Private Sewer Laterals: What Is a Private Sewer Lateral and How Does It Work?

Most homeowners only think about where sewage goes when there’s an unexpected problem. When that problem involves your home’s sewage system, chances are good that you’ll be learning about your private sewer lateral (or PSL) for the first time.


What is a Private Sewer Lateral?

A private sewer lateral (PSL) is the pipe that connects your home’s plumbing to the publicly-owned sanitary sewer line, usually located under your street. This crucial pipe carries all of the waste water from your home to the sewer, including everything washed down your sink or flushed down your toilet. From there, sewage is transported to a treatment facility. 

Sometimes referred to as “side sewers,” private sewer laterals consist of two main parts:

  1. The upper sewer lateral – The length of pipe closer to the home, including the area from the building cleanout to the sidewalk area.
  2. The lower sewer lateral – The length of pipe closer to the street, including the area from the sidewalk’s curb cleanout to the public sewer main.

Who is Responsible for a Sewer Lateral?

As the PSL term may suggest, a private sewer lateral is the responsibility of the private property owner. In many cases, a homeowner is solely responsible for the upper lateral connection (in Alameda, Albany and Berkeley, CA, for example). However, in many locations in the Bay area (Oakland being one), property owners are responsible for both the upper and lower lateral.

What Are Common Private Sewer Lateral Problems?

The condition of your private sewer lateral will determine where your home’s waste water goes, as well as whether or not ground water and/or rain runoff is allowed to enter the pipe.

Pipe failure usually comes in the form of cracks or blockages in the pipe. Common causes of sewer lateral failure include:

  • Natural erosion from the wastewater
  • Pipe corrosion, calcification, and scale build up
  • Shifting soil
  • Tree root intrusion

As a sewer lateral ages, it becomes more vulnerable to breakage. The average lifetime of a private sewer lateral depends on the material used to construct the pipe. Clay pipes are the most common, but the old-style hub and spigot joints fail, causing the pipeline to break. Today, cast iron is a common sewer lateral material, and should be expected to last about 30-50 years. Another material, high-density polyethylene (HDPE), is now widely used in the industry, as it offers durability, low cost, faster repair, and 100+ years of useful life.

Common problems caused by a broken private sewer lateral include:

  • Sewer backups
  • Contamination of your soil and local creeks from leakage
  • Excess wastewater being polluting local bodies of water
  • Raw sewage overflow caused by water intrusion and root growth

What Are Environmental Requirements for Private Sewer Laterals?

There are serious environmental risks associated with broken private sewer laterals. Exfiltration failures cause wastewater to flow out of the pipe and into the ground where it can threaten drinking water supplies. Inflow and infiltration failures are a more common problem, however. This occurs when rainwater and/or groundwater is allowed into the pipe. In fact, this issue is so common that the excess water can overwhelm a community’s sewer treatment system, which causes overflows and backups that force untreated sewage into yards, streets, or nearby bodies of water (such as the San Francisco Bay).

For this reason, an Environmental Protection Agency (EPA) ordinance requires private sewer laterals to be certified. The East Bay Municipal Utility District (EBMUD) created a PSL Compliance program in 2011 that impacts our communities. Learn more about the EBMUD PSL Compliance here.

How to Fix a Broken Private Sewer Lateral?

If there are sewage issues with your home but you’re not sure that your private sewer line is the culprit, a sewer video inspection may be a good first step. This procedure diagnoses the line (a requirement for EBMUD PSL Certification) and can tell you if your line could pass a pressure test or not—before you test the line, wasting valuable time and money. 

sewer line video inspection is the only way to properly confirm the condition of your sewer line. The camera inspection can identify specific problems, including blockages that should be removed via power snake or hydrojet. After an inspection, you will know if your sewer lateral needs to be replaced.

Contact Pipe Spy for Private Sewer Line Replacement

Once you confirm the need for sewer lateral replacement, we recommend partnering with a company that can perform trenchless sewer line repairs. The pipe-bursting technology employs a nonintrusive process in order to fix your sewer lateral with minimal inconvenience, disruption, and cost.

Pipe Spy was an early adopter and advocate of trenchless pipe bursting, and we’re proud to offer our services to customers throughout the East Bay area, including video inspection (the cost of which can be credited toward a subsequent sewer lateral replacement). We also use HDPE pipe in all of our trenchless replacement projects, helping to ensure that your pipes won’t need to be replaced again during your lifetime.

Learn more about Pipe Spy’s video inspection and trenchless sewer replacement services, or contact our team to discuss your project and request more information.