concrete bunker blocks pond dam

[marhar]

I wonder if I could make a small farm pond with bunker blocks. The land naturally slopes toward a wet weather stream. I would place one row of blocks for a dam roughly 15' long. The water would be the depth of the block and extend about 15' from the dam. If the dam failed it would only flood the current stream bed; the risk is small.

Any thoughts?

 

[Streetcar]

How do you plan to seal around the blocks to stop leaks. Failure of dam could result in large amount of water in short time leading to damage

 

[mikester]

If you have ANY environmental laws in your jurisdiction you may find it impossible to get permission to dam a waterway and costly to remove because it's even harder to get forgiveness.

 

[ArlyA]

Seems those bunker blocks are not made for pressure on just one side. I'd suggest you get plans and do it right....

 

[Rustyiron]

All of those that I've seen are only 2' high. They are pretty crude and l don't see how you'd ever really seal them to the ground and each other.
Oh, there also 150# per cubic foot and 2x2x6 is a common size. Can you unload and set 3600#?
Sorry to be such a downer, a small water feature is nice but I think you'll pull your hair out trying to get it to hold water.

 

[Jrasband]

you would need to have a earthen dam in front of the blocks that is well tamped. I suppose you could use 1/2 the amount of dirt by using the blocks, depending on how much water were talking about of course. I wouldn't go more than three blocks high above grade.

 

[LouNY]

Put the mafia blocks in a slight curve so the push of the water will tighten them together, heavy mill plastic and an earthen berm in front. Your spillway will be the hardest to setup to be non erroding.

 

[Jrasband]

Bury the overflow pipe under the dam! very important. No need to have a spillway unless the pipe can't keep up. If you ever need drain the pond( to dredge it, or fix leak) you will be glad you put that pipe in there.

 

[rScotty]

Sure you can - if local regs let you get away with it. How many do you think it will take to do the job? I expect you'll place them side by side so they are end-on to the water. And that makes it easy to chain them together. The other way with the flat side to the water doesn't make much sense.

I've been thinking about doing the same thing as a flood barrier . They are only two feet wide at the base, so it takes quite a few.

The ones I see have lift points cast into the top which makes them easy to place. If you are thinking of placing them with a backhoe and chain through the lift points....Well, I tried that with a 3500 lb concrete well top last fall. A full size backhoe back hoe was barely up to the task. It did it, but I carefully kept the weight in close to the tractor. Even so, the front end got light. Made me wish for an excavator.
Or maybe just use the loader instead.

rScotty

 

[EddieWalker]

Just about anything can be used to build a dam. I think the size and weight of the concrete blocks would make a great dam. Water would just flow over it when it's full. The better you seal it, the better it will work. How are you going to get them into position?

Once in position, you'll need to have something on the back side of the blocks to stop erosion from the water flowing over the blocks. That water will remove all the soil under the back sides of the bocks if you don't put something there. Concrete sacks might work.

Here in Texas, you can dam any creek that doesn't have a name. Just look at a map and see if it's named. If it's named, you need a permit from the Dam Authority that controls that creek.

 

[Rustyiron]

Dam Authority that controls that creek.

That's my opinion too Eddie

 

[marhar]

you would need to have a earthen dam in front of the blocks that is well tamped. I suppose you could use 1/2 the amount of dirt by using the blocks, depending on how much water were talking about of course. I wouldn't go more than three blocks high above grade.

I am just tinkering with the idea but I would only go one row high.

 

[marhar]

How do you plan to seal around the blocks to stop leaks. Failure of dam could result in large amount of water in short time leading to damage

I am wondering about V blocks that interlock (they will still leak some).

 

[marhar]

Sure you can - if local regs let you get away with it. How many do you think it will take to do the job? I expect you'll place them side by side so they are end-on to the water. And that makes it easy to chain them together. The other way with the flat side to the water doesn't make much sense.

I've been thinking about doing the same thing as a flood barrier . They are only two feet wide at the base, so it takes quite a few.

The ones I see have lift points cast into the top which makes them easy to place. If you are thinking of placing them with a backhoe and chain through the lift points....Well, I tried that with a 3500 lb concrete well top last fall. A full size backhoe back hoe was barely up to the task. It did it, but I carefully kept the weight in close to the tractor. Even so, the front end got light. Made me wish for an excavator.
Or maybe just use the loader instead.

rScotty

We are kinda think of the same type of project. The land drains down into a valley. The valley will have a small pool of water that is at most 4' deep. Sometimes it will spill over during a hard rain and make the pasture soggy. I would like to hold back enough water to keep the pasture drier and still have enough water to use for the cattle.

 

[rScotty]

We are kinda think of the same type of project. The land drains down into a valley. The valley will have a small pool of water that is at most 4' deep. Sometimes it will spill over during a hard rain and make the pasture soggy. I would like to hold back enough water to keep the pasture drier and still have enough water to use for the cattle.

The ones I was looking at here are called road barriers. They come in 4, 5, 6, and 8 foot lengths and weigh from 2000 to 4000 lbs. these had rebar loops cast into the top. New cost is expensive, but I sometimes see them for sale for $200 apiece for 8 footers in the places that sell used building materials - so somebody must be finding a use for them. Seven or eight would do your dam, and then backfill the slots between with gravely dirt ought to do it. Might even grow some grass between the tops.
rScotty

 

[Streetcar]

I am wondering about V blocks that interlock (they will still leak some).

The v blocks are not water tight at joints or beneath blocks. The constant leaking will cause problems.

 

[Smokeydog]

That’s why they make pond liners.

 

[EddieWalker]

Pond liner, Heavy Duty Plastic, Mortar, or even Expanding Foam. For something like this, I would go cheap and simple. Eventually silt will build up and form a seal of its own.

 

[dirttoys]

Just about anything can be used to build a dam. I think the size and weight of the concrete blocks would make a great dam. Water would just flow over it when it's full. The better you seal it, the better it will work. How are you going to get them into position?

Once in position, you'll need to have something on the back side of the blocks to stop erosion from the water flowing over the blocks. That water will remove all the soil under the back sides of the bocks if you don't put something there. Concrete sacks might work.

Here in Texas, you can dam any creek that doesn't have a name. Just look at a map and see if it's named. If it's named, you need a permit from the Dam Authority that controls that creek.

this is well said, I would be careful about letting water flow over the blocks as a spillway, it will undercut the back of the block and cause problems.

 

[Streetcar]

Pond liner, Heavy Duty Plastic, Mortar, or even Expanding Foam. For something like this, I would go cheap and simple. Eventually silt will build up and form a seal of its own.

Eddie
most of the times a leak will get worse on a dam. the leak will concentrate flow in one area and scour a large hole. A cheap solution is many times the most expensive in the long run.

ps why is your Facebook tag in Cyrillic