Home>Discussions>PLUMBING>Keeping incoming water line from freezing
5 posts / 0 new
Last post
Maine Cottage Owner
Keeping incoming water line from freezing

HI Folks,

I posted this a few years ago, but no one replied, and I still have the same question.

I own a small cottage in Maine. In the winter we leave the heat on at 55 degrees, and shut off the main water valve. I also have a freeze alarm that calls me if the heat goes off.

The one area that I am concerned about is the main pipe that enters the house connecting with the municipal water supply.

The house has no basement, it is bulit on piers.

The water line from the street runs underground, then emerges from the ground in the crawlspace under the kitchen. However, it emerges about three feet away from where the pipe actually enters the house. So it comes up about 6 inches, there is a 90 degree bend, and then three feet of horizontal pipe, another 90, then the pipe goes into the kitchen.

It is a copper pipe.

The pipe is insulated with foam, and there is heat tape on the pipe, which we always leave on in the winter. Since this line is before my house shut off, I can't shut the water to it myself.

The problem is, one winter there was a power failure that lasted almost 48 hours, while we were away, so the heat tape was obviously not on.

Everything was fine, but the question is what can I do make this pipe less prone to freezing in case of a longer power failure?

I guess I could have a plumber attempt to reroute the pipe so that it enters the heated space closer to where it emerges, but I am not sure how practical or expensive that would be. It would involved hand digging under a crawl space.

Does anyone make heat tape with some kind of battery back up? Does anyone have a preference for a brand of heat tape?

Should I have the copper replaced with pex? Is it more stable in cold weather?

Other thoughts?


Re: Keeping incoming water line from freezing


Try calling your town water supply dept. (not at their emergency number, but their business number) to advise them of the problem you are having; most of the shutoff valves installed by municipal water suppliers at the curb (called a corporation stop) have a water discharge valve built into them so that when they are turned off, part of the existing water standing in the supply pipe is discharged into the ground; this is to help prevent standing water in the line from freezing & bursting the main water line from the curb stop to the house.

Each of the thousands of local water supply depts around the country have minor differences in the equipment they have installed over the years; some towns also install a homeowner's main valve in the square metal box at the curb; if not, the curb stop valve, as noted, needs a special wrench to operate it; most of them, especially if they're old & have been in the ground for a number of years, are hard to turn & need the muscle of both arms to turn them completely on or off.

Exactly how much water in the line is discharged depends on how the supply pipe was installed--if it was done by a plumber who knew what he was doing, he took the precaution of pitching the supply pipe toward the corp stop, so that most of the water will drain out.

If the square metal box that contains the curb stop valve is not visible near the curb, you will have to take a pitchfork or screwdiriver & probe around the ground until you locate the metal box---dig down & remove the cover & note the valve fitting size so you can obtain the wrench you need to operate the valve.

There is a special wrench that the water co. uses to turn the curb stop, but the water co. usually allows the homeowner to buy his own wrench at a hardware store & use it himself, for exactly this purpose---to prevent winter freezeups & pipe damage.

If the curb stop valve at your location does not have a standing water discharge feature, you may have the option of having one installed by a licensed plumber, or the water dept.; you would probably incur a cost for this, but it may be just what the doctor ordered.

Re: Keeping incoming water line from freezing

What would make a big difference as to what you could do to solve your problem is if you home is above or below the street level.


Maine Cottage Owner
Re: Keeping incoming water line from freezing

Thank you for the replies. Yes, the house is at least somewhat higher than street level.

So, are you saying that the water might drain out by gravity back to the street, depending on the kind of valve they have installed at the street?

I will check with the water authority to see what the options are.


Re: Keeping incoming water line from freezing

If they have the proper curb stop the water will drain back to the street. If they don't or won't let you turn off there valve you could install your own valve beyond there's.


Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.