Public water system · WA5363450
ActiveOlympia City of
At a glance
City of Olympia (PWSID WA5363450) is an active community water system in Thurston County, Washington. It reports serving 126,966 people through 38,115 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
126,966
Service connections
38,115
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does City of Olympia compare with other water systems in Thurston County?
By EPA's size categories, City of Olympia is a very large system (more than 100,000 people). Thurston County has 322 active public water systems, and City of Olympia is the largest of them by population served. Its population served is about 103 times the county average of 1,233 people per system, and accounts for 32% of the 397,060 people reported by systems filed under the county. Across Washington, the 4,705 active systems average 2,172 people each. Nationally, the average active community water system reports serving 6,703 people, so City of Olympia is about 19 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. Washington has 2,392 active community water systems, 51% of the state's 4,705 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 4,370 Washington systems (93%) list groundwater as their primary source.
Who owns and regulates City of Olympia?
EPA lists City of Olympia as owned by a local government. The WA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 73 of the 322 active systems in Thurston County (23%) are also owned by a local government.
Does City of Olympia have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in July 2025. The violations listed here began between January 2007 and July 2025. By type: 10 monitoring and reporting, 1 public notice, recordkeeping or other and 1 required treatment not met. The contaminants or rules involved are Consumer Confidence Rule, Surface Water Treatment Rule, Toluene and 1,1-Dichloroethylene. EPA lists 10 as archived and 2 as resolved. 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. 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 |
|---|---|---|---|---|
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2014-10-01 | Required treatment not metFailure to Filter (SWTR) · code 42 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Toluenecode 2991 | No | Archived |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1-Dichloroethylenecode 2977 | No | Archived |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlorobenzenecode 2989 | No | Archived |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloroethanecode 2980 | No | Archived |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Tetrachloroethylenecode 2987 | No | Archived |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Benzenecode 2990 | No | Archived |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | o-Dichlorobenzenecode 2968 | No | Archived |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Vinyl chloridecode 2976 | No | Archived |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | trans-1,2-Dichloroethylenecode 2979 | No | Archived |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,1-Trichloroethanecode 2981 | No | 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.
City of Olympia: frequently asked questions
Who runs City of Olympia?
City of Olympia (PWSID WA5363450) is a community water system owned by a local government. It is regulated by the WA state drinking water program.
How many people does City of Olympia serve?
City of Olympia reports serving 126,966 people through 38,115 service connections in Thurston County, Washington.
Where does City of Olympia 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 City of Olympia have any drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in July 2025. 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 Olympia'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, one is health-based, and the most recent began in July 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the WA state drinking water program.
Where can I find City of Olympia's water quality report?
As a community water system, City of Olympia 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 Thurston County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Lacey Water Department | Thurston | 105,178 | Community | Groundwater |
| Tumwater City of | Thurston | 51,802 | Community | Groundwater |
| Yelm City of | Thurston | 17,355 | Community | Groundwater |
| Tanglewilde Thompson Place 600 | Thurston | 7,900 | Community | Groundwater |
| Pattison 500 | Thurston | 4,643 | Community | Groundwater |
| Grand Mound | Thurston | 3,764 | Community | Groundwater |
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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, “Olympia City of, PWSID WA5363450, Washington”, https://aquacensus.com/water-systems/washington/olympia-city-of-wa5363450 (data as of October 1, 2026).