Pond Boss Forums GENERAL QUESTIONS Help Old pond drain valve construction

Hello, I am new to this site and am enjoying the vast amount of knowledge available here.
I have a problem that I can't seem to find any information on and am hoping someone is familiar with.
I live on a 27 acre lake and am attempting to get the drain valve in the spillway operational. The lake was built about 50 years ago and has a concrete block spillway about 20 feet away from the dam. Inside the spillway is a drain valve that is approximately 15" to 18" in diameter. It is operated by a 3/4" steel rod attached to the valve that extends to the top of the spillway. The end of the rod is threaded and has a nut with a flange on it that is attached to an angle iron structure to secure it. As the nut turns it lifts the gate allowing the water to flow through.
The problem is that the valve hasn't been operated for at least 15 years and the nut was rusted to the shaft. I was able to free the nut and slowly turned it, The valve opened freely and closed securely when I turned it back. I only opened it a small amount. I repeated this several times, opening the valve a little further each time. When I thought everything was operating correctly, I opened it quite a bit and noticed a change in the sound of the water. I attempted to close the valve but it would not completely shut off the flow of water, even with a lot of pressure on the rod. I hit the end of the rod with a large hammer and managed to almost close the valve.
I'm thinking something was in the pipe that reached the valve and didn't pass through it. Opening the valve completely may flush the pipe and allow the valve to operate normally, or, I may end up draining the entire lake. (This would probably create a lynch mob of the other 20 something lakeside property owners.)
I plan to consult the lake owner before proceeding with this plan.
Does anyone have an idea what type of valve I'm dealing with? It would be a tremendous help if I knew what I am dealing with.
Any help, advice, or condolences will be greatly appreciated.
d2a2

Yes, you should contact the owner before proceeding any further. He may be knowledgeable of the valve and have some experience with it.

Perhaps, a secondary valve or cap can be installed on the downstream end of the drain pipe before making any attempt to correct the situation. Good luck!

I have a similar situation in that our lake is 22 acres, 50 years old this year, and the drain valve is on a platform in the lake about 25' from the front of the dam. The spill pipe runs through the earthen dam and comes out the other side to drain into a creek.

We drain the lake about 4-6 feet every other year so residents can work on docks and walls. The problem is we do this during the winter and while its easy to open the valve, getting out through the mud and such to close it can be a real ordeal.

How easy would it be to install a new valve on the end of the drain pipe on the side of the dam where the water spills into the creek? What kind of valve would we want to use & would we simply open the other valve and permanently disable it?

Thanks for any input!

I'd be leery of putting a primary valve on the "out" side of the pipe going thru the dam. That would mean that the pipe in the dam would be pressurized at all times, and a tiny pinhole leak in the pipe could grow and compromise the dam, causing it to fail.

Is there another way it can be done?

A secondary valve would work for your intended purpose, however, depending on the size of the drain pipe it can be very expensive. A less expensive alternative may be to buy or rent an inflatable, or expanding pipe plug. (see link) After installing the plug, the water level rises, allowing access to the drain valve with a boat. After closing the valve, simply remove the plug. PLUGS

I am not quite understanding what you are saying here. Where is this inflatable pipe plug to be installed? The existing drain valve that we open is some 20' underwater.

Sorry about the lack of clarity. The plug would be placed inside the outflow end of the drain pipe, located on the backside of the dam. The same location of the proposed secondary valve.

What type of pipe is the drain constructed of: steel, pvc, corrugated, etc? What is the diameter of the drain pipe?

If the problem is getting thru the mud to close the existing valve, when you drop the level could you make a ridge of riprap (probably take a truckload or 2) to build up the area to allow you to get to the existing valve easier? This would be under water when the lake is at full pool.

The valve opening is 18' underwater and we would have to drain almost all the lake in order to get to it. I am going to speak with an engineer to discuss other options. I assume a mechanical engineer is who I need to be speaking with.

Here's a couple places to call. Since they specialize in drains for ponds, they might be able to help better than we can.

http://ponddampiping.com/index.html

http://www.agridrain.com/index.html

Considering the age of the valve, I'm hoping that the answer isn't "drain it down to get to the valve and replace it".

One more thing. Before you spend a lot of money repairing the valve or $$$ on installing another valve, contact a plumbing company that has a camera that they put in pipes to inspect them. Have them inspect the pipe to make sure it's not rusting through in places where it goes thru the dam. No sense in spending $$ on a repair that might only be good for a year before the whole pipe has to be replaced.

One last thought. If there isn't a good fix for it, check into having someone fill the pipe with hydraulic cement to seal it, and install a siphon drain. If set up correctly, you should be able to manually start the siphon and manually stop it once the lake gets to the level that you desire.

It just dawned on me: you are wanting to close the valve before the lake has completely drained; therefore, my idea of using an inflatable plug at the outlet would be difficult, due to the presence of water flowing thru the pipe. duh!


I wonder if snow shoes would allow one to walk on muck.

Now you understand what we are dealing with. We'll have wet mud until you get to the channel, then 10'-15' deep water until you get to the dock holding the rig that opens the valve.

To answer a question above, the valve is only 10 years old as it was replaced when it failed back in 2003.

If you wanted to discuss the how to's & what nots of what we are dealing with here, what kind of engineer would you speak with?

One that knows what he is talking about.

I'd start by looking for an engineer that was well versed in sewers and go from there.

Have you tried calling Pond Dam Piping?