Check valves....back flow from bog?

[Mmathis]

Need some help deciding a course of action when I get to the the bog plumbing.

Bog will be above ground. Pump is submerged. To prevent back flow from the bog, do I need a check valve, and if so, what is the best, most reliable kind to use?

For the Skippy, I used this system [see drawing] and there was never an issue with back flow, so never had to have a check valve.

 

[mrsclem]

TM- I installed a flap style check valve on my bog. I have the same set-up as you with my pump in the pond pumping up to my bog that is above ground. I tested it and it did not stop the back flush. The problem with using the fitting you use on the skippy is that the water will flow up instead of going to the bottom of the bog. I took the cheap route and drilled a 1/4 inch hole on the pipe going to the downward pipe on the bog. It is on the bottom so it doesn't spray up. Tested and it works!

 

[Mmathis]

@mrsclem Do you mean something like along the red-circled area in this drawing?

 

[addy1]

I used this for our stream pond piping, been working for a few years now

http://www.lowes.com/Search=pvc+che...10051&N=0&newSearch=true&Ntt=pvc+check+vavle#!

 

[tbendl]

Ohh, so you could use that at the top of the PVC piping going into the bog where your water flow tube from the pond is and that would keep it from backflowing into the pond?

 

[mrsclem]

That is the valve I installed. Not sure why but it did not stop the backflow.

 

[tbendl]

I forgot about the back flow issue when I installed my PVC. Turned off the pump last night and sure enough it drained most of the bog overnight. Can I just drill a pinhole in the PVC at the water level of the bog to stop the back flow from happening?

 

[Dirty Dawg]

I'm not a fan of check-valves, I never trust them to actually work.

Planning on one of these or similar for my bog infeed plumbing.

Called a "cheater vent"

http://www.homedepot.com/p/Oatey-1-1-2-in-ABS-PTC-In-Line-Cheater-Vent-39012/100204205

Of course, the uphill bog feed pipe will still drain back to the pond, but no big deal.

 

[tbendl]

But DD since I already have my plumbing done, wouldn't drilling a tiny hole the size of my smallest drill bit, be enough to break the pressure from it back flowing? I can put one of those thingamabobbers in but I'd have to take my bog plumbing apart to do that.

 

[Dirty Dawg]

But DD since I already have my plumbing done, wouldn't drilling a tiny hole the size of my smallest drill bit, be enough to break the pressure from it back flowing? I can put one of those thingamabobbers in but I'd have to take my bog plumbing apart to do that.

Oh I'm pretty certain that small air hole you are planning will work just fine. It doesn't take much air to break the siphon action from what I've seen in other situations.

 

[tbendl]

My pond doesn't suck that much to begin with. It is a fairly low GPH pump and a small diameter PVC so I hope that will work. I guess I can keep enlarging the hole if it doesn't until I get the suction to break.
Thanks DD

 

[dieselplower]

Ive got to ask... if you drill a hole in the PVC, would the water not leak out of it while the pump is running and water is flowing to the bog?

 

[tbendl]

I've got to answer. Yeah I would assume so but if I do it on the inside of the bog at gravel level and do the smallest hole possible, I would hope that it wouldn't spew that much water or make me lose that much water pressure going up. I know, I did the assume thing.. What are your thoughts Dieselplower?

 

[dieselplower]

Well doing it inside the bog seems like a good safety measure! I think it would squirt water out the hole a bit but there is only one way to find out. For whatever reason I was thinking the hole would be outside of the bog.... Doh

 

[tbendl]

Obviously it was your faith in my brilliance. Hahaha. True, I was just hoping someone else had done this before I start drilling holes in my PVC. Oh well I am willing to go where no ponder has gone before.