would a trench about four feet wide by 4 feet deep be close to right for the clay core? And would a mechanical vibrating packer be sufficient for a small dam like this? I'm not sure how I would pack it any other way.
Here is a view looking from the existing pond up the ditch.
And here is a view from the ditch looking towards the existing pond.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=218864#Post218864
The main purpose would be to provide an area for the frogs and other critters that disappeared when I added bass to the existing pond. I sure would appreciate some advice before I start digging.
Even though the two ponds would be essentially the same level at full pool, I am thinking about using a dam between the two, so that I could pump water from the existing pond during dry weather to keep the auxiliary pond full. I gave some thought to a concrete dam, but I'm thinking now that I ought to stick with a small earth dam. Right now looks like a good time to do it, since the existing pond is down about three feet due to the extreme drought we had for the last two years. Here is a schematic diagram of what I am thinking about.
At full pool the two ponds would be at the same level. The red pipe would be for keeping the auxiliary pond full. The submersible pump would be in the existing pond about 4 feet below full pool and connected with a 2” PVC pipe. The green pipe is the main overflow pipe. The emergency spillway would be the existing low areas off to the West side of the new dam. Some remaining questions are what pump to use, how to construct the clay core, how to make the anti-seep collar, and whether I would need some sort of flap valve to keep water from leaking backwards through the pump.
Here is an image looking from the East to the existing junction between the two ponds along with overlays of what I am considering. My main concern is the dam itself. It would be only about 10 feet long, about 4 feet tall, and about 10 feet wide. I thought I would dig a trench and fill it with clay that I saved from the original pond. I would make the rest of the dam from dirt I excavate from the new pond area. Would a trench about four feet wide by 4 feet deep be close to right for the clay core? And would a mechanical vibrating packer be sufficient for a small dam like this? I'm not sure how I would pack it any other way.
Here is a view looking from the existing pond up the ditch.
And here is a view from the ditch looking towards the existing pond.