building a duck impoundment- could use some input

As I've mentioned in a few previous post, I am in the planning stages of building a small (1.5- 3 acre max) impoundment. The land site is a heavily wooded, fairly flat river bottom with a nearby backwater lake that could be connected too via ditch or pipeing. The lowest, most suitable portion for the impoundment is at water level. When I dug a few holes it is moist top soil for a few inches, then watery river sand for a 12"- 20", then it appears to hit clay. As I shoveled the holes they filled back up with water just as fast as I took it out. Kind of like digging hole at the beach. There is a natural rise of about 2 1/2' of berm around the edges of where I'm looking to build it.

My original thoughts were to enhance the berms, install watercontrols and flood it but I don't think I can afford to keep it pumped full of water. I believe it will weep through the sand back into the water table. My next thoughts are to dig it out down to the clay but it will be filling up as fast as we dig it obviously, and water level will be uncontrolable for the most part. My main equipment is a IH/Dresser 175c track loader and to be honest I'm a little nervous about getting it in the water and getting it marred up. It's running on the skinnier tracks after all. Any of your thoughts or experiences will be appreciated. I'll try to take and post some pictures tomorrow if that will help.

 

This piece of property is very close to a power dam on the river. Upon investigating a little further today, indeed I DO NOT have clay under the river sand.

Heres a pcouple pics of the general bottom area I'd like to build a duck pond in





a couple pics of a long skinny pond created by a low area at the base of the hill that filled up from the risen water table due to damming the river.

 

Heres the hole I dug yesterday in the lowest portion and you can see the water table is just right under the topsoil


3 1/2foot ground rod


sunk to the handle and just keeps going = NO CLAY HERE


Another hole I started digging 100 yards away





Any thoughts or ideas ???

 

I know nothing about rice other than how to cook it, but the other thread got me to thinking. How would rice do in these shallow ponds and would it do much for the ducks? SO far, clearing around the edges and planting jap. millet is the plan.

 

I'm out of the flyway. What I've got is decent resident wood duck numbers and a few mallards. The available ducks are using this and the neighboring ponds.

 

I've already got beavers. they will not be any help here. that water in the picture is not moving. It's a pond that formed just from the raised watertable due to daming the river. there are no creeks in there to damn up either. I think I've got it figured out though, but we'll see.