Commercial Plumber in Castro Valley, CA

A Property Manager’s Guide to Plumbing in Castro Valley

An unincorporated community: who does what

Castro Valley is not a city. It is an unincorporated community in Alameda County, so the services a city would provide come from separate agencies:

• Water: the East Bay Municipal Utility District (EBMUD).
• Sewer: the Castro Valley Sanitary District (CVSan), which collects wastewater across a service area of about 10 square miles and owns a 25% share of the Castro Valley/Oro Loma treatment plant in San Lorenzo. Oro Loma Sanitary District serves portions of Castro Valley, so confirm which district serves each property; the lateral and grease rules below are CVSan’s.
• Permits: the Alameda County Public Works Agency and other County departments.

Save the emergency numbers with your building’s contacts. Water main breaks and heavy leaks go to EBMUD at 1-866-403-2683, 24/7. Sewer overflows go to CVSan at 510-506-5821; its office line is (510) 537-0757, Monday to Friday, 7 a.m. to 4 p.m. CVSan says sewer main line inspections are part of its free emergency response.

Sewer laterals: CVSan’s inspection at sale

CVSan defines the lateral as the underground pipe from the home or business to its public sewer main, and the property owner maintains, repairs and replaces it. The District Code requires a CVSan repair permit any time a lateral is opened, broken or damaged. CVSan also calls a sewer backflow prevention device, which works like a check valve, the best protection against backups, and floor drains, roof gutters and sump pumps must not be connected to the sanitary sewer.

Castro Valley is not under EBMUD’s regional lateral program. CVSan runs its own Private Sewer Lateral program (Ordinance No. 179), in effect since July 1, 2019. It applies to laterals serving residential, multiple residential, commercial and industrial properties, which must be cleaned and pass a CCTV inspection witnessed by a CVSan inspector:

• before close of escrow on a sale or title transfer;
• when CVSan finds unpermitted lateral work;
• when CVSan finds the lateral is a public nuisance.

Exemptions include a valid certificate, a building constructed 30 years or less before the sale, a full replacement within 30 years, or at least 50% of the lateral replaced within 10 years. Each lateral on a property needs its own inspection permit, and the video is valid for six months. A passing inspection, or a repair of at least half the lateral, earns a certificate for 10 years; a full replacement, 30 years. The PSL page lists $330 for the CCTV inspection permit and $250 for a sewer repair permit. Repairs can be done before or after close of escrow, and CVSan has a time-extension process, so check its current deadline before closing. A camera inspection before listing shows what the District’s inspection is likely to find. See commercial sewer repair.

Restaurants: CVSan’s grease rules

CVSan’s FOG control program requires every food service establishment that produces fats, oils or grease to have a grease trap or interceptor, even if it doesn’t fry, because cleanup still washes grease and food solids into the sewer. The key requirements:

• Cleaning: at least every six months, and often enough that floating grease and settled solids stay below 25% of the hydraulic depth.
• Who cleans: staff may clean small indoor traps; large outdoor interceptors must be cleaned by a licensed grease hauler.
• Records: keep maintenance records for at least three years, and train staff on best practices.
• No enzymes: enzymes, emulsifiers and surfactants may not be used to break up grease in grease devices.
• Inspections: CVSan inspectors may inspect grease handling at any food service establishment in the District.

Restaurant permits and food safety inspections are separate: they come from Alameda County’s food safety program, (510) 567-6700. Between pumpings, scheduled hydro jetting keeps kitchen lines open.

Backflow testing for EBMUD

EBMUD’s cross-connection specialists decide whether a site needs a backflow assembly, for example where the water system connects to a boiler, cooling tower, or booster or recirculating pump, where there is a well, or on fire sprinkler and irrigation systems. When the annual test is due, EBMUD sends the list of authorized testers, and the completed test form must be mailed back within 30 days of the notice. New fire services must have their underground piping flushed before activation, witnessed by EBMUD’s Backflow Section on at least 48 hours’ notice. Questions go to 510-287-0874. We install and repair the assemblies these rules require; see backflow preventers.

Permits from Alameda County

With no city building department, permits for Castro Valley are issued by the Alameda County Public Works Agency’s Building Inspection Department, which permits and inspects privately funded construction in the unincorporated areas. Apply, submit plans, schedule inspections and check permit status through the Alameda County Permit Portal; the Agency is at 399 Elmhurst Street in Hayward, (510) 670-5480. Work in County roads, sidewalks and public rights-of-way needs a County encroachment permit, and lateral work also needs CVSan’s own permit, so allow time for both on sewer projects.

Water heaters: soft water and electrification

EBMUD’s main supply is Mokelumne River water stored in Pardee Reservoir. Its 2025 water quality report lists Castro Valley in the areas served by the Walnut Creek and Orinda treatment plants, which measured 15–21 ppm and 14–40 ppm hardness (about 1–2 grains per gallon); EBMUD notes that an area can be served from a different plant during high demand or maintenance. Scale is usually a smaller concern than in hard-water cities.

Castro Valley is in Ava Community Energy’s service area, and commercial accounts are enrolled in its Bright Choice service by default. Ava’s commercial efficiency program, which offered heat pump water heater incentives, is closed to new enrollments; Ava lists PG&E rebates, BayREN Business and GoGreen Financing for commercial buildings, so check current offers before planning a replacement. See commercial water heaters.

Sources

Castro Valley Sanitary District: Home and contact numbers · Report a sewer emergency · Who we are · Treatment plant · Private Sewer Lateral program · Ordinance No. 179 · FOG control program · Prevent blockages. Oro Loma Sanitary District: About us. EBMUD: Contact and emergencies · Wastewater collection and treatment · Backflow prevention · 2025 water quality report. Alameda County: Building permits, unincorporated areas · Food permits · Encroachment and grading permits · Public Works permits · Public Works Agency. Ava Community Energy: Alameda County · Commercial buildings. Checked October 2026.