Bog filter in climate with freezing winter temperatures

[combatwombat]

@addy1: Just had a thought. What is the elevation of your external pump in relation to your bog's water level? Is it higher?

 

[addy1]

My pond is built on a serious slope. The lower edge of the pond the pump is on drops down away from the pond, down to real ground level. First picture, the pump is a bit higher than the water level of the pond, but not much, it self primes without issue.

The bog line goes into the bog over the wall. It right at the level of the pea gravel plus about a inch. The built up berm the bog is on drops down about 6ish feet to the real level of the yard. Sort of second pic. The pump is lower than the bog.

If this makes sense.

Not built as you and @GBBUDD have built with tons of beautiful rocks, everything hidden.

@addy1: Just had a thought. What is the elevation of your external pump in relation to your bog's water level? Is it higher?

 

[combatwombat]

Thanks, Addy. I was trying to figure out if the reason you never have siphon is because your pump sits higher than the water level in the bog. Sounds like that's not it. So, in winter, you pull your pump and leave the end of the pipe completely open with no valve to prevent backflow? And the bog doesn't drain down?

 

[GBBUDD]

That's a bit risky if so .

 

[addy1]

Thanks, Addy. I was trying to figure out if the reason you never have siphon is because your pump sits higher than the water level in the bog. Sounds like that's not it. So, in winter, you pull your pump and leave the end of the pipe completely open with no valve to prevent backflow? And the bog doesn't drain down?

Yes, the pvc pipe goes right over the wall so it is a bit higher than the pea gravel. I had done a hole in the liner, could never get it to stop leaking at the bottom, for the water input. We did also do a drain hole, drain hole fine, water input hole ended up sealing it off.

I pull the pump, the lines are left open. The bog drains down to the water fall rock level and stops. The slightly higher pvc line is probably the reason the bog does not drain down. The pump is definitely lower than the pond and bog due to our slope, worked out great for self priming it.

Been doing this for over 10 years without issue.

 

[BeginnerMind]

As for plans, ideas, pictures, extensive discussions....Did you look at the links I posted back in post #9?
Plenty of info there.

Expansion:
The bog walls should be a bit higher than the water level in the bog, just in case there's any upward expansion or wicking of water off of plants.

A lot of us prefer cutting slits in the pipes instead of drilling holes. I think there's a less change of gravel blocking slits than holes.
Their purpose is to distribute the pond water throughout the bog.

Thank you poconojoe. Yes, I saw the plans and pictures. Thank you very much for sharing.