If you have a problem with your sewer, and you are within Castro Valley Sanitary District’s service area, CALL US FIRST at 510-537-0757. We will inspect our sewer main lines at no charge to you. If it is then determined that the problem is not in the main sewer line, you may wish to call a plumber to check your private sewer lateral (the pipe from your building or home to the main) for a blockage.

If you call a plumber before calling CVSan to check our main sewer line, you will be responsible for all charges incurred by the plumber.

What causes sewer blockages?
Some of the most common causes of sewer blockages are: grease, debris or foreign objects in your sewer lateral or our sewer main lines, partial or complete blockage caused by tree root intrusion into sewer lines, and sewer line collapse caused by old or deteriorated pipes or debris entering the sewer system from illegal connections.

CVSan Main Office: 510-537-0757 (M-F 7:00 a.m. - 4:00 p.m.)

Sewer Emergencies After Hours, please call 510-506-5821.
If you have additional questions, please do not hesitate to call the Main Office.

Here are a few tips that will help protect against blockages:
Sewer main line inspections are part of our free emergency response. Helping reduce blockages can reduce the cost to fix the problem, and reduce overall sewer expenditures.

Backflow Prevention: The best way to protect your home or business from a sewer backup is by installing and maintaining a backflow prevention system. A backflow prevention system acts as a check valve that allows sewage to flow out while blocking any sewage from flowing back into the building. In the event of a sewer or lateral backup the water flowing back towards the building will be released through the backflow instead of surcharging into the building. 

Roots: Don’t plant trees or large shrubs near sewer lines. Roots grow toward breaks and cracks in the pipes in search of a source of water. If roots get inside the pipe, they form blockages.

Grease: Dispose of grease and fats in the green organics cart – don’t put them down the drain! Grease collects and hardens inside the pipes and forms a solid plug that can lead to sewer problems.

Deteriorated pipes: Some homes may have damaged or deteriorated pipes. Before considering upgrades or replacement, you may want to contact a plumber to discuss which options are appropriate for your situation.

Illegal plumbing connections: Don’t connect floor drains, roof gutters, sump pumps, and other drainage systems to the sanitary sewer. It’s illegal and debris and silt will clog your line. Consult a plumber to disconnect illegal connections immediately.