Photo Diary of 1/2 acre pond construction

[Larry_Van_Horn]

Don,
We used 4" sched 40 PVC. There are 2 outlets at lower levels so water can be drained if I am so inclined. I currently do not have a trap over the top, but that isn't a bad idea. Good luck
Lar

 

[rlk]

OkeeDon and Larry, when I built my pond, I used a 6 inch plastic pipe for the overflow. Then I took a 12 inch plastic pipe, and put it down over the 6 inch pipe. I put rebar through the top of the 12 inch pipe to hold it about 2 feet off of the bottom. The 12 inch pipe sticks up a few inches higher than the 6 inch pipe. The reason for doing this is two fold:

1. Apparently water on the bottom of the pond does not have much oxygen, so you want to draw that water out vs. water from the top. Pressure will push water from the bottom into the 12 inch pipe and up the sides between the two pipes and into the top of the 6 inch pipe to be drained.

2. Since the 12 inch pipe is a few inches taller than the 6 inch pipe. the 12 inch pipe acts as a screen to prevent debris, fish, turtles, etc. from entering the 6 inch pipe and clogging it. Also, in case of a major storm, water will run over the top of the 12 inch pipe into the 6 inch.

My description may be a little hard to understand, but basically you have a 6 inch pipe inside a 12 inch pipe to draw water off the bottom of the pond. I'm going to try to attach a picture that will show the larger pipe sticking up above the smaller pipe.

Took me a little while to find 12 inch plastic pipe, but finally found a company that had some. I needed a 10 foot piece. They sold it in 20 foot lengths, but had a piece that was damaged. When I went to get it, they gave it to me just to get it out of their way. Very nice people to deal with.

One caution is don't use 12 inch pipe that has double walls. Water will get between the walls, and it will be almost impossible to lift it should you ever have to remove it.

Bob

 

[rlk]

That picture did not show the pipe too well, so let me try this one. Hopefully in this one you will be able to see the rebar holding the large pipe over the smaller pipe.

 

[jinman]

What is holding your 12" pipe down? is it just held over the 6" pipe by its own weight? I understand your description of how the flow works, I like the hydrostatic method of pumping water off the bottom.

 

[rlk]

Yeah, it is held down by its own weight. That 12 inch pipe is heavy. This 10 foot piece probably weighed 60 - 70 pounds.

 

[Larry_Van_Horn]

Bob,
Nice idea! I hadn't thought of this as a way to draw water from the bottom. Wish we had exchanged 3 months ago.
Best,
Larry

 

[have_blue]

</font><font color="blue" class="small">( I hadn't thought of this as a way to draw water from the bottom. Wish we had exchanged 3 months ago. )</font>

Larry,

All you need to expel water from the bottom is a single pipe. The lower end should be near the bottom, the upper end should exit the pond on the maximum level you want the pond to be. When the pond gets even a little over full, it drains from the bottom up. A foot valve (usually just a cheap flapper or ball valve) can prevent water from flowing the wrong way in case of a real flood.

 

[OkeeDon]

Good idea. Wish I could use it. I may not even have enough vertical room to put an elbow on the inflow side of my overflow pipe - it may just stick out horizontally from the bank. I need the outflow side to be as high as possible in the highway swale, and there isn't much elevation change -- maybe 12". At a minimum fall of 1/8" per foot, and about 60' or so between the pond and the swale, I'll need 8" of that elevation change just for the fall of the drain. The drain pipe will be just under the ground level most of the way -- I did have the pond bank built up very slightly, maybe 8" above ground level at that point.

This past summer, the water in the swale rose to overflowing into my property and to about the level at which my overflow would be set. At that point, the drain becomes useless and all I can do is pray for it to stop raining...I expect there will be times when the pond overflows, which is why we used the dirt from the pond to build up the area around the house by 30", and why the house will be on a perimeter foundation another 24" above that. Local code calls for the floor elevation to be 18" above the crown of the road.

It's no fun dealing with flat land; as my contractor kept reminding me, with a wry sense of humor, while we laid out the drainage plan, "Water doesn't flow uphill."

 

[DAP]

Re: Picture 16: Last for now

At least here in NY, a lake technically has a waterway entering and exiting from it's body.

Now I have a 1/3 acre 'pond' on my property that technically is a lake as it meets the above critieria as far as the EPA is concerned.

I'm sure were a pond large enough it would be referred to as 'the Lake'.

My 2 centavos. /forums/images/graemlins/smirk.gif