This isn't my pond, but a friend asked me a question that I couldn't answer, but I'm sure someone here knows.

Here's the scenario:

The pond is relatively new (within a few years), and has minimal fish in it. It's approximately 1 ac. in size when full. The pond is dug in sandy soil, and is a ground water pond. No significant run-off fills the pond. The sides are currently sloped at roughly 2:1. There is not enough clay in the area to line the pond.

Currently there is 4' of water in the pond. The pond is about 6' below full pool due to low ground water levels. I have seen groundwater levels 12" to 18" lower than they are now, which wouldn't leave a lot of water in the pond for fish to survive the winter.

To dig the pond deeper, what are the pros and cons of draining the majority of the pond, damming up a small area with the current fish population and digging, vs. digging in the water without draining? When the ponds were built, the land immediately adjoining the pond was built up roughly 2', which keeps the pond from getting surface water. To pump water out of the pond, all that needs to be done is to push the water about 100' from the pond and it won't run back in.

Which would be more cost effective, a track hoe or a dragline? The dirt will have to be trucked approximately 400 Yards to be spread out, it can't be burned up closer to the pond. But, it can be burned up on site.

Or would there be a better option to dig the pond deeper?

The only other option that I can see would be to dig a well and continually pump water to keep the water level higher, but with increasing energy costs, and having to pump water during the coldest part of the winter, I cannot see that as being a cost effective option.

Dirt experts, how would you tackle the problem?

Diffinitely not a dirt experts (just see the post on my pond) but would Bentonite help sandy ground water ponds hold more water or would it hurt and keep water out? Maybe bentonite and pumping water would keep them full?

lassig, I looked into Bentonite when I was trying to figure out what to do with my pond. In this area, it's not cost effective because of the $ amount needed with the trsportation required, plus the volume of bentonite that would be needed without any gurantees that it'd fix the problem. I was seeing prices in excess of $40K - most of those were transportation costs. But, I know more now about using it than I did in 2007/2008 when I was researching it.

How big was the area that you did again and what type of soils did you have?

The pond is roughly 21000 sq ft of surface area. I ordered 10 Tons of 3/8 inch chip bentonite (actually have a ton still left). So I did a little under a pound per square foot. I have reasonable clay but there where some sand areas in the bottom of the pond that I hit with more bentonite than the rest. The 10 tons was delivered in 50 pound bags was roughly $3,400 dollars. I ordered it from a mine drilling supplier in IL and they delivered to site.

I could see if you have a couple acre pond and sandy soil requiring a couple of pounds of bentonite pre square foot it could get pricey.

Was wondering about the concept and if bentonite would help

Look around for a supply of powder bentonite. I found a place near me that almost gives the stuff away. Its just a real pain to work with.

i would have to vote for a trackhoe being faster simply because you can load a dump truck faster than with a dragline. a long reach trackhoe would do wonders here it sounds like ,if there are any in your area. i would dam up a small area or dig a small area deeper for the fish then get as much water out of the pond as possible. digging through water can get things muddy all around the pond pretty quick.

unless you till bentonite in it dont work to good unless the leak is big and will carry the bentonite into the dam. i did see it mixed in a 80 bbl vacuum truck once and it worked on a seep. it was mixed at a low concentration and looked like milky water when it came out but it did work the owner also had several small water pumps recirculating the water and bentonite in the pond all day long. he was a retired drilling rig hand that looked like he knew what he was doing. i remember him saying if you just pour it in there it wont disperse enough to find the leaks and i also remember he waited until the pond was full to do this.

to be fair on a dragline i have never been around one that worked properly so not sure what a good one would do

Thanks Tim. No dam, just a hole dug in the ground down into the water table. The area is very sandy, some spots were "sugar" sand. The ponds were dug in the old Grand Kankakee Marsh area that was drained by canals and ditches dug right around the turn of the century. There are long reach track hoes here to rent, IIRC, the biggest one is 5K/month (or was that 5K per week?) and it burns 10 gph. I think that one has an 80' reach. I'll be there tomorrow and take dimensions of the pond - laser rangefinders work great for stuff like that. I'll post some pics too.

In looking at the water level in my pond, the groundwater is the lowest (or very close to that level) that I've seen it in the 9 years that I've lived here. Even tho we had about 80" of snow this year, and it's starting to melt, it hasn't helped the ground water level a bit.

that sugar sand is real slimy when wet around here. i usually only find it in flood areas. if that trackhoe burns 10 gph it is a big one. even with the long reach boom it sounds big enough for a 1 cy bucket.

I'd lay odds a big track hoe would be 5K per week Scott.

I recently looked into renting a dozer. It was a Cat, 8ft blade, but dont know what model, pretty new. 950.00 per 8 hour day, plus pick up and delivery charges, plus fuel, plus a surcharge for over 8 hours per day. It really was not that big, about the size of a JD 450. Would easily cost over 5K per week. Pretty reasonable rates on all of the other equipment, but would probably cost me over 2K just to figure out how to operate it somewhat properly

So I am not an expert, but it sounds like (to me)

--He originally wanted a pond that was 10 foot deep, but now has one that is 4, so the idea would be to dig down another 6 feet to get into the groundwater further to get a 10 foot deep pond

If your friend did this he his paying to have another 6 feet x 1 acre of dirt dug, not to mention moved, and then he is still at the mercy of fluctuating groundwater levels.

If he has adequate rainfall, and a supplemental well, couldn't he spend his money on the install of a synthetic liner. Even if he downsized the lined project to 1/2 acre, at least he would have a beautiful 1/2 acre pond that held water like a drum, as oppossed to what he has now, and I bet the cost would be fairly similar

Experts?

Gallop, a liner is not an option. There's 4 ponds on the property totaling almost 4 acres. That's a lot of liners.

Yep, he'll still be at the mercy of the fluctuating water levels, but there will be more water for the fish to swim in during the winter.

Dunno if the RES made it in one of the ponds, the water got pretty cold due to the deep diffuser not being turned off 100%. Couldn't get to the valve to shut it off 'till things thawed out a bit (like this weekend).

I swung by the rental place and got their 2011 price guide.

Long Reach Excavators:
Doosan DX420 72' reach 72" bucket $4,100/wk $12.5K/Month
Doosan DX300 60' reach 72" bucket $3,300/wk $9.8K/Month
Doosan DX225E 50' reach 60" bucket $2,700/wk $7.9K/Month
They have Hitachi and JD long reach machines in those sizes as well, same price.

JKB, a JD450J Dozer w/6 way 8'9" blade is $300/day, $800/wk, $2,300/month

i believe the 225 or 300 gets my vote .225 probably weighs around 50,000 and will handle a 1 cy bucket and the 300 probably weighs in the 70's. the 420 is just to big for a small pond. a 450j with wide track would be nice for your conditions that sand may be rather pumpy

those prices are about same as they are in oklahoma. the long reach hoes are always more

Tim, you're pretty durn close! 225 is listed as 52,023# and the 300 is listed as 70K exact. The 225 comes with a 60" ditch bucket and the 300 comes with a 72" ditch bucket. I'm assuming those are buckets without teeth?

Here's what the latest pond looked like before the snow and cold hit. About a month after completion. It's a groundwater pond as well. No runoff going into the pond. The black dirt line is orig. soil (and surroungind soil in the woods) level.

thats a good picture i think the 225 would be sufficient it might reach across that pond in places. but if i didnt have a dozer for assistance would want the 72" bucket for grading purposes

Tim, I'll have some questions for you. I'll send you a pm this weekend. I need to go back and get more measurements, then put pencil to paper. This pictured pond is a bit bigger than it looks. When measured at the black dirt line (orig ground level) it's right at 1 3/4 ac.

tough decisions i get more uptight tryin to help some one than i do makin my own decisions

These questions will be easy for ya.