Pond Boss Forums POND CONSTRUCTION Building a dam spillway in winter

1/2 acre
6' deep
Right now I have a 6" pvc horizontal overflow pipe under my driveway that handles the pond overflow. The pipe heaves every winter It's not 3' below grade. I thought about installing a standpipe system. The main would be below the frostline, and elbow, then the standpipe cut to the desired pond water elevation. Problem is, I think. I'll be having all kinds of ice problems. What will happen when the pond freezes? That standpipe will never make it through the winter.
What should I do?

Welcome to PB. I’ll let those who have seen frozen water reply.

I get ice, but have no direct standpipe experience.

Back in the dawn of time, my cousin's pond (here in Ohio) had a standpipe drain with a horizontal pipe at roughly the level of the bottom. It was a steel pipe, and had no problems until rust caught up with it.

The way I understand it, if the Winter water level is below the standpipe entrance, the pipe would have to withstand ice pressure. If the water level is above the standpipe, the flowing water will not freeze.

Now on to actual experience from someone ...

Do you have valuable fish in your pond?

If so, winter aeration might be a good idea to avoid a winter fish kill. (It sounds like the pond is near your house, so you should have AC electricity relatively close for aeration.)

If you built a traditional standpipe outlet with the winter aeration adjacent to the riser, that might get you safely through NJ winters and help your fish. You could move the aeration to a different location to help the fish avoid summer stress (or aerate for muck reduction, etc.).

Another option for an existing pond is to build an automatic siphon system. It would have air in the PVC for most of the winter, but would run if you got a big winter rain. A siphon installation would probably involve less excavation on your end compared to a standpipe and deep horizontal pipe through the dam.

Here is a link to a schematic drawing of a typical system.

Link to Siphon Drawing

I believe some Pond Boss people have run this type of system in heavy ice conditions. I recall someone reported that the ice did break off the "air break" system at the top of the siphon one winter, but it was easily repaired if you used threaded connections for the at risk parts. (Plus the siphon pipe would fail in the "safe" position, since it would still run water if your pond level rose above the break.)

Hope that gives you some more ideas.

Maybe some of our northern pond people will drop into your thread.

Fish are of no real value, Not near the house so electricity is out. I'm looking for a low cost, no maintenance solution. It's just a pond in the woods.
In the worst case scenario I'll just keep the horizontal overflow and tolerate the heaving.

You don't have to have electricity at the pond to have an aeration system. You can bury black poly tubing to the pond, and split it there for summer and winter aeration. I'd go the aeration route to keep the standpipe where it's supposed to be and not affected by the ice.