Attn: georam RE SMALL POND SEDIMENT REMOVAL

[ACSCorp]

I saw a post titled "SMALL POND SEDIMENT REMOVAL" which is closed but wanted to respond to this. I found a quite ingenious method we will be using once we repair our dam since silt removal was estimated in the $100,000 plus range for our location (5 acres in size impounding 21 foot acres).

This is not an add. I have no affiliation with this company. They seem to use a simple bass boat with a gas powered farm pump to suck out the silt.

http://waterfrontremodelers.com/index.html

There is a video on the site in addition to pictures. One could build something like this for under $2,000. My question is what is the box that hangs off the side of the boat. It is my guess it is some type of silt trap and the excess water is discharged back into the body of water as you will see in the video (shooting in the air off the back end of the boat). This is the only thing that has me stumped as to how this silt containment box would work.

Of course the suction device would need some type of cage to prevent larger debris from being sucked in to avoid damage to the pump but that should be relatively simple to construct.

I hope the original poster of this question (georam) see this. I believe this is the solution to his question.

 

[dgillette]

If the "silt" is actually silt (i.e., passing #200 sieve, 75 microns, and larger than 2 or 5 microns, depending on whose definition you use) or clay (smaller than 2 or 5 microns), you probably can't separate it from the water at the boat, so it would require pumping to a settling pond. If it's actually clean sand, you may be able to do something at the boat.

How will you dispose of the silt? Let's say it's an average of 3 feet thick over 5 acres. That gives 24,000 c.y. at its present density, with some bulking likely, especially if it's plastic. Got a friendly farmer who will let you spread it on his cornfield in the fall after harvest? It may contain a lot of nitrogen and phosphorus, especially if there is runoff from lawns or fields.

With some materials, you may get some significant shrinkage of the "silt" just by drying it. Give that some thought.

(If it has been kept submerged constantly for many years, it may smell pretty foul due to those reduced sulfur organic compounds. A couple years ago, a ditch company dredged a small equalizing reservoir near my office, and for a few days the smell would knock a buzzard off a [manure] wagon driving by.)

 

[ACSCorp]

Thanks. We have 16 acres in the subdivision and I myself own 2.5 acres I could spread it on. We also have allot of farmland around us we may be able to dispose the remainder.

If not, we will have to pay to have it carted off. I understand if it is dry, it is treated differently than if it is still wet as far as hazardous material handling not to speak of the increased volume and weight. We have done chemical analysis on it and it is within the standards for heavy metals with oddly enough, very little fertilizer nutrients even though the entire area that drains into the pond is farmland. There is another smaller dam upstream that probably is acting as a silt trap and is holding most of them.