I am building a pond. Hope to start moving dirt in about 4 weeks. I've been told I need a drain. Looks like with pipe and valve that could cost $3000 or more. Is it worth it? Do I need the drain at the bottom? I'm impounding 19ft of water. Valve suppliers are telling me they have 12 ft stands or so - not 19.Should I be using steel or PVC? I will need about 180 ft of pipe if I put it at the bottom. Years from now will I want to just draw it down or why might I want to completly drain it?
Hey Jim K
a) some guys don't want any holes thru their dam, but want a drain so they go to siphon
b) some guys don't mind the pipe thru the dam and go in the direction that you have noted.
I'm one of the "b" guys
Lots of variables to consider, Jim K; those with more knowledge than me will no doubt chime in, but let me tell you about my experience with a thru the dam drain.
Pond: 3-4 acre, 17 feet deep, 700 ft wraparound berm, 90 feet thick at drain point. Twelve inch pvc sewer pipe overflow.Filled this winter, no leaks.
High pitched screech from lake end of drain pipe noticed in early February with noncoincident efflux of water in rapidly increasing stream from end of drainpipe. Changed pants. Plugged downstream end of pipe while stream was only at 9/10ths full flow. No joke-it took 3 men, a tractor, and a telephone pole and everyone got hypothermia, even the tractor. Capped sewer pipe, then built a form and put in 50 bags of concrete.
The contractor had not sealed the pipe properly, nor placed it in concrete, and as the dam settled, the joints in the dam gradually separated.
So whichever you choose, make sure your contractor really knows what he's doing. Myself, I'll never have another dam with anything hollow going thru it.
Oh and by the way, welcome to PB, I didn't catch your first post.
I have a 4" PVC drain in my 1 acre pond. Thought it would be wise in case of the need for mainanance. It has a PVC quarter-turn valve in a pit behind the dam so it won't freeze. I have had no problem in 5 years but I also have not used the drain. Seems like a siphon could always be used, so I am not sure if I would do it again. Not sure it the valve will work if I ever want to use it after not being used. Hope it does not break some day. Afraid to try it in case I break it.
I drained my upper pond without a drain pipe. I used a siphon. It worked great .. until it stopped when trash clogged it. Getting it started again with the water 15' down the dam was tough. Finally got it drained then had to use a pump to keep the water out while working on the dam. It was a hassle.
I put a drain in my lower pond after that experience. If you ever have to drain to repair or start over it sure makes it easy. Just leave the drain open while you work.
jim--i put a 8"siphon pipe and a runaround on my pond--both were needed earlier this spring and worked o.k. for overflow that's different from draining though-- i also put a 4" pvc (with gate valves on each side of dam) as a drain pipe about 1 1/2 ft off bottom thru the dam in the event i ever needed to drain it totally which unfortunately due to pond leaking i have had to do so and may have to do again so there is something to be said for being prepared in that event--that said my pond height is about 12 or so ft at it's deepest so you may need somthing more substantial. in draining my pond we siphoned down to about 4ft and siphon stopped. used drain pipe to drain all but 1 1/2 ft (if installing drain pipe you may want to consider not placing it directly on bottom to allow some silt to settle in)--to finish getting water out it still took about 20 hours of 3" trash pumping. just some thoughts. i figure my drain pipe will outlive me and if not then can pack it with concrete if i ever have to. best advice is be sure to use a contractor you can trust and find out all you can about pond draining in case you need to--i never realized how much water 1 1/2 ft over more than an acre until i started pumping it. i'm with Ric on this--if you ever need to drain you'll sure be glad you have one. also if you use pvc/gate valves lube them when installing--i had lubed mine well with a silicone grease when i installed it--- 1 yr later they worked great --large pvc gate valves sometime are difficult to work--when i closed it back off i lubed it again. i'd be really careful working and opening a drain valve 4" or larger with much water in pond--unbelievable suction.
I know absolute beans about this issue, but I am digging the drain idea, if and that is a BIG if, it's done right...
Just one other thought.
Mike Otto has been in the business of building dams a long time & he is a "pipe through the dam guy". That settled the question for me.
Jim
welcome to the forum This is the best place to be when you want to have some fun and learn about ponds.
Use plastic not steel.
When you install any pipe make sure the dirt is packes around it well use a anti-seep collar.
All dams seep and it shows up at the pipe most of the time.
Make sure the "Plastic Pipe" is HDPE, if you use CMP, make it BCCMP, but the HDPE will last much much longer, around 50 yrs.
heavies
Welcome abord.
Glad to have you.
What does the letters HDPE--CMP--BCCMP stand for.
High Density Polyethylene
Corrugated Metal Pipe (?)
Bituminous Coated Corrugated Metal Pipe (?)
A properly installed pipe through the dam is worth it's weight in gold in my opinion. I've pumped a lot of water and lost a lot of sleep worrying about rain. One good pipe = lot's of sleep and your back playing in dirt and not the water.
I installed an 8 inch siphon after the fact in my big pond (@ 17 acres?). In about two weeks, will start construction of another smaller @ 4 acre pond and an @ 2 acre pond renovation (drained six years ago? by cutting the dam). On the 2 acre pond, I will only have a pipe through the dam. On the 4 acre, I will have a pipe through the dam so can leave dry and help drain, I will have a siphon going over the top (trenched in; but well compacted) for primary water control / draining, and an extra pipe as a backup overflow. A little overkill; but think that will handle any rains without a "real" spillway - putting driveway across dam. Decided to go with drain pipe in bottom so have option to easily drain completely and to leave dry (looking at possibly building new house there and starting family some day). My experience with siphons has been good. My contractor won't put the pipe through the dam. He has had bad experience and doesn't trust them. My local biologist is a fan of drains as are most fish guys with whom I've talked. We'll going to install it ourselves and use plenty of anti-seep collars.
Rangersedge
Good work--There is no such thing as over kill when it comes to, getting rid of the water.
You will be glad you put a pipe in that will let you drain the lake if you want to. You may never use it- but when you want it you will be glad you did.
Do not be affraid to buy some material to pack around the pipe if you need it. It will make the job easier and let you sleep better at night.