Public water system · WA53SP530
ActiveMillersylvania State Park
At a glance
Millersylvania State Park (PWSID WA53SP530) is an active transient non-community water system in Thurston County, Washington. It reports serving 3,456 people through 72 service connections. Its primary water source is groundwater, and EPA lists it as owned by a state government. EPA's records list 4 violations for this system; none is health-based, and the most recent began in April 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
3,456
Service connections
72
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Millersylvania State Park compare with other water systems in Thurston County?
By EPA's size categories, Millersylvania State Park is a medium system (3,301 to 10,000 people). Thurston County has 322 active public water systems. Its population served is about 180% above the county average of 1,233 people per system, and accounts for 0.9% 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 transient non-community water system reports serving 144 people, so Millersylvania State Park is about 24 times that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. Washington has 1,913 active transient non-community water systems, 41% 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 Millersylvania State Park?
EPA lists Millersylvania State Park as owned by a state 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. 10 of the 322 active systems in Thurston County (3.1%) are also owned by a state government.
Does Millersylvania State Park have drinking water violations?
EPA's records list 4 violations for this system; none is health-based, and the most recent began in April 2025. The violations listed here began between March 1992 and April 2025. By type: 2 monitoring and 2 monitoring and reporting. The contaminant or rule involved most often is Revised Total Coliform Rule (2 of them). EPA lists 3 as resolved and 1 as archived. 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. 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 |
|---|---|---|---|---|
| 2025-04-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2019-04-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2019-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 1992-03-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Archived |
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.
Millersylvania State Park: frequently asked questions
Who runs Millersylvania State Park?
Millersylvania State Park (PWSID WA53SP530) is a transient non-community water system owned by a state government. It is regulated by the WA state drinking water program.
How many people does Millersylvania State Park serve?
Millersylvania State Park reports serving 3,456 people through 72 service connections in Thurston County, Washington.
Where does Millersylvania State Park 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 Millersylvania State Park have any drinking water violations?
EPA's records list 4 violations for this system; none is health-based, and the most recent began in April 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 Millersylvania State Park'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; none is health-based, and the most recent began in April 2025. For current results, consult EPA ECHO, or the WA state drinking water program.
Where can I find Millersylvania State Park's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Millersylvania State Park is a transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Thurston County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Olympia City of | Thurston | 126,966 | Community | Groundwater |
| 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 |
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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, “Millersylvania State Park, PWSID WA53SP530, Washington”, https://aquacensus.com/water-systems/washington/millersylvania-state-park-wa53sp530 (data as of October 1, 2026).