Pond Boss Forums POND CONSTRUCTION Building a dam Culverts in over flow spillway??

I know that its not recommended by some, but i wanted opinion from others. My lake is going to be right at 7 acres. My primary spillway pipe is 23" steel pipe with a 10" valve at the bottom of the riser in case i ever need to lower the height of my pond for any reason. Since we will be using our dam as our drive way to our house i am planning on putting culverts in at the overflow spillway and then pouring concrete around them. What do yall think? I was thinking 6- 24" culverts evenly apart.

There is 153 acres of water run off. Does anyone do this?

I don't see why it won't work.

We are planning something similar, although my ponds won't be anywhere near Texas size. A dirt mover friend was over here yesterday, and we are planning on putting a riser on the 30-inch culvert under our main driveway. The driveway has been there about 30 years, and we bring a lot of heavy loads over it. We figure it is pretty solid. There is a lower spot in the driveway, that is about 3-feet above the riser we are planning. We plan to dig out and fill about a 10-15 foot driveway section with rip-rap, that we will cover with with driveway gravel. It should provide an emergency spill way if the water should ever get more than about 2-feet above the top of the standpipe.

After talking to a friend in the road and bridge bussiness. I think im going to go with 5- 18" culverts and pour concrete around both ends of them as well as on top, but also keep this end of the dam a foot lower that way there is still a unrestricted place for water to flow if it ever did get that bad. That would put my dam roughly 3' above natural water level. Does this sound good?

I wouldn't let the water flow over the dam, I'd make sure it channeled thru the emergency overflow. I'd be afraid of it washing out the dam. If you're doing that because you don't think the emergency overflow is large enough, then I'd make it bigger. Think 5 years down the road, when all the fish are adults, and the pond is just what you wanted. You get a large rain event, the water goes over the dam, and washes it out. All the fish go downstream with all the water in the pond. What would it cost to fix and restock?

I wish I knew how to figure out how to properly size an emergency spillway, but that's not something that we need to do here in this flat land of North Central Indiana.

It wont be going over the dam. It will be going over the spillway, It will almost have a 2 stage spillway if that makes sense. The culverts and then on top of the culverts.

Now I get it! Thanks for the clarification.

David, were you around for the 11 inch rain back in Sept 09 ( our pond is on the other side of Pittsburgh off 11)? I had two 18 inch pipes and the water brought so much trash that my pipes were plugged up. After that, I went with four 24 inch pipes in my little pond and I have not had another problem. In fact, I have never seen it rise more than 3 inches over full pool (8 inch is syphon pipe is used to hold the level)

What I am saying is that I would use the 24 inch pipes even if you use fewer of them. They are much harder to plug up with trash ( branches, tree trunks, ect.) And in the end, the cost is about the same and it is a very small part of the overall cost. We do get some really big downpours in East Texas.

Just my 2 cents.

Yes I had just purchased this property and its the one time that I could see just how much water ran down the creek in question. Our present drive way is just north of the lake location and we have 1 18" culvert under it. There was no way for it to keep up we had water running over our driveway. It would have taken 3 18" culverts under our drive way to move that amount of water.

What type of pipe are you thinking of using, and how will it dump out on the backside of the dam? I ask because I may want to do this as well, for the same reason.

Double wall plastic pipe. It will dump out in a wide flat spillway just like any other dam.

David,

I dont mean to steal your thread, but I thought it would be silly to start the EXACT same topic for my questions.

I have the same issue as you! i need to make the dam my road, and I dont want to have to drive over water... even in that 100 year rare time.

My pond is going to be 3.5 acres in size. it is a small ravine that we have dammed. The area has about 400+ acres of watershed, but we only get 23 inches / year here. The old-timers here tell me that "major water can run through there". they think I am crazy for building my house on the other side.

They also swear there is live water int he bottom of this ravine, but i bought the place in the worst drought since 1950's, and I think they are correct, water is now running in about 15 GPM.

My dirt man spoke with NRCS and with pond dam piping ltd, and they came up with plan to use 12 inch siphon and a separate large concrete spillway, that might get used occasionally.

I love the idea of a 2 stage spillway, so our vehicles can cross without fear.


I have pictures of my rough spill way, it still has some work, but im thinking of placing pipes like you... any thoughts Fellas??




The Armada is there to show you the size. it is a good sized spillway. at least 7-8 foot below the top of the dam.





On the dam, which is very wide, btw, you can only see the top of the car!


Thanks

DRP