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

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.