Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? Old Pond Silt and Dam Failure

Ok, let me give you the history of his old family pond as it was told to me this evening.

Around 1960, a pond was created when beavers dammed up the south end of a small spring fed creek. They basically built their dam perfectly so that a trickle remained, flowing under a bridge. This pond is said to have been nearly 30 feet deep.

Years go by and the pond is silted in. Beavers abandon the pond and the dam fails. Now there is a tube that runs under the road for the creek to exit what is now a marshland of sorts.

First view here is an aerial. Please help me determine how large this pond is. If I had to guess I'd say around 2 acres, though I'm not exactly sure, on this aerial, how far north the water can potentially go. This photo was obviously taken before the dam failure.



And this is a bird's eye view of the property. The pond in question is the one just north of Hackberry there. It doesn't look to stretch that far north in this picture, but who knows at what stage of drainage it was.



Here is the drain pipe that runs under the road. Directly in front of it (left in this picture) the beavers had created their dam that basically made a U-shape around the pipe, effectively damming up the water.



The water level is said to have been the top of that small hill in front of the drain pipe. It is now approximately 5 feet from the leveled off silted in pond bottom.

Picture at pond bottom level.



Very saturated.



Creek runs through this low area that was once the pond. It branches off here and there, but ultimately just leads to that drainage pipe.

Photos taken facing south.





Photos taken from the road at various angles.









Photo taken from west shore.



So, where do we go from here? I believe we need to take a few feet of silt out. How do we go about doing this? And is it feasible to replicate how the beavers made their dam, by simply building it around this drainage pipe, letting it trickle over?

Omahah, go to a topographical map of the area, look at the elevations. Find the elevation that the pond is at now, add 5' to that and look back up and out to the sides of the drainage for that level. Then try and trace around that rough area using google planimeter to give you an area.

Digging the silt out will be a job for an excavator. Do you have a place to dispose of it? What you're planning is feasible, providing you have good dirt for the dam and a way to compact it. I'd do some searching to see what the state/county says, and try and figure out what would happen if the dam were to give way. Would the road wash out?

It seems that, sooner or later, beaver dams on streams always silt up and blow out.

Siltation always has to be considered when you try to stop up running water.

What's a good site to get some quality topo maps?

I have plenty of places to displace the dirt if needed and I have some really good clay to use on the dam. I don't know if the road would wash out, I wouldn't think so because it never did in the 50 or so years it's been full.

Dave, should we maybe dig it deeper with this in mind, knowing it'll silt in quicker than other ponds?

How's this...

I've used www.MyTopo.com to get topo maps printed of areas that I hunt. You can customize what you want printed.

I think so Omaha. Anytime you dam running water you can expect to have a lot of junk carried downstream. And, a dam stops it.

Ok. So how deep do you suggest? It used to be 30 feet, from what I'm being told, which would be awesome, but also a TON of work and I'm not sure the guy I'd be asking would be up for it. Doesn't hurt to ask I suppose. Should we just go as deep as he's comfortable with?

Omaha, I doubt that it was 30' deep from just beavers damming it up.

If it was, lets figure that it lasted 40+ years. So, that's filling in at a rate of 6" to 9" per year. How long you want the pond to last should dictate how deep it's dug. The deepest holes will fill in the quickest, so in the beginning the pond will get shallower at a quicker rate.

You're probably right Scott. I'm getting all this "history" from a grandma who may or may not know anything about it and a uncle who exaggerates.