Skip To ContentAbout the CityCity ServicesCity GovernmentVisit PasoBusiness DevelopmentVolunteer
City of Paso Robles
DepartmentsCity CouncilAdvisory BodiesPlanning Commission
Wastewater Division Treatment Plant
3200 Sulphur Springs Road
Paso Robles, CA 93446
(805) 237-3865
(805) 237-3886 FAX
Mon-Fri 7am to 3:30pm


Sewage is backing up into my house overflowing from my drains. What should I do?
If these problems occur and you are not using any water outlets, there may be a problem in the City main. Call 237-3865 or after business hours call 237-6464 to request service.

If you are using your household water outlets, turn them off. If the overflowing wastewater stops after turning off your outlets, you likely a problem in your sewer lateral and you will need to call a plumber. There is a cap on the sewer lateral cleanout located outside your home; if you remove the cap it may reduce backup in your inside drains for a short time.

What is a sewer lateral?
A sewer lateral (building sewer) is the privately owned and maintained sewer pipe connecting a building/dwelling to the public sewer main.

What should I do if sewage is overflowing from a sewer structure onto the ground?
If you notice any sewage flowing onto the ground call 237-3865 or 237-6464 to report it. Please give your name and a call back number and note exact location and where the sewage is coming from. City crews will respond to investigate.

I have slow drainage through my toilets, drains. What can I do about it?
Check to see if your neighbors are having a similar slow drainage problem. Call the City Wastewater Division and we will check the mains. City crews will notify you if the problem is in the City main or not. If the city does not have a problem you will need to call a plumber to clean your lateral.

There is a manhole cover in my neighborhood that rattles every time a vehicle rolls over it. What can I do about it?
Report it by filling out an Action Request Form or by calling 237-3865.

What causes sewer odors inside the house?
Sewage has a natural tendency to produce odors; all sewers have odors. The plumbing system in your home is designed to prevent these odors from entering the house by using a vapor trap. If you are experiencing odors indoors, it is likely that there is a problem with the vapor trap. If you experience a problem with your vapor trap, a plumber can help you.

Atmospheric conditions can also affect odors from sewer systems entering the house. When barometric pressure is falling or is very low, the air outside can be heavier than air from the sewer system, causing pressure to build up in the sewer system. This temporary condition may cause indoor odors, but will resolve as barometric pressure increases.

What is the purpose of vapor traps?
Every water fixture in your house has a vapor trap. This “U” shaped pipe is clearly visible under sinks, and is present in some form on all lines draining to the sewage system. The “U” shape holds water, preventing gases from backing up from the sewer into the house through the sink drain.

What is the purpose of the roof vent?
All houses have plumbing vents (also called a vent stack) that extend through the roof. These vents allow air to flow both in and out of the house plumbing system, helping water to flow through the pipes. Working in combination with the vapor traps, gases from the sewer system are safely vented.

What are some of the problems that can occur?
When sewer gasses are present inside the home, usually one or more vapor traps has dried out. The water in a vapor trap will evaporate if the fixture is not used often; seldom-used bathrooms or utility sinks are commonly odor sources. The simple solution is to periodically run water (one or two cups) into the drain to refill the trap.

What if the odor is outside the house?
If there is a sewer odor outside your home, report it to the City Wastewater Division at 237-3865. Note, however, the City is renown for natural sulfur springs, and these sulfur water sources have a strong odor, often smelling like sewage.

How do I file a claim if I have property damage caused by a sewer back up?
Contact the Office of the City Clerk at 237-3960 or at 1000 Spring Street, 2nd Floor to request a Claim Form. The original and one identical copy of the claim form, together with one copy of all attachments, are to be filed with the Office of the City Clerk. For more information, visit the City Clerk page.

Who maintains the sewer line?
The City maintains all sewer mains, which are located in the street or public utilities easements. Residents and business owner’s own the lateral connections to the mains, laterals typically run on the owners’ property and on streets or public areas to reach the main.

Property owners maintain their sewer lateral line, including the connection to the public sewer main. Locating the lateral is also a property owner’s responsibility, although the City will attempt to assist by providing recorded, available information.

To find out where your sewer lateral is located, you can check with the Engineering Division of the Community Development Department by calling (805) 237-3860.

How do I report a problem?
To report a problem in the sewer main during the hours of 7:00 a.m. to 3:30 p.m., call the Wastewater Treatment Plant at (805) 237-3865. Between the hours of 3:30 p.m. and 7:00 a.m., contact the Police Department at (805) 237-6464.


Wastewater Treatment Plant Annual Report

Salt/Nutrient Management Plan for Paso Robles Groundwater Basin

Recycled Water Master Plan

Local RV Dump Stations

  • Valero Gas Station
    2340 Spring Street

  • Delta RV
    1960 Ramada Drive

You are here:   Home    Government     Departments    Public Works    Wastewater    FAQ