Frequently Asked Questions About Sewers

Your first inspection is required when trench digging is complete. We must see the bottom of the trench. This is called a trench inspection.

Sewer inspections during the construction phase assure a quality connection. This protects the treatment plant from storm water infiltration. It also protects your property from sewage leaks.

We schedule multiple inspections throughout the county every day. Because Sonoma County is so large, we try to schedule inspections for projects that are located near each other on the same day. With 48 hours notice we are able to inspect much more efficiently.

Although they may seem to be working, older systems are seldom tightly sealed. This can allow storm water to enter the system which will cause problems at the treatment plant.

This type of connection is typically used for joining unlike pipes, such as iron pipe to plastic pipe.

The depth of cover required for plastic pipe is a minimum of 24 inches. This depth helps to protect the pipe from damage. If you are using iron pipe the minimum cover depth is 18 inches.

The purpose of the backflow preventer is to stop sewage from backing up in your home in the event that the main sewer line becomes blocked. Each sewer connection is unique. Your house may be at a slightly lower elevation than that of your neighbor.

This varies from one project to another. You must use #4 rock (pea gravel with fines) or other materials approved by PRMD.

A licensed contractor is required for any work in a public right of way. On private property, we recommend the use of a licensed contractor if the trench depth is over 5' or if a grease trap or monitoring manhole is required.

Sewer/Sanitation District

To find out if your property is within a sewer/sanitation district, use our Parcel Report tool to look up by Assessor's Parcel Number (APN) or street address. It contains important information about your parcel including sanitation district. Look for "Sanitation District" in the search results. If your property is within a sanitation district, the name of the district is displayed. If your property is not within a sanitation district, "Not Applicable" is displayed.

Hooked to Sewer

If you are within a sanitation district, you can confirm if your property is hooked to the sewer by calling us at (707) 565-2268 during regular phone hours and ask to speak with staff in the Sanitation Section. Please have your Assessor's Parcel Number (APN) available. This number can be found on your annual property tax bill or by searching for your street address via the Parcel Report. If you don't have a tax bill available or access to the online link we can locate the property if you provide us with the street address and the owner's name.

First you should determine whether your property is within a sewer district. If your property is not within a sewer district you must obtain an Outside Service Agreement. If your property is within a sewer district there are several factors involved, including;

• If there is a mainline nearby.
• If there is a lateral from this mainline to your property.

A "No" answer to either of these questions triggers the need for a plan check, which could be a simple review of a hand drawn site plan, or a thorough review of engineered plans.

In addition, the following questions must be answered;

Is there a gravity flow to the mainline? If not, you will need a pumping system.

If there is an existing septic tank, it must be destroyed. This requires a Septic Tank Destruction Permit from Permit Sonoma's Well and Septic Section.

Under normal circumstances you will need a sewer permit and an encroachment permit. Fees will be charged per the current fee schedule.

No. Installation is your responsibility.

Who pays for connecting my property to sewer?

A licensed, bonded contractor with current insurance is required for any work in a public right of way. We recommend the use of a licensed contractor if the trench depth is over 5' or if a grease trap or monitoring manhole is required.