Pond Boss Forums INTRO Questions & Observations Pond Drains?

I am currently in the process of purchasing piping for my pond discharge and was curious if anyone has a drain for their pond? I was planning on using it at the inlet to a riser T to drain the water from the pond if need be. If so what type is recommended? I was looking at an 10" AMC-10 Canal Gate W/24" SB Frame from AMC valves, also looking at the PVC style knife gate valve. The links to both products are as follows: http://www.aquamasters.com/Knifegates.htm
http://www.amvalve.com/amc-10.htm
Any info would be geatly appreciated.

Hey B-S...
We installed a drain system, but it was the basic horizontal pipe thru the base of the dam. We did install a 6" victaulic brand butterfly valve. Some good discussion and details are within this second thread link.

To each his own but I've seen too many of those drains not work as anticipated and I've seen the pipe through the dam create a leak even with a collar. I prefer a good ol' trash pumpto drain a pond. I recently drained a 3/4 acre pond that was about 1,000,000 gallons in week with one.

I also don't have an overflow pipe in the dam. I use what is labeled as an "emergency overflow" which is a rock lined channel on top of the dam on this pond, and to me it's a good example of the "Keep it Simple Stupid" principal. Never had a problem with it and can't see where I would. I do have a pipe at the end of this channel that sits on top of the ground that drops the water into a ditch though. Let me know if you want pictures.

Cecil is not alone on his drain posture. There are a number of Pondmeisters that see drains as nothing more than a potential for failure. This is a respectable attitude. OTOH, tho, there are many that were installed with the best practices and they function fine. Also, I remember a conversation I had with Mike Otto when I was preparing to construct the drain and dam for out project. Amongst the numerous words of wisdom he imparted, he did state that "all drains leak". It came with all the dotted "I's" and crossed "T's" for proper drain installation. I take this to mean the obvious "do it correctly and it will be fine".

Sadly you can't always find alledged pond builders that are as knowledgable as they should be. The one that built my first pond didn't even bother to put a collar on the overflow pipe. Of course it was just a matter of time before the water followed the outside of the pipe. I had him rip it out and I put in the emergency overlow. He also thought I was crazy when I mentioned how important a core trench was in my second pond. When I was gone he just piled soil on top of sod at the dike and it seeps there to this day. Needless to say I found someone else for my third and fourth ponds.

Cecil
If you have pictures available of your emergency overflow can you post them here or if they are elsewhere on here post a link to them. My thought is if I had the oportunity to pull water out the bottom it would also pull out sediment that would be on the bottom. My concern is to not have a problem down the road with it. Dep recommended a drain but would not recommend a type. The average rainfall map I got from DEP is putting my area at 35-40 inches a year on average so I am definitly going to need a spillway also. Here is the link if anyone else is from PA and looking for rainfall amounts: http://www.erh.noaa.gov/ctp/hydro/normalprecip.php

Cecil
If you have pictures available of your emergency overflow can you post them here or if they are elsewhere on here post a link to them. My thought is if I had the oportunity to pull water out the bottom it would also pull out sediment that would be on the bottom. My concern is to not have a problem down the road with it. Dep recommended a drain but would not recommend a type. The average rainfall map I got from DEP is putting my area at 35-40 inches a year on average so I am definitly going to need a spillway also. Here is the link if anyone else is from PA and looking for rainfall amounts: http://www.erh.noaa.gov/ctp/hydro/normalprecip.php

I'll take pics tomorrow.

I'm a novice but it seems to me that there is no lunch that can be had without some cost. If your primary spillway is a pipe there are issues with leaking. If your spillway is made of earth it can erode and fail during an unusual rain event. Did I get that right?

Also for the peanut gallery; Are siphon systems more or less prone to leakage?

A syphon should be less prone to leaking as it does not run through the bottom of the dam.

I respectfully disagree. I have no erosion problems whatsoever with my overflow drain. In fact if anything I have to clear grass and weeds out of it periodically. I suppose that is the trade off.

I hope to post pics later today. I need to take a lunch nap, then lower my fish cages deeper for the winter and run some errands. Then get back ot taxidermy to pay the bills. Somewhere in there I will take pics and upload them here.

The past few years I have observed several ponds built in our area, and none have "through the dam piping".
Most have siphon systems and/or emergency spillways, including ours.

Our siphon systems have handled spring flood conditions without reaching emergency spillway conditions.

Brian:

I fear any bottom drain system that accepted sediment would be prone to settling and blockage in times of low flow.

Theo,
That was one of my concerns with having a drain, the chance it would be covered in sediment when I did want to posibly use it. I have been reading about the amount of sediment that can collect on the bottom of ponds over the years from leaves and other foreign debris ending up in the pond. That was another problem I had seen in the future with the use of a siphon system.
I might be expecting thinks that could happen that may never happen. I am just looking for the safe bet to prevent future headaches.

Brian, a siphon is a primary spillway and drains water every time the pond exceeds full pool even by a small amount. I would think that the inlet would remain clear because of that. That's one of the big advantages of siphon systems, they purge stagnant bottom water regularly as new water fills the pond.

My siphon system purges bottom water and goes through the bottom of the dam...........no leaks after 5 years so far. My bottom drain collar is about 12" above the absolute deepest area of the pond. Have had no problems with sediment clogging the drain ... matter of fact I believe it actually cleans around itself when purging IMHO.

I can't remember where I read it within this forum, but convincing arguments by respected sources were put forth stating that appreciable sediment removal by any drain system was not going to occur. Rather to focus on the removal of the bottom water, a product of lesser quality than the balance of the pool.