Hi all,
I have a plastic sewer line recently installed to replace broken clay and due to grading of driveway is now close to 6" below gravel driveway surface. Kansas City Mo so gets cold in winter on occasion. Is there a concern about freezing?
The green pvc they sell looks real thin but so far have been driving over and no problems yet but is that a concern?
Thanks
Mark
the only solution would be to dig it all back up and lower the high end...I think i have more fall than I need between one side of drive to the other, I think I'm about 2 ft deep at low end in like 20 or 25 feet.
When I replaced the broken clay with the new plastic i didn't realize how low the final driveway height would be or I could have used an elbow to get lower on the high end.
I really really really don't want to have to dig it up and redo unless someone says it's totally unworkable as is.

there are a couple of scenarios that you need to worry about.

a partial stoppage downstream of the driveway. this will cause a pool of water to accumulate and this will freeze and keep freezing more water until it eventually blocks the pipe entirely.

a slow dripping faucet or toilet fill valve will allow such a small amount of water to dribble down the drain that it can freeze. this of course will build up and cause major problems.

but the good news is that absent those two scenarios, running water will not freeze.

Thanks for those thoughts Packy.
I also figured out that I can raise that side of the drive somewhat and have the swale more toward the side of drive where pipe is lower.

to meet code the pipe MUST be at or below the local 'frost zone' depth

you are aware that your installation does NOT meet code

? what would you state on a real estate 'disclosure form' for a potential sale ?



you goofed - bite the bullet - fix it

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

with all due respect to my good friend from SC...
i'm not aware of any code that says the sewer exiting the house must be below the frost line?
most septic tanks that i know of are purposely placed high so the water can run downhill to the leaching field.

the only scenario that i can think of that would be forbidden is a pumped sewer (around here they are called "full bore" lines). they have 4" pvc under the streets which are actually under pressure. the connections coming from the houses actually run up hill and are 1 inch PVC with check valves. there is a small cylindrical tank in each front yard that has a strong macerating pump inside.
we as plumbers are forbidden from working on these systems. must be a DPW approved sewer pump company.

Quote

Building drains can freeze inside the building and even outside a drain line that is not below the frost line can easily freeze in some conditions which we outline below. Even if the building water supply piping has not frozen a drain line can freeze. You may first notice the problem when a toilet, sink, or tub simply stops draining.

[www.bing.com]


code be damned - how about we 'good practice' for a bit ?



==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638