Pond Boss Forums POND CONSTRUCTION Building a dam Replace galvanized outflow pipes with plastic?

Hello everyone.

Has anyone used corrugated plastic outflow pipes for their outflow? I currently have two 24" galvanized metal culvert pipes that provide the outflow and I wanted to replace them with four 24" corrugated plastic pipes. I'm looking to increase the longevity of the system and flow.

Does anyone know how long plastic pipe will last? Has anyone used corrugated plastic pipes for outflow? I only see galvanized pipes on ponds here (I am in PA).

Thanks,

Sam

Sam...the pond I bought has corrugated black plastic. Recently I had Mike Otto the pond building guru out for a consultation and he said it was good thing to have the corrigated plastic because the metal outflow pipes don't last near as long. Mike said the metal corrugated pipes trap water and start to rust/rot. Below is a pic of mine.

Hi Zep. Thanks for the picture. Can you explain what I am looking at for the entrance there? It looks like you took a piece of the pipe, cut the top off, and then joined it to the outflow pipe with a gasket of some sort? If so, can you use that to fine tune the level?

My pipes lasted about 12 years. I could probably get another few years out of them. My pond rises and falls about 6-12" in spring/summer. I wanted to put 4 in to give more outflow area to stop the rise. I was also thinking about using concrete box culvert.

There's single wall and double wall corrugated plastic pipe. The pipe in the picture is a double wall pipe. It is stronger than single wall and I believe it will flow more water volume per given size due to the smooth interior.

I believe the larger sizes come in 20' sections, and they have to be joined together with a sleeve that goes on the outside of the joint and is tied together with zip ties.

When I installed mine, I bought a 90° elbow and used it with a short section as a stand pipe. I was concerned about water leaking out thru the joint, so when I assembeled it, I caulked the inside of the sleeve heavily with roofing tar, then assembeled the joint.

Hey Sam,
Since you are located in PA, you will be dealing with freezing temps. If you elect to go with plastic (as I did for our project, also in a freeze prone region), use double wall for the first section feeding into the spillway and double wall for the last section at the outlet below the dam. The smooth bore of the double wall will shed water with the potential of freezing, thereby minimizing the possibility of an ice dam at the areas most exposed to the freezing temps.
The cut out section of the pipe in Zep's spillway will increase the volume of water able to enter the pipe during extreme outflows and minimize potential for vortex.

Does anyone know how to search for culvert suppliers? I am west of Indianapolis and cannot seem to find where I can purchase them. Any ideas on what serach terms to put into Google?

Plumbing Supply Company is where I got mine. Check for the commercial guys who sell septic systems, etc.

RAH, Carter Lumber up here is where I bought mine. They stock single wall, but can order double wall.

Thanks guys - All of our Crater Lumbers have closed up around here.

Actually I believe Brettski is in error (sorry) in stating that the cut out section of the pipe in the picture above would minimize vortex formation. The engineers who have designed my dams use a hooded inlet on pipes, so that when the water level is above the top of the tube, a vortex cannot form. A vortex forming will swirl air down into the tube and reduce its capacity. The hood prevents this vortex, so the water flows in a more laminar motion into the tube inlet.

If the tube in the picture was rotated 180 degrees, this would be a hooded inlet, and that what the NRCS engineers I've worked with would do in this situation.

The other thing to be careful with when using dual walled pipes (which I would definitely use over singe walled), is that they are bouyant. The first few feet of the pipe are only covered by a few inches of soil, gradually working up to a couple of feet. In a heavy rain, the water can soften this soil, allowing the end of the tube to lift up. Althought the tubing is pretty rigid, I've had it bend in these situations up to 30-40 degrees. Thus I would recommend placing large, heavy rocks on both sides and around the top of the tube. This will weight it down, and also keep varmints like muskrats from burrowing along the outside of the tube. We learned this the hard way.

Bill

agreed; thx for the tuneup
from Pub 590:

They now make a stronger version of the ADS black plastic pipe it's more rigid and will handle more head pressue than the standard stuff according to the manufacture. I recently replaced my black pipe which had a blow out under the dam http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Main=22034&Number=279372#Post279372 with the new rigid type which is grey in color. You can also install aluminum piping as another option. The plastic stuff is not intended for high head applications but I beleive a paddle wheel scrapper or D6 dozer from recent pond work did mine in not head pressure. Here is a link to the ADS site http://www.ads-pipe.com/en/ you can probably find a sales rep in your area to purchase it.