Olympia, WA · Thurston County

TAMOSHAN Water System

Current status

No open violations on record as of July 4, 2026.

This system's next federally required Consumer Confidence Report is due July 1, 2027, under the EPA's revised reporting rule.

Data sourced from the EPA ECHO database (SDWA bulk download), last refreshed July 4, 2026. This is a record-keeping and public-information tool — it does not replace Washington’s official records. Always confirm current status with Washington before making decisions based on this information.

System facts

System ID (PWSID): WA5387140
System type: Community Water System
Population served: 260
Service connections: 94
Ownership: local government
Water source: groundwater (wells)

Violation history

Monitoring, Routine (RTCR)
—
Revised Total Coliform Rule
June 1, 2025 – June 30, 2025
Resolved
Maximum Contaminant Level Violation, Average
Health-based
Total Haloacetic Acids (HAA5)
April 1, 2023 – June 30, 2023
Resolved
Maximum Contaminant Level Violation, Average
Health-based
Total Haloacetic Acids (HAA5)
January 1, 2023 – March 31, 2023
Resolved
Maximum Contaminant Level Violation, Average
Health-based
Total Haloacetic Acids (HAA5)
October 1, 2022 – December 31, 2022
Resolved
Maximum Contaminant Level Violation, Average
Health-based
Total Haloacetic Acids (HAA5)
July 1, 2022 – September 30, 2022
Resolved
Maximum Contaminant Level Violation, Average
Health-based
Total Haloacetic Acids (HAA5)
April 1, 2022 – June 30, 2022
Resolved
Maximum Contaminant Level Violation, Average
Health-based
Total Haloacetic Acids (HAA5)
January 1, 2022 – March 31, 2022
Resolved
Monitoring, Routine (RTCR)
—
Revised Total Coliform Rule
December 1, 2021 – December 31, 2021
Resolved
Monitoring, Routine (RTCR)
—
Revised Total Coliform Rule
November 1, 2021 – November 30, 2021
Resolved
Maximum Contaminant Level Violation, Average
Health-based
Total Haloacetic Acids (HAA5)
October 1, 2021 – December 31, 2021
Resolved
Maximum Contaminant Level Violation, Average
Health-based
Total Haloacetic Acids (HAA5)
July 1, 2021 – September 30, 2021
Resolved
Monitoring and Reporting (DBP)
—
TTHM
October 1, 2018 – December 31, 2018
Resolved
Monitoring and Reporting (DBP)
—
Total Haloacetic Acids (HAA5)
October 1, 2018 – December 31, 2018
Resolved
Maximum Contaminant Level Violation, Average
Health-based
TTHM
April 1, 2017 – June 30, 2017
Resolved
Consumer Confidence Report Complete Failure to Report
—
Consumer Confidence Rule
July 1, 2015 – August 28, 2015
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
June 1, 1999 – June 30, 1999
Archived
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
September 1, 1993 – September 30, 1993
Archived
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
December 1, 1992 – December 31, 1992
Archived
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
October 1, 1992 – October 31, 1992
Archived
Maximum Contaminant Level Violation, Average
Health-based
Cadmium
December 1, 1982 – September 30, 1983
Archived
Monitoring, Regular
—
Gross Alpha, Excl. Radon and U
October 1, 1979 – October 31, 1979
Archived

Resolved addressed and confirmed by the stateArchived closed in EPA's records (typically due to age or a data correction)

Period	Violation	Contaminant / rule	Health-based	Status
June 1, 2025 – June 30, 2025	Monitoring, Routine (RTCR)	Revised Total Coliform Rule	—	Resolved
April 1, 2023 – June 30, 2023	Maximum Contaminant Level Violation, Average	Total Haloacetic Acids (HAA5)	Health-based	Resolved
January 1, 2023 – March 31, 2023	Maximum Contaminant Level Violation, Average	Total Haloacetic Acids (HAA5)	Health-based	Resolved
October 1, 2022 – December 31, 2022	Maximum Contaminant Level Violation, Average	Total Haloacetic Acids (HAA5)	Health-based	Resolved
July 1, 2022 – September 30, 2022	Maximum Contaminant Level Violation, Average	Total Haloacetic Acids (HAA5)	Health-based	Resolved
April 1, 2022 – June 30, 2022	Maximum Contaminant Level Violation, Average	Total Haloacetic Acids (HAA5)	Health-based	Resolved
January 1, 2022 – March 31, 2022	Maximum Contaminant Level Violation, Average	Total Haloacetic Acids (HAA5)	Health-based	Resolved
December 1, 2021 – December 31, 2021	Monitoring, Routine (RTCR)	Revised Total Coliform Rule	—	Resolved
November 1, 2021 – November 30, 2021	Monitoring, Routine (RTCR)	Revised Total Coliform Rule	—	Resolved
October 1, 2021 – December 31, 2021	Maximum Contaminant Level Violation, Average	Total Haloacetic Acids (HAA5)	Health-based	Resolved
July 1, 2021 – September 30, 2021	Maximum Contaminant Level Violation, Average	Total Haloacetic Acids (HAA5)	Health-based	Resolved
October 1, 2018 – December 31, 2018	Monitoring and Reporting (DBP)	TTHM	—	Resolved
October 1, 2018 – December 31, 2018	Monitoring and Reporting (DBP)	Total Haloacetic Acids (HAA5)	—	Resolved
April 1, 2017 – June 30, 2017	Maximum Contaminant Level Violation, Average	TTHM	Health-based	Resolved
July 1, 2015 – August 28, 2015	Consumer Confidence Report Complete Failure to Report	Consumer Confidence Rule	—	Resolved
June 1, 1999 – June 30, 1999	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Archived
September 1, 1993 – September 30, 1993	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Archived
December 1, 1992 – December 31, 1992	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Archived
October 1, 1992 – October 31, 1992	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Archived
December 1, 1982 – September 30, 1983	Maximum Contaminant Level Violation, Average	Cadmium	Health-based	Archived
October 1, 1979 – October 31, 1979	Monitoring, Regular	Gross Alpha, Excl. Radon and U	—	Archived

Resolved addressed and confirmed by the stateArchived closed in EPA's records (typically due to age or a data correction)

Enforcement actions

July 14, 2025State Compliance achieved1 linked violation
September 19, 2023State Compliance achieved8 linked violations
January 20, 2022State Compliance achieved2 linked violations
May 9, 2019State Compliance achieved1 linked violation
May 9, 2019State Compliance achieved1 linked violation
June 30, 2017State Compliance achieved1 linked violation
March 31, 2017State Compliance achieved1 linked violation
September 29, 2016State Compliance achieved1 linked violation
August 28, 2015State Compliance achieved1 linked violation
December 31, 1992State Violation/Reminder Notice1 linked violation
November 30, 1992State Violation/Reminder Notice1 linked violation
October 31, 1992State Violation/Reminder Notice1 linked violation

Contact

TAMOSHAN

Phone not on record

Olympia, WA 98512