Can water intake poly pipe freeze under soil, in water?

Users who are viewing this thread

Patty Bates

New Member
Messages
10
Reaction score
0
Points
1
Location
Ottawa, ON
Hello,
At my cottage I have a 1-1/4" black poly pipe for lake water intake. It leaves the cottage, runs 4 feet underground and enters the lake. Where the pipe enters the water at the shore, it's buried under sand, but definitely less than 4 feet deep (probably 1 to 2 feet deep). As the lake is freezing over, I'm wondering if it's possible for the ice on top of the lake to freeze the soil enough to actually freeze the poly pipe (ie; can the thickening lake ice "penetrate" and freeze the soil)? I've tried to research this for quite some time but can't come to a conclusion.
Here is an image to better explain.

patty-bates-01.jpg


Thank you,
Pat
 
Last edited:

Terry

The Plumbing Wizard
Staff member
Messages
29,942
Reaction score
3,458
Points
113
Location
Bothell, Washington
Website
terrylove.com
Most local codes will post what the amount of cover should be.
In the Seattle area they want 24"
I have heard some places want as much as 60"
 

Patty Bates

New Member
Messages
10
Reaction score
0
Points
1
Location
Ottawa, ON
Thanks Terry for answering so quickly. Can you explain what is meant by "cover"? Is that the total depth of the pipe in the ground? Because at some point the pipe has to come out (in the lake) to pull water through the foot valve.
 

Reach4

Well-Known Member
Messages
38,794
Reaction score
4,411
Points
113
Location
IL
I suggest you add "frost line" to your searches.
https://en.wikipedia.org/wiki/Frost_line says the frost line is 5.9 ft in Ottawa.

So your if we amend your question to whether water in the two-foot down/deep pipe is going to freeze in the winter, the answer is yes.

So I think that we would not attribute that freezing to the ice, but rather the cold air above.

A question you did not ask is if there is a way to have that pipe not damaged and still be in good shape come spring. If you want to pull water in the winter, you will have to trench deeper.
 

LLigetfa

DIYer, not in the trades
Messages
7,497
Reaction score
575
Points
113
Location
NW Ontario, Canada
A question you did not ask is if there is a way to have that pipe not damaged and still be in good shape come spring.
When water in a buried pipe freezes, it does so very gradually with the ice displacing the water ahead of where it forms and the poly pipe usually does not get damaged.

If one is concerned about year around water use, then the pipe needs to be set deeper, or insulated and perhaps heat traced. Given that foot valve is mentioned, it is likely not a submersible pump and so a drain-back system is not an option. Even where drain-back is an option, the transition at the water line has nowhere to drain to so needs to be treated the same as a suction line.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks