Public Water Partners

PLEASANTON, CA · Alameda County

CASTLEWOOD DOMESTIC WATER SYSTEM Water System

Consumer Confidence Report status

CASTLEWOOD DOMESTIC WATER SYSTEM must publish a Consumer Confidence Report — the annual drinking water quality report covering calendar year 2026 — by July 1, 2027.

As of August 1, 2026, EPA's federal records show no open violations for CASTLEWOOD DOMESTIC WATER SYSTEM.

Data sourced from the EPA ECHO database (SDWA bulk download), last refreshed August 1, 2026. This is a record-keeping and public-information tool — it does not replace California’s official records. Always confirm current status with California before making decisions based on this information.

System facts

System ID (PWSID)
CA0105008
System type
Community Water System
Population served
524
Service connections
207
Ownership
local government
Water source
groundwater (wells)

CASTLEWOOD DOMESTIC WATER SYSTEM is one of 728 community water systems in California in the 501 to 3,300 people size category, serving 524 people from groundwater.

As of August 1, 2026, its federal record holds 2 entries between 1980 and 1981, all of which EPA lists as closed. Nothing has been added since 1981.

All 2 are monitoring and reporting requirements — the category that accounts for about four in five of all violations in EPA's national dataset — rather than findings about the water itself. The record involves the Radionuclides and Revised Rad Rule.

Violation history

  • Monitoring, Regular

    —

    Gross Alpha, Excl. Radon and U

    October 1, 1981 – September 30, 1982

    Archived

  • Monitoring, Regular

    —

    Gross Alpha, Excl. Radon and U

    October 30, 1980 – October 29, 1981

    Archived

Archived closed in EPA's records (typically due to age or a data correction)

Enforcement actions

No enforcement actions on record for this system.

Common questions

Is CASTLEWOOD DOMESTIC WATER SYSTEM required to publish a Consumer Confidence Report?

Yes. CASTLEWOOD DOMESTIC WATER SYSTEM is a community water system, and federal rules (40 CFR 141 Subpart O) require every community water system to publish a Consumer Confidence Report each year.

When is CASTLEWOOD DOMESTIC WATER SYSTEM’s next Consumer Confidence Report due?

CASTLEWOOD DOMESTIC WATER SYSTEM’s next Consumer Confidence Report is due by July 1, 2027. The report covers calendar year 2026.

Does CASTLEWOOD DOMESTIC WATER SYSTEM have any open drinking water violations on record?

As of August 1, 2026, EPA's federal records show no open violations for CASTLEWOOD DOMESTIC WATER SYSTEM.

What is a Consumer Confidence Report?

A Consumer Confidence Report (CCR) is the annual drinking water quality report that community water systems must provide to the people they serve. It lists the contaminants detected in the system’s water during the year, where the water comes from, and how the results compare with federal limits. EPA’s revised CCR rule takes effect January 1, 2027, and the first reports in the new format are due July 1, 2027.

Contact

LINARTE, PHILLIP

510-670-5241

PLEASANTON, CA 94566