Water main

[bannerd]

So we're in a pickle, the water main from our source to the house was found today at the job site. Winter will be here in no time and frost will most likely freeze the line.

The water main is 2" ID and hooks to a spring that flows 24/7. The entire spot for the house foundation was excavated and the footings/walls are built over the water main. Oddly enough the water main from our trailer goes completely away and then must loop back. Was not where we thought it was from the previous owner. To make sure it was not old pipe I ended up having the wife flush all the toilets and sure enough the vibration from the pump went through the pipe.

The issue is, we have about 7ft of pipe that is 2ft below frost and then dive bumbs about 9ft below frost. What to do? I thought about putting a large pile of leaves over the 7ft area and then staking a tarp there. We already insulated the pipe with fiber glass wrap... any other ideas?

 

[wasfuzz]

Foam board then straw then tarp?But you are 2 ft below frost already - leave a tap dripping! Can you abscess all sides of the pipe if so maybe pipe insulation then foam then straw?

 

[bannerd]

Foam board then straw then tarp?But you are 2 ft below frost already - leave a tap dripping! Can you abscess all sides of the pipe if so maybe pipe insulation then foam then straw?

Yeah, we dug down the 2ft where the pipe was and use frostking wrap the pipe and then layed some roxul in the area.

Not sure what else we can do, we have straw on it and the wife put large piles of leaves. (4ft piles).

 

[matt_i]

I would build a box out of 2x4s and plywood. Then cover with 2" pink foam, use the blue Loctite construction adhesive for foam to assist. PLace inside, a 60W incandescent light bulb. I think the Roxul is a great idea to help seal it to the ground.

The leaves should go now that you have a heat source plus the organic material is undesirable anywhere you eventually want concrete (if I understood the placement correctly). I would check it thru a couple of cool overnights, if its warm first thing in the morning you should be good. Could also place an exterior dial-type thermometer inside as well for a more quantitative result. The light bulb can be upgraded to a 100W or doubled to 2x 60W. Despite their relatively inefficient light production, they make nice little heaters.

 

[Paperman]

Its 2' below the frost line or 2' below grade? You say it flows 24/7? Insulation is worthless when wet, Can you trace it with heat tape? Good quality heat trace will stay in place for years without issue. What is the pipe material? Can you get to both ends? I ask for if it does freeze they make pipe thaw rigs for metallic pipe that work very good.

 

[Chris705]

Can you explain your concern a bit further? I thought after reading a few times that your water main is 2' BELOW your frost line? What is the concern? Is there some issue with a vertical pipe below the frost line that potentially freezes that I don't know about

 

[bannerd]

It's 2ft in the frost zone, sorry about that. We have a 5ft frost level in my area. Good thinking on the heat tape, never heard of that stuff but definitely doable. The pipe material is polyethylene so metal wouldn't work too well. We use to do that with copper and a generator to unthaw frozen pipes back in the day.

 

[GSRinmyCRX]

if you can leave the water running in your house the pipe will have a lot harder time freezing. maybe install a T with a valve before your pump so that your pump doesn't get worn out.

moving water isn't frozen so keep it moving.

Levi

 

[gungatim]

I would use heat tape on a timer. find a mobile home dealer or parts place locally, they all use them.

 

[Falcon67]

Can you explain your concern a bit further? I thought after reading a few times that your water main is 2' BELOW your frost line? What is the concern? Is there some issue with a vertical pipe below the frost line that potentially freezes that I don't know about

Sounds like they are digging the foundation for a house, taking footers down below the 5' frost line and in the process uncovered the water main leading from the spring.

Looking at Catskill NY long range - Albany similar - , doesn't look like "upstate NY" will get below freezing until mid November or near Thanksgiving - seems like things should be farther along well before that to limit exposure?

 

[kbs2244]

Remember the" frost line is a worst case thing.
A power co lineman I know said the only time they got near it was replacing poles along rural roads in Feb of a record winter.
He called houses "low temp ovens" and said the frost rarely got within 2 feet of a heated basement wall.

 

[Chris705]

Similar to Matt's thought in post #4, two 4x8 sheets of 2" rigid (to cover an 8x8 area).....a few heavy stones to hold them in place and then covered with your leaves and a poly tarp....heat from the earth will keep that area warm enough. That is if this is a temporary solution....I assume you wil correct the depth next spring?.

 

[matt_i]

One more thought...if you do some reading on the HUD design guide to Frost Protected Shallow Foundations (FPSF) I get that 2" of R6 insulation is as good an insulator as a foot of generic fill dirt.

It does require some extra prep with crushed stone to keep ground water from wicking via surface tension and also some vertical wings or a wide span. My quick thought is if you designed the waterline as if it was part of a footing for an unheated building for your climate, you'd be OK. There are design guidelines as to how far the insulation must extend outside of the foundation, if you take that resulting number and put it on both sides of the waterline then you're going to be in good shape, no heat sources needed.

In my earlier post I was assuming you needed temporary cover due to the application of leaves.

This is a .pdf link to the HUD design guide

https://www.huduser.gov/portal/publications/PDF/FPSFguide.pdf