How Deep Your Sewer Line Should Be — And Why It Matters

Sewer pipe in ground trench.How To Avoid Frozen Pipes in Pennsylvania

Digging your sewer lines to the proper depth is essential for safely and swiftly removing wastewater from your home. In Pennsylvania, the frost line is 44 inches beneath the surface, and any sewer lines installed above this level are at risk of freezing and bursting, causing costly damage.

When it comes to sewer line problems in Pennsylvania, frozen pipes are a leading cause of damage. We recommend that every homeowner verify to determine how deep the sewer lines on their property were placed.

Why Sewer Line Depth Is Important

The average frost line depth in Pennsylvania is 44 inches. At this depth, groundwater and any water in your sewer lines will freeze. Generally, the colder a region gets in winter, the deeper the frost line.

sewer line depth below the frost line

During especially long, cold winters, these depths can drop far below what’s considered normal. In addition to changes caused by air temperature, frost lines can rise or fall based on soil type and moisture content.

Not only will water freeze above the frost line, but as it freezes, it causes the soil to heave. This is because water expands 9% in volume when it freezes, forcing the soil out of position. Anything positioned within or above the frost line will shift. This includes building foundations, footings, and of course, sewer lines.

Don’t let your sewer line freeze this winter! Call Andreas Plumbing, Heating, & Air Conditioning to replace your home’s sewer line and avoid potential damage.

Factors That Affect Sewer Line Depth

Most communities in Carbon County and throughout Pennsylvania require sewer lines to be installed well below the frost line. This means installing it at least four feet below grade. However, that’s not always the case, and many factors can affect the actual depth of the line, including:

  • Climate: As already stated, climate can significantly impact sewer line depth. In Alaska, the frost line is as low as 100 inches.
  • Regulations: City and county regulations can vary greatly across every state. It’s imperative for homeowners to confirm what the regulations are within their community.
  • Main sewer line location: Proximity to the main sewer line is another factor influencing the installation depth. Lines closer to the main sewer line will typically be higher than those farther away. Sewer line depth is determined by the required gradient to reach the main sewer line, and if it’s too shallow a slope, sewage backups become a problem.
  • Soil type: Silty or clay soils are the most likely to freeze. This is because the porosity of these soils traps moisture, which can then freeze.
  • Age: Regulations governing sewer line depth can change over time. This means that homes built 100 years ago may have sewer lines that are much deeper or shallower, depending on the community, than homes built five or 10 years ago.

Schedule Sewer Line Services in Carbon County

At Andreas Plumbing, Heating & Air Conditioning, our sewer line specialists are always prepared to provide the sewer line installation, sewer line maintenance, and sewer line repairs homeowners in Carbon County depend on.

As a fourth-generation, family-owned business, we’re committed to our community and the needs of our clients. Our technicians adhere to strict safety and quality standards, and we guarantee the durability and reliability of our services.

When you choose our team to service your sewer lines, you’ll always enjoy:

  • 24/7 emergency  services
  • Honest, upfront pricing
  • Clean and tidy workspaces — we leave no mess behind
  • Strict adherence to safety and all applicable regulatory requirements
  • Licensed and insured technicians

Contact Andreas Plumbing, Heating & Air Conditioning at (610) 377-5261 to learn more about our company and request sewer line services in Carbon County.