Estimate of cost to expand a pond?

[noose]

I've got a tank on my property that isn't big enough for me. I want to move it from "tank" to "lake". I've attached a picture of the current tank and a yellow line to indicate where I'd like to push dirt westward to catch the significant quantity of water than runs past it. This would likely take a sizable bulldozer to push the dirt west. There isn't much work to "deepen" it but going deeper would be plus. I think it would be cheaper to just push as much soil off the bottom to the west and build up the retaining wall height rather than trying too much to dig down. Just west of the retaining wall, the elevation drops off quickly to below the water level in the tank. The center through the property (just west of the tank retaining wall) is u-shaped and starts going back uphill after another 75 feet or so to the west. Extending the retaining wall far enough west will create enough opportunity to significantly enlarge the tank by not letting any water move south from the significant rise in elevation above it. If I was to hire a person with a decent sized dozer, what would you estimate the cost to be? The current tank is right at 90' from the top edge of the retaining wall to the top edge of the other side, east-west across the center. Pushing the soil west and building up the retaining wall height to match the existing tank would roughly double the width and be well over 10' in depth.

 

[kenmac]

I doubt anyone can even give you an estimate unless they live in your area, and know what someone with equipment needed for this job charges per hr

 

[oosik]

I have NO IDEA of the costs. Here is one thing to consider. Your existing "tank" is as big as it is because there is an impermeable layer of soil that holds the water in. Break thru that layer and you have NOTHING.

I suggest a local person with knowledge of the geology of your location. This will tell you what can & can not be done. Cost - ??? How high is UP??

 

[EddieWalker]

Figure a grand just to get the dozer delivered to your place, then $100 an hour to run it, and depending on your soil, and how much material you want moved to create a dam that you can hold water, and more material if you want the back side sloped enough to more or drive a tractor up and down it, probably $5,000 for that.

How good is your dirt for making a dam? Does it compact easily? A dozer is horrible at compacting soil, the tracks are designed to float on the ground and provide the minimum amount of pressure by spreading the weight of the machine out over all of the bottom of the tracks touching the ground.

How will you deal with overflow?

How much run off do you get there? From the look of the pond, it's already pretty low. Do you get enough run off during the rainy season to fill it up?

Is the water low because of poor soil that leaks?

Do you have rock or sand to deal with?

 

[Industrial Toys]

We had a TEREX 8230(?) get stuck in our swamp, building a pond and had to bring in a D9 to get it out. Get's expensive in a hurry.

More and more, you can't even do stuff like that without consulting some Government authority.

I had one contractor under estimate a large job by a HUGE margin. No excuse for that one. BUT, not a bad thing, because if I knew what it was going to really cost, I never would have done it, but am so glad I did, and now it's done, paid for a long time ago and forgotten.

 

[noose]

Figure a grand just to get the dozer delivered to your place, then $100 an hour to run it, and depending on your soil, and how much material you want moved to create a dam that you can hold water, and more material if you want the back side sloped enough to more or drive a tractor up and down it, probably $5,000 for that.

How good is your dirt for making a dam? Does it compact easily? A dozer is horrible at compacting soil, the tracks are designed to float on the ground and provide the minimum amount of pressure by spreading the weight of the machine out over all of the bottom of the tracks touching the ground.

How will you deal with overflow?

How much run off do you get there? From the look of the pond, it's already pretty low. Do you get enough run off during the rainy season to fill it up?

Is the water low because of poor soil that leaks?

Do you have rock or sand to deal with?

Thanks for all the data. The soil is a bit rocky and water can percolate through it somewhat easily when it is not compacted and there are no fines settled in. There is some clay and fine sediment that has settled in over time and plugged up the micro-holes so it doesn't leak like a sieve. There has been enough rain in the past to fill it up entirely and well up the hill but the low level right now is primarily limited rain. We had some recent and it has come up a couple of feet. The biggest challenge is probably 50% or more of the water moving downhill can go right past it. A significant amount does end up in the tank. Overflow would be something I'll need to look at. It might be worth building something either with heavy limestone rocks over a membrane or a concrete overflow area to keep from eroding the wall in a deluge. I've attached a pic from back when we had our annual amount a rain in the first 4 months of the year... My area gets about 40" annually, on average. There's about 18-20 acres "uphill" from that tank to fill it. The soil will absorb quite a bit so runoff isn't going to happen unless the ground is saturated. My hope is that by widening the tank to the "other side" of the low point, I can capture at least twice as much moving water and dig it to the point where it can back up to a point until overflow. Note in the attached image, that was a really wet time, lol. You can see everything is green as heck and where the water flows.