Pond Boss Forums POND CONSTRUCTION Building a dam I hike a different route

I'm Beaverboy, and I'm a curious animal with a home range of about 3 miles. I like hiking about and enjoying the landscape and seeing my fellow animal friends. A place that is about a mile away from my den changed considerably in the last year. I would just cross a stream and continue on my journey. But I saw the steady stream of water and even I thought how tempting it would be to dam it up. Well, my thoughts were answered, and the owner built a pond there.

Since I find it interesting when others post before and after pics, I thought I would show some pics of a place I frequently visit. The watershed drains something like 260-280 acres. Not sure how big the pond is. I'll just guess over 2, less than 5 acres.
Pic of the stream during peak snowmelt during early 2007


more pics to follow

Thanks for the picture.

That looks like a lot of water for 280 acres.

Yep, with it being hilly and most of the watershed in cropland, it can be a good amount of water running through it. The pond started to get built in September 2007 and was finished by October. By December '07, it had already filled up and was at normal pool level. Think it has a 2ft diameter pipe. By June 2008, heavy rains caused that pipe to run at full capacity.

Here are some pics of before and after

before/after(floodstage) of the backwaters



Another pic at normal pool level

Looking upon the pond during the flood


ducks that are attracted by the pond

BB, you probably don't know who Johnny Appleseed was, but you remind me of him - and that's meant as a compliment. Great work!

Oh indeed, we were taught about johnny appleseed in school.

Also, a week ago I saw an online nursery selling an apple tree that was linked to johnny appleseed, so I was reading info about him.

Nice, gives me some inspiration for a smaller stream flowing through my timber. I'll get the Kubota down there this summer when it slows down and make a pool. Or two.

Just a few other pics to complete this thread
Aerial before and after



Casting a spell


another pond I came across on my journey, a beaver pond, eh!

Quite the transformation. Aerial shots really tell the story. That beaver pond doesn't appear to have been cored. Boy, are they gonna be sorry.

Brettski

Your comment about the lack of a core in the dam piqued my interest in a more general way.

I am looking to purchase a property with an existing pond. In my site visits of existing ponds I have tried to apply what I have learned from this site to help avoid a future ooops. As a result this site has helped me in several cases to avoid a problem. So thanks to all and keep the great info coming.

Back to my question. How can you look at an older existing pond to determine if the dam was built with a core and/or otherwise constructed properly?

Any thoughts

NAP

I have seen some pond construction faux pas that were quite obvious: Dams noticeably lower in the middle than anything approaching an emergency spillway at either end, drainpipes so close to the dam's top that freeboard is basically non-existent, and water levels that are significantly lower than other nearby ponds currently are (I actually only have to think about one specific pond near me to visualize all three of these). The latter is IMHO a sign that the dam was not cored or even constructed of good, compacted clay.

I also know of one pond which I would describe as having been cored after-the-fact; water loss on this BOW dropped a lot from having a core added (to the back side of the dam, IIRC), and in dry weather is now about 3 feet fuller than it used to be.

NAP, if it appears to be leaking, it probably wasn't cored.

Also look at the slope. Most should be about 3:1.

Get a TOPO map and look at the runoff area in relation to the size of the pond. Assure that a neighbor can't make changes to their place to restrict or decrease your water supply.

To determine whether there is a leak mark the pond water level. Then put water in a straight walled bucket and see if the water in the bucket drops due to evaporation less than that of the pond. If the pond drops more you probably have a leak.

Ascertain the age of the pond. If it is pretty old(?), you can bet it is silted. Most ponds have a life span.

Check on how it has been taken care of.
Is there grass on the dam? Trees? Has the spillway be washed out.

Theo, Dave and OTTO

Thanks for the advice. There are 2 ponds that I have considered that had many of the issues referenced in your responses with the exception of the sagging dam.

Another concern with these 2 and some other ponds that I have looked at is the lack of a drain pipe. Both ponds, a 1+
acre and a 4+ acre have less than 6" from full pool to the top of the dam and have a 10" - 12" PVC pipe along the back side of the dam as a spillway. In both situations there was evidence of past clogs where leaves and twigs had been removed from the entrance of the pipe. IIRC, the 4 acre pond actually had 3 of these pipes that drained into a creek that flowed along the back of the dam.

The owner of the 4 acre pond told me that it was built during he 30's by the WPA. Does anyone know if the WPA's methods required a core to be installed as part of the dam construction?

Another question has to do with the lack of a drain pipe. How difficult is it to add a drain pipe to an existing pond?

Thanks again guys

NAP

If you added a siphon system, it is super easy. If you want to add a standpipe, The entire pond will need to be drained and the dam breached.


Too bad someone has never made a "screw" type pipe like those used to bore under roads and such. The "threads welded onto those pipes would make a great anti-seep collar and you could add a stand with scuba gear or drain and finish.

If a dam was built 30 years ago and it holding water do not worry about it. The same is true for the spillway pipe, it is only there to protect the dirt spillway. Look at the dirt spillway see if it has erosion problems that will tell you if you need a bigger pipe.

As far as the leaves around the entrance to the pipe, there is always a little work that will need to be done to keep things clear.

Rainman and OTTO

Thanks. Makes sense.

With regard to the "spillway pipes" my concern with both of these ponds was that these pipes were the only way for the water to exit the pond. In both of these cases there was less than a
foot from full pool to the top of the dam. Also. neither pond has a spillway and from an amateur's view I could not see how a spillway could be added.

Any thoughts on how to resolve the above issues? Add more spillway pipes?

thanks

Dale