Public water system · CA4310019
ActiveCity of San Jose - Nsj/Alviso
At a glance
City of San Jose - Nsj/Alviso (PWSID CA4310019) is an active community water system in Santa Clara County, California. It reports serving 45,559 people through 2,206 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's records list 4 violations for this system; 3 are health-based, and the most recent began in April 2008.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
45,559
Service connections
2,206
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does City of San Jose - Nsj/Alviso compare with other water systems in Santa Clara County?
By EPA's size categories, City of San Jose - Nsj/Alviso is a large system (10,001 to 100,000 people). Santa Clara County has 121 active public water systems. Its population served is about 163% above the county average of 17,334 people per system, and accounts for 2.2% of the 2,097,447 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active community water system reports serving 6,703 people, so City of San Jose - Nsj/Alviso is about 6.8 times that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. California has 2,997 active community water systems, 40% of the state's 7,479 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 506 California systems (6.8%) list purchased surface water as their primary source.
Who owns and regulates City of San Jose - Nsj/Alviso?
EPA lists City of San Jose - Nsj/Alviso as owned by a local government. The CA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 34 of the 121 active systems in Santa Clara County (28%) are also owned by a local government.
Does City of San Jose - Nsj/Alviso have drinking water violations?
EPA's records list 4 violations for this system; 3 are health-based, and the most recent began in April 2008. The violations listed here began between April 1992 and April 2008. By type: 2 required treatment not met, 1 contaminant level above the legal limit and 1 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (2 of them). EPA lists 4 as resolved. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2008-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2005-12-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1995-03-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 1992-04-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
All 4 violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
City of San Jose - Nsj/Alviso: frequently asked questions
Who runs City of San Jose - Nsj/Alviso?
City of San Jose - Nsj/Alviso (PWSID CA4310019) is a community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does City of San Jose - Nsj/Alviso serve?
City of San Jose - Nsj/Alviso reports serving 45,559 people through 2,206 service connections in Santa Clara County, California.
Where does City of San Jose - Nsj/Alviso get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does City of San Jose - Nsj/Alviso have any drinking water violations?
EPA's records list 4 violations for this system; 3 are health-based, and the most recent began in April 2008. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is City of San Jose - Nsj/Alviso's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. EPA's records list 4 violations for this system; 3 are health-based, and the most recent began in April 2008. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find City of San Jose - Nsj/Alviso's water quality report?
As a community water system, City of San Jose - Nsj/Alviso must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Santa Clara County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| San Jose Water | Santa Clara | 1,039,920 | Community | Surface water |
| City of Sunnyvale | Santa Clara | 157,566 | Community | Purchased surface water |
| City of Santa Clara | Santa Clara | 130,746 | Community | Purchased surface water |
| Great Oaks Wc Inc. | Santa Clara | 110,088 | Community | Groundwater |
| City of San Jose - Evg/Edv/Coy | Santa Clara | 101,265 | Community | Purchased surface water |
| City of Milpitas | Santa Clara | 81,773 | Community | Purchased surface water |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “City of San Jose - Nsj/Alviso, PWSID CA4310019, California”, https://aquacensus.com/water-systems/california/city-of-san-jose-nsj-alviso-ca4310019 (data as of October 1, 2026).