Marin County Sewer Lateral Inspections: Point of Sale Rules and Repairs

What a private sewer lateral is

Your sewer lateral is the pipe that carries wastewater from the house to the public sewer main, usually out under the street. In Marin County the property owner owns that pipe and pays to maintain it. The sanitary district owns the main. Many laterals here are 50 to 100 years old, made of clay or cast iron. Roots, soil movement, and age crack them. A cracked lateral leaks sewage into the ground and lets rainwater pour into the sewer system, which overloads treatment plants during storms. That is why Marin districts now require proof the pipe is sound when a property changes hands.

Ross Valley Sanitary District point of sale rules

Ross Valley Sanitary District (RVSD) serves Fairfax, San Anselmo, Ross, Kentfield, Kent Woodlands, Greenbrae, Larkspur, Bon Air, Murray Park, Sleepy Hollow, and Oak Manor. Its Private Sewer Lateral Ordinance took effect July 1, 2014, and the property sale requirement took effect January 1, 2015. You need a Certificate of Compliance from RVSD when any of these happen:

• The property sells. The responsible party has 90 days after close of escrow to reach compliance.
• A remodel exceeds $75,000.
• A bathroom is added.

The process runs through a licensed plumbing contractor. We camera the lateral, submit the video and report with a sewer permit application, complete any repairs, and then an RVSD inspector witnesses a pressure test on the line. Pass that test and the inspector issues the Compliance Certificate. RVSD adjusts its permit fees each July 1, so check the district fee schedule for current numbers or ask us. If the lateral needs full replacement, RVSD offers grant and loan programs that can offset the cost.

Sanitary District No. 5: Tiburon and Belvedere

Sanitary District No. 5 of Marin County covers the City of Belvedere and the Town of Tiburon east of Gilmartin Drive. Its lateral rules come from Ordinance 2014-02a, in effect district wide since March 4, 2015. An inspection is required when:

• The property is bought or sold.
• Building or remodel work exceeds $50,000 within a 3 year period.
• The district works on the sewer main near you, or the road above your lateral is resurfaced.

Two exemptions matter for sellers. A lateral installed or replaced within the past 20 years is exempt. So is a lateral inspected within the past 3 years with all required repairs completed. The CCTV report is submitted online through the Forward Lateral portal for district review. If the pipe is free of leaks and defects, the district issues a permit confirming compliance. The posted inspection permit fee was $235 on the October 2024 schedule. Confirm the current amount with the district office at (415) 435-1501.

Mill Valley and the SASM area

The Sewerage Agency of Southern Marin (SASM) treats wastewater for about 29,500 residents in southern Marin. Its board approved a model lateral ordinance and each member agency adopts its own version. Mill Valley requires a lateral inspection when a property sells, when permitted improvements reach $50,000 over a 3 year period, when a permit adds plumbing fixtures, after a sewage overflow, or before the city paves the street above your line. The CCTV video, report, and site sketch go to Mill Valley Public Works with the city review fee, so confirm the current fee with the city before you file. Homes in Tamalpais Valley, Almonte, Alto, and Homestead Valley sit in separate small districts, and rules vary. We can tell you which district a property is in with one phone call.

What the CCTV inspection involves

A technician feeds a camera into the lateral through a cleanout and records the pipe from the house to the main. The video shows root intrusion, cracks, offset joints, sags that hold water, and breaks, each tagged with a distance marker. Most homes take about an hour. If the property has no usable cleanout, we install one first, which districts want anyway. You get the footage plus a written report stating pipe material, length, and every defect.

Pass, fail, and the repair paths

A passing lateral gets certified and you are done. A failing lateral needs work before the district signs off. There are three common repair paths:

• Spot repair. Dig up and replace one bad section. Right call when the rest of the pipe tests sound.
• Cured in place lining. A resin sleeve hardens inside the old pipe. Minimal digging, good for long cracked runs that still hold their grade.
• Full replacement. New pipe by open trench or pipe bursting. The fix for collapsed, back graded, or root choked laterals.

After repairs, the district reinspects or witnesses the pressure test, then issues the certificate.

How CNTRline runs the job, inspection through certificate

We have handled lateral compliance work since 2017 and we know each district and its paperwork. A typical escrow job runs like this:

• First visit: CCTV inspection, with the written report the same week.
• Filing: we submit the video, report, and sewer permit application to the district.
• Repairs: if the lateral fails, we quote every repair path from the same video, then do the work.
• Sign off: the district pressure test or reinspection, then your certificate.

Clean laterals wrap up in days. Full replacements take longer, so in RVSD territory start early in the 90 day window. Call (707) 308-5599 with the property address and we will check the district maps the same day.