Public water system · CA5601701
ActiveDennison Park
At a glance
Dennison Park (PWSID CA5601701) is an active transient non-community water system in Ventura County, California. It reports serving 102 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 9 violations for this system; 3 are health-based, and the most recent began in January 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
102
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Dennison Park compare with other water systems in Ventura County?
By EPA's size categories, Dennison Park is a very small system (500 people or fewer). Ventura County has 95 active public water systems. Its population served is well below the county average of 9,293 people per system, and accounts for less than 0.1% of the 882,799 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Dennison Park is about 29% below 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. California has 3,016 active transient non-community water systems, 40% of the state's 7,479 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 6,179 California systems (83%) list groundwater as their primary source.
Who owns and regulates Dennison Park?
EPA lists Dennison Park as owned by a local government. The CA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 29 of the 95 active systems in Ventura County (31%) are also owned by a local government.
Does Dennison Park have drinking water violations?
EPA's records list 9 violations for this system; 3 are health-based, and the most recent began in January 2024. The violations listed here began between August 1984 and January 2024. By type: 3 monitoring and reporting, 3 contaminant level above the legal limit, 2 monitoring and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (6 of them). EPA lists 8 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 |
|---|---|---|---|---|
| 2024-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2023-07-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2014-01-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2010-04-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2010-02-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2008-07-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2007-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1984-08-01 | Public notice, recordkeeping or otherNotification, Public · code 06 | Not reported | No | Archived |
All 9 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.
Dennison Park: frequently asked questions
Who runs Dennison Park?
Dennison Park (PWSID CA5601701) is a transient non-community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Dennison Park serve?
Dennison Park reports serving 102 people through 1 service connection in Ventura County, California.
Where does Dennison 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 Dennison Park have any drinking water violations?
EPA's records list 9 violations for this system; 3 are health-based, and the most recent began in January 2024. 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 Dennison 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 9 violations for this system; 3 are health-based, and the most recent began in January 2024. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Dennison Park's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Dennison 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 Ventura County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Oxnard Water Dept | Ventura | 200,232 | Community | Purchased surface water |
| Ventura Water Department | Ventura | 113,500 | Community | Surface water |
| Ventura Wwd No. 8 - Simi Valley | Ventura | 94,738 | Community | Purchased surface water |
| Cal American Water Co | Ventura | 66,809 | Community | Purchased surface water |
| City of Thousand Oaks Water Department | Ventura | 53,157 | Community | Purchased surface water |
| Camarillo Water Dept | Ventura | 46,824 | Community | Purchased surface water |
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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, “Dennison Park, PWSID CA5601701, California”, https://aquacensus.com/water-systems/california/dennison-park-ca5601701 (data as of October 1, 2026).