I have got a hole about the size of a half dollar
4 feet under water level in the corragated stand
pipe. I am trying to stop it long enough to fill w/ concrette. Please let me know if you have any
ideas. The pipe is fairly rotten so have to be careful. it is 12.5 inches in dia.
Thanks in advance

Hey Bassin, I don't know that much about stand pipes, but concrete should set up under water. Is this something that could be repaired by sleeving a smaller dia. pipe inside the rotten one? Good luck with your repairs.

I talked to a guy last year who has a business putting clamp on type patches on metal boat dock piers. He works the Lake Granbury area southwest of Fort Worth on the Brazos River chain of lakes. He said they always rot or rust out at the water line. Maybe an internet search would turn up something.

How about sitting a 16" PVC pipe over it. Then filling the space between the two with concrete. The mud at the bottom should hold the concrete in.

Get in touch with our friends at Pond Dam Piping, in Macon, Ga. (800)333-2611. They are experts, and close to you.
Also, try Agri-Drain at (800)232-4742. They may have some productive ideas for you, too.

I believe Nick has the right idea. Go with a piece of PVC, steel or whatever is available and go with a pipe big enough to go over the OD of the existing pipe and then some, fill the 2-3 inches inbetween the walls with concrete. The people at Easyway Plastics, Inc also in Georgia (1-877-387-5472) also told me if you use PVC , to take a grinder and grind the pipe to a long gradual tapered point, this will aid in driving the pipe into the dirt as far as possible but it also roughs up the smooth material so the dirt,concrete,etc have a better chance of sticking to the pipe. This method is a temporary fix , once again but I have 2 ponds that have this and their still holding..... (knock on wood)