Questions about ponds on property

drkelly said:
The fiancee and I are looking at a piece of land for sale that has a pond on it. I don't know anything about ponds, so I am looking for some help/advice. It was definitely man made, and judging from the size of the trees on the dam it must be at least 30+ years old, maybe even 50+. It appears to have a pipe running through the dam, and also what looks to be an auxiliary storm drain run off area around the edge of the dam. The water is slightly murky. I have read that there are things you can add to the water to clear it up. I went for a swim off the dam to check the depth of the water, and it went over the 8' pole I was holding very quickly. From looking off the back side of the dam, I would guess the pond is probably 15 ft deep, or at least it was when it was originally built. I am guessing it might have silted in a little over the years. It appears to be fed by a very small creek/drainage. We have not had any significant rain out our way in almost 3 months, so the creek/drainage has limited water in it. I would estimate the size of the pond at about 2 acres. What kind of things should I check for or be aware of?
Thanks,
Danny
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I didnt read everyone's post so it's probably been said:

1. Anything with a berm height over 15' (lowest point to top) required (or should require) a permit to build and be designed/sealed by a PE.

2. Anything over 10-acre-feet in capacity is the same.

3. Is the aux. storm drain a pipe or is it something like a swale that would function as an emergency spillway? Depending on the drainage area (not just the creek) feeding into the pond you really don't want water overtopping your embankment.

4. What Diameter is the riser sticking out as well as the barrel downstream? Probably CMP?

5. Is the above leaking? IE do you have water comming out of the barrel without it overtopping the riser?

6. The back side of the dam should have the trees removed.

7. Any wet spots, seepage, etc. you see?


More than likely it's fine... it's been there for a long time obviously. The deal is if you decide to modify it or remove it you could possible run into some snags and have to spend some $$ to get stuff permitted/designed... If thats the case shoot me a PM and I could probably help you out.


As for the tree deal... I would remove the trees (1) trees do not provide any structural support to the dam structure (2) falling trees are not your main concern (3) Infiltration of water caused by the trees (especially roots) is the issue. Just cut them off at the bases too late to worry about the roots now.
 
uncc civilengineer said:
I didnt read everyone's post so it's probably been said:
1. Anything with a berm height over 15' (lowest point to top) required (or should require) a permit to build and be designed/sealed by a PE.
2. Anything over 10-acre-feet in capacity is the same.
3. Is the aux. storm drain a pipe or is it something like a swale that would function as an emergency spillway? Depending on the drainage area (not just the creek) feeding into the pond you really don't want water overtopping your embankment.
4. What Diameter is the riser sticking out as well as the barrel downstream? Probably CMP?
5. Is the above leaking? IE do you have water comming out of the barrel without it overtopping the riser?
6. The back side of the dam should have the trees removed.
7. Any wet spots, seepage, etc. you see?
More than likely it's fine... it's been there for a long time obviously. The deal is if you decide to modify it or remove it you could possible run into some snags and have to spend some $$ to get stuff permitted/designed... If thats the case shoot me a PM and I could probably help you out.
As for the tree deal... I would remove the trees (1) trees do not provide any structural support to the dam structure (2) falling trees are not your main concern (3) Infiltration of water caused by the trees (especially roots) is the issue. Just cut them off at the bases too late to worry about the roots now.
Click to expand...

1) It could be under 15ft, but is dam close if it is under. So would this be registered somewhere with the county if the pond was signed off by a PE?

3) The auxiliary storm drain is not a pipe, it is just a lower area around the end of the dam that appears like would act as a spillway. What is a swale?

4) I couldn't tell, but maybe 6-8"? Not really sure. What does CMP stand for? By barrel, I assume you are talking about the large pipe running horizontally through the dam? I would guess it to be 10" maybe.

5) I do not recall seeing any water coming out of the barrel (horizontal pipe running through the dam), but the area on the back side of the dam might have been wet. I really can't remember.

6) Maybe we should write that up in the contract to have the current owner pay to remove the trees.

7) Only wet spot I saw was at the very bottom on the back side of the dam where I guess the vertical pipe inside the pond drains to?

I don't know anything about ponds, so might need some education on some of the terms you are using. Do you know anyone I could call to have the pond inspected? Thanks for all the help.

Danny
 
drkelly said:
1) It could be under 15ft, but is dam close if it is under. So would this be registered somewhere with the county if the pond was signed off by a PE? I would think that it would become public record... not 100% sure... Do you think the current owner is the one who had it built? If ask them if they know.

3) The auxiliary storm drain is not a pipe, it is just a lower area around the end of the dam that appears like would act as a spillway. What is a swale? The lower area you're talking about is the emergency spillway or probably looks like a grassy swale (ditch). Probably a little lower then the crest (top) of the dam but just a bit (1' or so) higher up then the vertical (riser) pipe. Probably designed for the 10 year storm and when more water that that reaches the pond the riser pipe no longer has the capacity to handle it so the water flows down the emergency spillway as opposed to overtopping and potentially failing the dam.


4) I couldn't tell, but maybe 6-8"? Not really sure. What does CMP stand for? By barrel, I assume you are talking about the large pipe running horizontally through the dam? I would guess it to be 10" maybe. So you're thinking the vertical pipe is 6-8" Diameter and probably PVC right? Also the Horiz. pipe is approx. 10" again probably PVC? CMP = corrugated metal pipe... Probably doesnt matter I was just curious to see what was in place.


5) I do not recall seeing any water coming out of the barrel (horizontal pipe running through the dam), but the area on the back side of the dam might have been wet. I really can't remember.


6) Maybe we should write that up in the contract to have the current owner pay to remove the trees. are we talking 3" scrub pines or what here? In any event I would have the trees on the backside (downstream end) of the dam removed.


7) Only wet spot I saw was at the very bottom on the back side of the dam where I guess the vertical pipe inside the pond drains to? sounds normal if that's where the pipe is discharging to


I don't know anything about ponds, so might need some education on some of the terms you are using. Do you know anyone I could call to have the pond inspected? Thanks for all the help.
Danny
Click to expand...

Not sure on the pond inspection... I can tell you that if it was designed/sealed by a PE there should be a set of plans and design calcs floating around somewhere. The fact that it has a emergency spillway makes me think it was actually designed. Typically that's often omitted for farm ponds.

PM me the address if you have it and I'll do a little digging from here to see if I can find anything.

Chris

EDIT: What it boils down to is this... If the dam were to fail would it kill someone down stream? Would it harm a building, etc. ? Would it harm someone elses property? What I'm getting at is just enjoy it as a pond... cut down the trees and swim/fish in it. As long as it's not going to harm someone else in the event it ever (and probably never would ) failed, then you're just out a pond. See what I'm saying?
 
1) It could be under 15ft, but is dam close if it is under. So would this be registered somewhere with the county if the pond was signed off by a PE? I would think that it would become public record... not 100% sure... Do you think the current owner is the one who had it built? If ask them if they know. The current owner is a developer who bought the property from an old farmer. The developer is now in financial trouble and trying to unload the property. He was planning to build his own house on this property. Apparently the old farmer is not available. I already asked about checking with him on something else, and supposedly the builder lost contact with the old dude. Might be dead.

3) The auxiliary storm drain is not a pipe, it is just a lower area around the end of the dam that appears like would act as a spillway. What is a swale? The lower area you're talking about is the emergency spillway or probably looks like a grassy swale (ditch). Yep, looks like a grassy ditch.


4) I couldn't tell, but maybe 6-8"? Not really sure. What does CMP stand for? By barrel, I assume you are talking about the large pipe running horizontally through the dam? I would guess it to be 10" maybe. So you're thinking the vertical pipe is 6-8" Diameter and probably PVC right? Also the Horiz. pipe is approx. 10" again probably PVC? CMP = corrugated metal pipe... Probably doesnt matter I was just curious to see what was in place. Yeh, the the horizontal pipe is PVC, not sure about the vertical pipe.


uncc civilengineer said:
Not sure on the pond inspection... I can tell you that if it was designed/sealed by a PE there should be a set of plans and design calcs floating around somewhere. The fact that it has a emergency spillway makes me think it was actually designed. Typically that's often omitted for farm ponds.
PM me the address if you have it and I'll do a little digging from here to see if I can find anything.
Chris
EDIT: What it boils down to is this... If the dam were to fail would it kill someone down stream? Would it harm a building, etc. ? Would it harm someone elses property? What I'm getting at is just enjoy it as a pond... cut down the trees and swim/fish in it. As long as it's not going to harm someone else in the event it ever (and probably never would ) failed, then you're just out a pond. See what I'm saying?
Click to expand...

It would not do any harm if the dam failed. There are many acres of woods downstream of the pond, and no houses. I would guess the the largest trees on the dam are about 10" in diameter.
 
We have a pond out back that doesnt really show any negative effects toward us. Used for keeping the cows/horses cool and extra drinking water. I hardly ever see a water moc and after close to 80 years on the same property (grandfather build his house when he was 16) and thirty years with the man made lake we have never had a cow or horse bitten. Mosquitos arent really a big deal either but our house is about a two hundred yards from the lake.

A drained lake is MUCH worse with mosquitos. Dad wasnt too happy when we climbing the dam with the land cruiser destroyed the plug and drained the whole lake. :shaking:
 
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