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Are you putting your Forestville home on the market or planning on a major remodeling?

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On November 17, 2017, the Forestville Water District Board of Directors approved and passed Ordinance 61, requiring all properties within the Forestville Sewer District to have a Private Sewer Lateral (PSL) inspection following a sale or remodel event, effectively January 1, 2018 (Ordinance #61-attached).

Why is the district requiring inspections? 

During the 2017 inspection of the sanitary sewer collection system, it was discovered many of the PSLs show signs of damage, wear and/or leaking. Lateral sewers impact the environment and local waterways, which means it’s important to keep them in good working condition. A leak or spill can send human waste straight into local groundwater and California waterways and become an environmental and public health disaster. Everyone has an obligation to keep their sewer lateral in good working order and that includes residential property owners. Ordinance #61 is aimed at reducing the inflow/intrusion that is added to the collection system through these PSL defects.

What is a Private Sewer Lateral?

A private sewer lateral is an underground pipe that conveys wastewater from your building to the sanitary sewer system. Typically the private sewer lateral goes from your building to the sewer main in the street. 

If you live in the Forestville’s Sewer District limits and access the public sewer, you might wonder why you need an inspection. Shouldn’t the sewer be the district’s responsibility?  

While the sewer main (hidden under the street) is the district’s responsibility, your private sewer lateral (connecting your home to the main) is your responsibility as the property owner. You own the land that the private sewer lateral operates on, and therefore you’re responsible for making sure it directs your waste to the sewer main.


You must work with a licensed-certified inspector

A run-of-the-mill home inspector, such as the one hired by buyers, won’t work. A licensed-certified plumber and inspector will have the experience and the specialist camera equipment needed to access the private sewer lateral and check it appropriately. Ordinance 61 (provided below) outlines what the inspection needs to include, feel free to provide a copy to the licensed-certified inspector. 

And remember never attach your downspout drain directly to your sewer.

Ord. 61 - Sewer Lateral Adopted 11.14.17.pdf

Please reach us at if you cannot find an answer to your question.

Q: How do I know if there is something wrong with my private sewer lateral? 

A: Private sewer laterals are underground so most people won’t see a problem at the ground surface. Older private sewer laterals and laterals in the vicinity of trees or large bushes are more likely to have problems. A local plumber can inspect private sewer laterals by using a video camera to look for cracks, joint separation, root intrusion, blockages, and pipe sags.

Q: How often should I perform maintenance on my private sewer lateral? 


A: Private building lateral maintenance depends on several factors including age of pipe, pipe material, and site. It is generally recommended to have older private sewer laterals inspected and cleaned every couple years. Most plumbers can inspect and clean a private sewer lateral.

Q: What are the consequences of not maintaining my private sewer lateral? 


A: Private sewer laterals develop defects over time and contribute to sewer backups into the building, environmental pollution, more expensive private sewer lateral repairs, and more expensive costs for the local treatment plant. In some circumstances, the property owner can be liable for any environmental damage and the governing regulatory agency could be forced to terminate sewer service until the private sewer lateral is repaired.

Q: What is inflow and infiltration? 

Inflow and infiltration are terms used to describe the ways that clean groundwater and/or storm water flow into the wastewater system, due to cracked sewer lines, leaky manholes or through erroneously connected storm drains. Most inflow comes from storm water and most infiltration comes from groundwater.

Inflow is surface water that enters the wastewater system through improper connections, such as catch basins, yard, roof and footing drains, downspouts, groundwater sump pumps, and through holes in manhole covers. Inflow typically occurs as a result of storm events. Peak inflow occurs during heavy storm events when storm sewer systems are full, resulting in backups and ponding.

Infiltration is groundwater that enters the wastewater system through holes, breaks, joint failures, connection failures and other openings in the pipe. Infiltration amounts often exhibit seasonal variation in response to groundwater levels. Storm events can trigger a rise in groundwater levels and increase infiltration flows. The highest infiltration flows are observed following significant storm events or following prolonged periods of precipitation when the ground is saturated with water.