Pond Boss Forums POND CONSTRUCTION Soil questions Water table pond

Sort of cliff notes here (from first hand, personal experience). If you search for groundwater pond you might find pictures of mine.....

1) Slope pond banks no steeper than 3:1 - 4 or even 6:1 would be better because if the water table drops you will be mowing the dirt that would be normally under water.

The caveat of that is if the water stays high for a long period, those areas will be great for growing underwater or emergent plants, which might make fishing difficult. They can be controlled tho - chemicals or grass carp. I'd also say Tilapia, but you are in Illinois and they don't allow them.

2) When digging the pond, make sure you have a 3" semi-trash pump available, with intake and discharge hose long enough to get the water away from the pond where you are digging. Digging in water = more time and $$ spent, plus more wear and tear on the equipment.

3) Think about putting a floating pier on the pond. That will make utilizing the pond easier due to the fluctuating water levels.

4) Cover for the fish: Think about floating islands. Any cover you place in less than 4', maybe 6' of water might be out of the water at least some time of the year and aesthetics might not be as desired.

5) If you run into clay, stockpile it and use it to line the pond when done. (Doing all the proper compaction methods when it's placed back in the pond, blah, blah, blah.) If you find enough, you might not have to deal with a groundwater pond!!

6) Have enough erosion mats, Rye or Bermuda grass seed and a plan for watering the grass seed in place before the pond is completely dug. Getting the dirt out of the hole and watching a large rain event coming is no time to be scrambling to find erosion mats and grass seed.......

In Illinois, I'd like to see winter water pond depth of 10'-12' over at least 40+% of the pond basin. So, if the water might drop 5' in the summer/fall, that means digging down to 17' deep. FWIW, I dug mine to 22' deep and had 3' of sediment wash back in during a VERY hard rain before I could get erosion mats in place.