Commercial Plumber in Redwood City, CA

A Property Manager’s Guide to Plumbing in Redwood City

Water and sewer: the City, the County and SVCW

Redwood City Public Works supplies water to more than 24,000 customers in Redwood City and parts of San Carlos, Woodside and unincorporated San Mateo County. Sewer is less uniform: the City provides sewer service within its mapped service area, which includes Redwood Shores, but some Redwood City properties are served by San Mateo County. The agency named on the sewer bill is your provider, and the City’s GIS map shows the City sewer service area. Wastewater from City sewers is treated by Silicon Valley Clean Water (SVCW), a joint powers authority serving Belmont, Redwood City, San Carlos and the West Bay Sanitary District, based at 1400 Radio Road.

Save these numbers with your building’s emergency contacts: Public Works at (650) 780-7464 on weekdays, City dispatch at (650) 780-7190 after hours, and San Mateo County at (650) 363-4100 for County-sewered properties.

Sewer laterals: split at the property-line cleanout

Redwood City divides the lateral in two. The upper lateral, everything on the private side of the property line including the cleanout, is the owner’s to maintain and repair. The lower lateral, from the property line to the main, is maintained by the City. That only works if there is a property-line cleanout within 5 feet of the property line that staff can reach. The City won’t install one: the owner gets a cleanout permit from the Engineering and Construction Division (650-780-7380) and hires a licensed plumber.

For buildings without an accessible cleanout, adding one is the step that brings the lower lateral under City maintenance. Any lateral repair also needs an Engineering permit, and a City engineer inspects the finished work. See commercial sewer repair.

Restaurants: SVCW’s grease program

In Redwood City, San Carlos and unincorporated San Mateo County, SVCW staff visit restaurants and other food service facilities about grease handling. The requirements on SVCW’s posters:

• Grease traps: clean at least every 30 days, or when 25% full of grease and solids.
• Grease interceptors: pump at least every 90 days, or when the final chamber is 25% full, whichever comes first. The pumper should empty the whole interceptor, not decant back into it, and list the disposal site on the invoice.
• Records: keep maintenance records on site for at least 3 years; missing records violate the local sewer ordinance.
• No chemicals, enzymes or bacteria to dissolve grease in a trap or interceptor; dishwashers and garbage grinders must not drain to a grease trap.

Interceptor pumping handles the interceptor; scheduled hydro jetting keeps the kitchen lines and lateral leading to it open. SVCW asks that standpipes be checked after lines are snaked or jetted.

Backflow testing

Redwood City’s Cross Connection Control Ordinance (City Code ch. 38, art. VII) protects the drinking water supply from backflow, and the City requires that all backflow assemblies be tested or inspected every year, along with any wells. The City accepts results only from testers on its Qualified Tester List. Routine tests, repairs and replacements are reported online through the City’s test entry portal, due within 30 days of the City’s first notice; new installations go on the City’s written form within 15 days. A City-issued tag goes on each assembly that passes. We install and repair the assemblies these rules require; see backflow preventers.

Recycled water east of 101 and downtown

The City’s recycled water system serves more than 450 connections, from Redwood Shores and the Bayfront to downtown extensions along Walnut, Marshall and Broadway. Within the recycled water service area, City Code ch. 38, art. VIII requires recycled water for landscaping at existing and remodeled commercial buildings, and both landscaping and separate internal (dual) plumbing in new commercial, institutional and multifamily projects. Approved uses include toilet and urinal flushing, cooling and irrigation; recycled water must never be connected to domestic plumbing.

Permits for commercial plumbing work

The Building Division accepts permit applications online only, through the City’s eTRAKiT portal, which is also used to schedule inspections; general questions go to permits@redwoodcity.org or (650) 780-7350. Sewer lateral repairs and cleanout installations are permitted separately by the Engineering and Construction Division, which also runs street encroachment permits. Contractors need a Redwood City business license before working in the city.

Water heaters and water quality

All of Redwood City’s drinking water comes from the San Francisco Regional Water System (Hetch Hetchy), operated by the SFPUC; the 2025 report notes the City receives no SFPUC groundwater. Hardness ranged from 8.1 to 112 ppm, averaging 62 ppm, so scale is a smaller factor in water heater life than in hard-water areas. The City’s service line inventory, finished in October 2025, found no lead in either the City-owned or customer-owned portions of service lines; the customer owns the line from the meter to the building. For electrification, WestLight Energy (formerly Peninsula Clean Energy) offers commercial and multifamily owners free technical help with replacing gas water heaters and other gas equipment. See commercial water heaters.

Sources

City of Redwood City: Water · Sewer laterals and cleanouts · Sewer FAQ · Sewer overflows · Cross Connection Control Program · For backflow testers · Water quality · 2025 water quality report · Recycled water · Using recycled water · Get a permit. Silicon Valley Clean Water: About SVCW · FOG program · Grease interceptor maintenance · Grease trap maintenance · Chemical prohibitions. WestLight Energy: Electric buildings for businesses. Checked October 2026.