Backflow Testing Service Areas
Based in San Jose, we provide certified backflow testing across Santa Clara County. Your water provider sets the rules — and it differs city by city. Find your city below to see exactly who you deal with, what's required, and the areas we cover.
Your Water Provider Changes the Whole Process
The backflow testing requirement is universal, but who sends your notice, where your test report gets filed, and how deadlines are enforced all depend on your water provider.
Municipal Utilities
These cities run their own water department, so your notice and filed test report both go through the city itself.
San Jose Water Company
These cities are served by the investor-owned San Jose Water Company, so your notice and filed report route through SJW instead of the city.
Backflow Testing by City
Every city has its own water provider and its own process. Use the block for your city to see who you deal with, what's common locally, and the neighborhoods we cover.
Municipal Utility
City of Santa Clara Water & Sewer Utilities
Backflow Testing in Santa Clara
Santa Clara runs its own cross-connection control program, so both your notice and your filed test report go directly to the city utility — not a third-party provider. That means one point of contact and city-specific deadlines for every property owner.
Property Stock
Santa Clara's older downtown and mid-century neighborhoods carry a lot of legacy double-check and RPZ assemblies that have been in service for decades. Older assemblies are the ones that most often need a repair right at test time, which we usually handle on the same visit.
Common Devices
Irrigation systems, fire sprinkler lines, and commercial RPAs on office, retail, and industrial properties.
Neighborhoods Covered
Municipal Utility
City of Sunnyvale
Backflow Testing in Sunnyvale
Sunnyvale operates its own municipal water department with a city-run cross-connection program. Notices are issued by the city and completed test reports are filed back to the city, so the process stays local end to end.
Property Stock
Sunnyvale is dense with Eichler and other mid-century homes — especially in Birdland, Lakewood Village, and Serra — many of which have irrigation systems and pool fill lines that have never been upgraded. Those older residential assemblies are exactly where we see the most test-time failures.
Common Devices
Residential irrigation lines, pool fill lines, fire sprinkler systems, and commercial RPZs in the downtown and industrial corridors.
Neighborhoods Covered
Municipal Utility
City of Mountain View
Backflow Testing in Mountain View
Mountain View’s water department handles its own cross-connection control program, so compliance notices and filed reports both route through the city. Requirements and deadlines are set locally rather than by an outside water company.
Property Stock
Mountain View mixes older downtown bungalows, mid-century tract homes, and heavy tech-driven redevelopment. Newer office and retail builds almost always carry commercial RPZ assemblies, while older residential lots retain irrigation and pool lines that need annual certification.
Common Devices
Commercial RPZs on new office and retail properties, plus residential irrigation and pool fill lines.
Neighborhoods Covered
Municipal Utility
City of Palo Alto Utilities (CPAU)
Backflow Testing in Palo Alto
Palo Alto is served by its own city utility, CPAU, which enforces a dedicated cross-connection control program. Notices come from the city and test reports are filed back to the city, so there is no private water company involved.
Property Stock
Palo Alto’s high-value older homes tend to have mature landscaping with irrigation systems, pool fill lines, and fire sprinkler systems that have been in place for years. Many of these assemblies are original equipment, which is why annual testing catches wear before it becomes a bigger problem.
Common Devices
Irrigation systems, pool fill lines, residential fire sprinkler lines, and commercial RPAs downtown.
Neighborhoods Covered
Municipal Utility
City of Milpitas
Backflow Testing in Milpitas
Milpitas runs its water utility through the city, with its own cross-connection control program. Notices are issued by the city and completed test reports are returned to the city utility, keeping the whole process local.
Property Stock
Milpitas spans 1960s and 1970s tract homes, newer hillside developments, and a large commercial and industrial base. That mix means we see everything from aging residential double-check assemblies to multi-device RPZ setups on commercial and fire-line systems.
Common Devices
Residential irrigation and double-check assemblies, plus fire-line and RPZ systems across the commercial and industrial corridors.
Neighborhoods Covered
Private Water Company
San Jose Water Company
Backflow Testing in Campbell
Campbell is served by San Jose Water Company, an investor-owned utility, so notices come from SJW rather than the city. Test reports must be filed with San Jose Water’s cross-connection control program, and its deadlines are what drive your schedule.
Property Stock
Campbell blends older downtown bungalows and mid-century homes with commercial centers like The Pruneyard. Residential irrigation lines are the most common device we test, while the commercial corridors carry RPZ assemblies that need annual certification.
Common Devices
Residential irrigation lines, plus commercial RPZ assemblies at downtown and Pruneyard-area properties.
Neighborhoods Covered
Private Water Company
San Jose Water Company
Backflow Testing in Cupertino
Cupertino is served by San Jose Water Company, so your backflow testing notice and your filed test report both run through SJW’s cross-connection control program rather than any city office.
Property Stock
Cupertino’s affluent mid-century homes and newer construction tend to have extensive irrigation systems, pool fill lines, and fire sprinkler lines. Those multi-device residential properties are common here, and testing all devices in a single visit keeps you compliant without repeat trips.
Common Devices
Irrigation systems, pool fill lines, fire sprinkler lines, and commercial fire-line RPZs.
Neighborhoods Covered
Private Water Company
San Jose Water Company
Backflow Testing in Los Gatos
Los Gatos is served by San Jose Water Company, so notices and filed test reports are handled through SJW’s cross-connection control program. Its deadlines set the schedule for every property owner in town.
Property Stock
Los Gatos’ older hillside and tree-lined homes sit on larger lots with substantial irrigation systems, and many have pool fill lines and fire sprinkler systems. The downtown commercial core also carries RPZ assemblies that require annual testing.
Common Devices
Large-lot irrigation systems, pool fill lines, fire sprinkler systems, and downtown commercial RPZ assemblies.
Neighborhoods Covered
Private Water Company
San Jose Water Company
Backflow Testing in Saratoga
Saratoga is served by San Jose Water Company, so your notice and filed report both route through SJW’s cross-connection control program rather than a city department.
Property Stock
Saratoga’s large lots and estate properties feature heavy landscaping with irrigation systems, pool fill lines, and fire sprinkler systems. These properties often carry multiple backflow devices, so we bundle testing into one visit to keep certification current across the whole property.
Common Devices
Irrigation systems, pool fill lines, fire sprinkler lines, and estate-scale multi-device setups.
Neighborhoods Covered
Private Water Company
San Jose Water & San José Municipal Water
Backflow Testing in San Jose
San Jose is served by two different water systems. Most addresses fall under San Jose Water Company, an investor-owned utility, while a separate service area is handled by San José Municipal Water (Muni Water). Both require annual backflow testing, but your notice and filed report go to whichever agency serves your parcel.
Property Stock
San Jose is the largest city in Northern California, spanning century-old downtown blocks, established residential neighborhoods, and new high-rise and industrial development. That range means we test aging residential irrigation assemblies alongside complex multi-device RPZ setups on commercial and fire-line systems.
Common Devices
Residential irrigation and double-check assemblies, commercial RPZs, and fire-line devices across a wide mix of property types.
Neighborhoods Covered
Municipal Utility
City of Gilroy
Backflow Testing in Gilroy
Gilroy operates its own municipal water system with a city-run cross-connection control program. Notices are issued by the city and completed test reports are filed back to the city utility rather than an outside company.
Property Stock
Gilroy blends historic downtown homes, newer residential subdivisions, and a sizable agricultural and food-processing base. That mix brings both residential irrigation devices and larger commercial assemblies tied to industrial water use.
Common Devices
Residential irrigation lines plus commercial and industrial RPZ assemblies.
Neighborhoods Covered
Municipal Utility
City of Morgan Hill
Backflow Testing in Morgan Hill
Morgan Hill runs its water utility through the city, including a cross-connection control program. Notices and filed test reports are handled by the city rather than a private water company.
Property Stock
Morgan Hill’s larger lots, rural edges, and newer subdivisions mean plenty of irrigation systems and pool fill lines, along with commercial and industrial properties closer to the Highway 101 corridor.
Common Devices
Large-lot irrigation systems, pool fill lines, and commercial RPZ assemblies.
Neighborhoods Covered
Private Water Company
California Water Service (Cal Water)
Backflow Testing in Los Altos
Los Altos is served by California Water Service (Cal Water), an investor-owned utility. Backflow notices and filed test reports run through Cal Water’s cross-connection control program.
Property Stock
Los Altos is made up largely of older, high-value homes on tree-lined lots with mature landscaping, so irrigation systems, pool fill lines, and fire sprinkler lines are the devices we certify most often here.
Common Devices
Irrigation systems, pool fill lines, fire sprinkler lines, and commercial RPAs in the village and shopping districts.
Neighborhoods Covered
Private Water Company
California Water Service (Cal Water)
Backflow Testing in Los Altos Hills
Los Altos Hills is served primarily by California Water Service (Cal Water), with portions of the area served by the Purissima Hills Water District. Testing requirements are enforced through the agency that serves your parcel.
Property Stock
Los Altos Hills is defined by large estate lots and extensive landscaping, so many properties carry multiple irrigation devices, pool fill lines, and fire sprinkler assemblies that all need annual testing.
Common Devices
Estate-scale irrigation systems, pool fill lines, and residential fire sprinkler lines.
Neighborhoods Covered
Private Water Company
San Jose Water Company
Backflow Testing in Monte Sereno
Monte Sereno is served by San Jose Water Company, so notices and filed test reports are handled through SJW’s cross-connection control program rather than a city department.
Property Stock
Monte Sereno is a small, quiet residential city of large wooded lots, so irrigation systems, pool fill lines, and residential fire sprinkler lines are the devices we most often test here.
Common Devices
Irrigation systems, pool fill lines, and residential fire sprinkler lines.
Neighborhoods Covered
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