Drain Cleaning in Palo Alto, CA

A Homeowner’s Guide to Drain Cleaning in Palo Alto

One drain, or the whole house?

Where the clog is decides who you call. A slow kitchen sink, a tub that holds water or a toilet that won’t flush is a clog in the house plumbing, usually within a few feet of the fixture or in the branch line in the wall. We clear those with hand augers, drum machines and toilet augers sized for the pipe.

When several fixtures back up at once, water rises in a shower or floor drain as a toilet flushes, or sewage appears at the outdoor cleanout, the blockage is in the sewer lateral, the pipe from the house to the City main. In Palo Alto that changes the first step.

Call CPAU before the lateral is cleared

The City of Palo Alto runs both the wastewater mains and the gas system. It has found gas lines that were drilled through sewer laterals during past utility work, called cross bores, and a cutting head run through the sewer can rupture one. CPAU’s safety guidance is direct:

• Call Utilities Dispatch at (650) 329-2579, 24 hours a day, before a blocked home sewer line is cleared or repaired.
• Don’t run a sewer clearing machine on the lateral until the obstruction has been assessed.
• If you smell gas or see bubbles rising in a toilet bowl, leave right away, leave the doors open, and call 911 and City Utilities from a safe distance.

The City’s cross-bore inspections are done by its contractor, Cratus Inc.; Utilities Engineering, (650) 566-4501, can confirm a crew is theirs. Once CPAU has cleared its part of the line or confirmed the blockage is on your side, we clear the rest.

Whose section is it: the City cleanout

CPAU’s Rule 23 splits the lateral at the City Sewer Cleanout, normally a box in the planting strip:

• Reachable City cleanout: CPAU owns and clears the lower lateral, from the main through the cleanout. The upper lateral, from the cleanout to the house, is yours.
• No reachable City cleanout, or yours more than 5 feet behind the property line: the whole lateral is yours.
• Main in a rear-yard easement: the City keeps only the main; your lateral runs all the way to it.

Rule 23 also puts cleanup costs from a backup on the owner when the stoppage was in the owner’s part. Keep the cleanout box visible and reachable: it’s where both CPAU’s crew and ours get into the line. See main drain and sewer cleaning.

Roots, rain and what goes down the drain

Tree roots find their way into older laterals through joints and cracks. We cut them out from inside the pipe with rooter service or scour the line with hydro jetting, then camera-inspect to see where they got in. The City favors mechanical root removal over flushed root killers, and copper-based root killers are banned in the Bay Area.

A few City rules come with every lateral:

• Roof, yard and foundation drainage may not enter the sewer without a permit from the Regional Water Quality Control Plant, so a downspout tied into a cleanout has to come out.
• Construction debris may not go down the sewer (PAMC 16.09.035), which matters during a remodel.
• Fixtures at ground level or below need an approved backwater valve.

Eichlers and older houses

Palo Alto’s Housing Element puts the median home’s build year at 1955, and homes in Professorville date from about 1893 to the 1930s. Lines that old are often cast iron or clay, which crack, scale up inside and let roots in, so a clog that keeps returning is worth a camera look.

Eichler Homes built some 2,700 houses in Palo Alto, and the City’s Eichler guidelines note that their plumbing was placed in the concrete slab, where repairs can mean invasive work. That’s why we confirm with a camera what is actually wrong before suggesting anything beyond cleaning. See drain video inspection.

When cleaning isn’t enough

If the camera shows a break, a sag or a root-filled joint, the fix is a repair rather than another cleaning. Plumbing permits go through the City’s Accela Citizen Access portal, and a sewer repair that is the only work at a single-family home can qualify for the Over-the-Counter Residential MEP Permit Pilot. Digging under a public street tree also needs an Urban Forestry Tree Permit, (650) 496-5953. See sewer line service in Palo Alto and our service area.

Sources

City of Palo Alto Utilities: Utilities Safety: sewer line clearing, cross bores and gas safety · Rule 23, Special Wastewater Utility Regulations (effective June 1, 2026) · Contact Utilities. Public Works: Urban Forestry: Protected Trees · Urban Forestry FAQ · Regional Water Quality Control Plant. Planning and Development Services: Over-the-Counter Residential MEP Permit Pilot Program · Eichler Neighborhood Design Guidelines (2018) · 2023–2031 Housing Element · Professorville Design Guidelines (2016). Checked October and November 2026.