Hello, My mother has a home that was built 3 years ago. We are in Ohio. The sewer line is freezing up and backing up. We recently discovered that the main line comming out of the house is only burried at 13 inches deep and this is where it is freezing up. The Frost line in our area is 2' 10" and code calls for the line to be at least 3' below the ground. The house is built on a concrete slab. The builder is bankrupt and out of business, and never had a final plumping inspection done on the home. We cant afford to re-run a new line. Is there any type of heating element that can be inserted in the line for a reasonable cost to keep it from freezing.