Building Lake Corona

[ovrszd]

Another plus for your overflow design choice.

Any time you have a structure through a dam below water level you compromise the integrity of the dam. This design totally eliminates those kind of problems. Now there is no place for water to seep and potentially wash out the pipe.

There are literally hundreds of structures here in my County with straight thru overflow pipes. I haven't heard of or saw any that required repair.

Once I saw one that got plugged at the upper end during a torrential rain. Took several days for the structure to finally lower back to static level. I heard it had a large turtle wedged in the opening.

 

[EddieWalker]

The 2 big advantages to this type of overflow system are that you are not running a pipe through the dam. It is almost impossible to stop water from eventually leaking along the path of that pipe. With the entry into the pipe at the bottom of the pond, it will pull silt with it, and in theory, keep the depth of the pond, or at least the area around the pipe, at the same depth.

 

[Jim Nelson]

I'm not sure if they are a problem there but where we live every time you bury a pipe the gophers will soon tunnel right beside it and cause problems.

 

[jk96]

So to drain the pond you close the vent and wait for a rise in pond level to create a siphoning effect.

You can drain the pond at anytime by simply capping the outlet and filling the pipe with water at the T. Close a shutoff valve at the vent elbo so you can create the airlock and open the outlet to start the siphon. No need to wait for rain.

 

[pmsmechanic]

There are literally hundreds of structures here in my County with straight thru overflow pipes. I haven't heard of or saw any that required repair.

Once I saw one that got plugged at the upper end during a torrential rain. Took several days for the structure to finally lower back to static level. I heard it had a large turtle wedged in the opening.

We have lots of structures too but with a six foot frost line every year there are issues. I used to work for an irrigation district. It was not uncommon to have 5-10 washouts a year from frost. Most irrigation dams in this area have lowered water levels for the winter. It takes the strain off of the structures.

 

[ovrszd]

You can drain the pond at anytime by simply capping the outlet and filling the pipe with water at the T. Close a shutoff valve at the vent elbo so you can create the airlock and open the outlet to start the siphon. No need to wait for rain.

Oh, of course Jeremy. I'm kinda slow sometimes!!!! I get that now. Sorry for the confusion. Duh.....

 

[ovrszd]

I'm not sure if they are a problem there but where we live every time you bury a pipe the gophers will soon tunnel right beside it and cause problems.

If the structures here are government subsidized thru Soil Conservation Department they require a "seep collar" on the pipe. It's a 3ft square piece of sheet steel with the pipe going thru the center. Located10-15ft from the upper end. Stops varmits from burrowing along the pipe and causing a leak.

 

[ovrszd]

The 2 big advantages to this type of overflow system are that you are not running a pipe through the dam. It is almost impossible to stop water from eventually leaking along the path of that pipe. With the entry into the pipe at the bottom of the pond, it will pull silt with it, and in theory, keep the depth of the pond, or at least the area around the pipe, at the same depth.

I don't think I can agree with the silt theory. I think what you'll eventually have is a plugged pipe. Especially in a condition like Jeremy's where his lake is surrounded by trees which will dump truck loads of leaves in the lake each Fall. They sink and settle on the bottom.

 

[dieselscout80]

I don't think I can agree with the silt theory. I think what you'll eventually have is a plugged pipe. Especially in a condition like Jeremy's where his lake is surrounded by trees which will dump truck loads of leaves in the lake each Fall. They sink and settle on the bottom.

On our pond the siphon intake in the pond has a elbow the runs the drain back up with perforated pipe to keep it from silting in and getting plugged rather than being horizontal.

We also have a seperate drain pipe with a valve that can be opened to drain the pond with the same type elbow and perforated pipe.

The pond is one acre and the drain pipe and siphon are 6" PVC pipes.

 

[ovrszd]

On our pond the siphon intake in the pond has a elbow the runs the drain back up with perforated pipe to keep it from silting in and plugged rather than being horizontal.

Similar to a riser in a terrace. Good idea. As the bottom plugs it will simply draw water from a higher location.