Public water system · WA53SP940
ActiveTwanoh State Park
Transient non-community water system in Mason County, Washington, drawing primarily on groundwater.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
3,173
Service connections
49
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
Violations & enforcement
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2019-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2013-12-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2011-03-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2006-12-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 2006-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 2005-11-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 2005-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 2004-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2003-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 2003-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 2003-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | 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.
Twanoh State Park: frequently asked questions
Is Twanoh State Park's water safe to drink?
Twanoh State Park is an active transient non-community water system regulated under the Safe Drinking Water Act, overseen by the WA state drinking water program. EPA's SDWA data records violations for this system — the most recent are listed on this page, including health-based violations; consult EPA ECHO or your annual Consumer Confidence Report for its current compliance status.
Who runs Twanoh State Park?
Twanoh State Park (PWSID WA53SP940) is a state government-owned transient non-community water system, regulated by the WA state drinking water program.
How many people does Twanoh State Park serve?
Twanoh State Park reports serving 3,173 people through 49 service connections in Mason County, Washington.
Where does Twanoh State Park get its water?
EPA SDWIS lists this system's primary water source as groundwater.
Other water systems in Mason County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Shelton City of | Mason | 15,089 | Community | Groundwater |
| Belfair Water District 1 | Mason | 4,432 | Community | Groundwater |
| Lake Cushman System 5 | Mason | 3,675 | Community | Groundwater |
| Belfair State Park | Mason | 2,411 | Transient non-community | Groundwater |
| Timberlake Community Club Inc. | Mason | 2,337 | Community | Groundwater |
| Washington Corrections Center | Mason | 2,223 | Community | Groundwater |
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