Public water system · CA4300575
ActiveTwin Valley Inc.
At a glance
Twin Valley Inc. (PWSID CA4300575) is an active community water system in Santa Clara County, California. It reports serving 317 people through 96 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 12 are health-based, and the most recent began in November 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
317
Service connections
96
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Twin Valley Inc. compare with other water systems in Santa Clara County?
By EPA's size categories, Twin Valley Inc. is a very small system (500 people or fewer). Santa Clara County has 121 active public water systems. Its population served is well below the county average of 17,334 people per system, and accounts for less than 0.1% 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 Twin Valley Inc. is well below 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. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 6,179 California systems (83%) list groundwater as their primary source.
Who owns and regulates Twin Valley Inc.?
EPA lists Twin Valley Inc. as privately owned. 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. 82 of the 121 active systems in Santa Clara County (68%) are also privately owned.
Does Twin Valley Inc. have drinking water violations?
Of the 12 most recent violations in EPA's records, 12 are health-based, and the most recent began in November 2023. The violations listed here began between October 2021 and November 2023. By type: 12 contaminant level above the legal limit. The contaminant or rule involved most often is Nitrate (12 of them). EPA lists 12 as archived. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2023-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2023-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2023-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2022-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2022-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2022-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2022-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2022-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2022-05-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2021-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2021-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2021-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
The 12 most recent 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.
Twin Valley Inc.: frequently asked questions
Who runs Twin Valley Inc.?
Twin Valley Inc. (PWSID CA4300575) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Twin Valley Inc. serve?
Twin Valley Inc. reports serving 317 people through 96 service connections in Santa Clara County, California.
Where does Twin Valley Inc. get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Twin Valley Inc. have any drinking water violations?
Of the 12 most recent violations in EPA's records, 12 are health-based, and the most recent began in November 2023. 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 Twin Valley Inc.'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. Of the 12 most recent violations in EPA's records, 12 are health-based, and the most recent began in November 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Twin Valley Inc.'s water quality report?
As a community water system, Twin Valley Inc. 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 |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Twin Valley Inc., PWSID CA4300575, California”, https://aquacensus.com/water-systems/california/twin-valley-inc-ca4300575 (data as of October 1, 2026).