Public water system · PA1150157
ActiveWarwick Water Works
At a glance
Warwick Water Works (PWSID PA1150157) is an active community water system in Chester County, Pennsylvania. It reports serving 98 people through 46 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in November 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
98
Service connections
46
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Warwick Water Works compare with other water systems in Chester County?
By EPA's size categories, Warwick Water Works is a very small system (500 people or fewer). Chester County has 254 active public water systems. Its population served is well below the county average of 1,167 people per system, and accounts for less than 0.1% of the 296,348 people reported by systems filed under the county. Across Pennsylvania, the 7,217 active systems average 1,741 people each. Nationally, the average active community water system reports serving 6,703 people, so Warwick Water Works is well below 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. Pennsylvania has 1,762 active community water systems, 24% of the state's 7,217 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 6,632 Pennsylvania systems (92%) list groundwater as their primary source.
Who owns and regulates Warwick Water Works?
EPA lists Warwick Water Works as privately owned. The PA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 173 of the 254 active systems in Chester County (68%) are also privately owned.
Does Warwick Water Works have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in November 2025. The violations listed here began between November 2019 and November 2025. By type: 6 monitoring and reporting, 4 public notice, recordkeeping or other, 1 required treatment not met and 1 reporting. The contaminant or rule involved most often is Groundwater Rule (5 of them). EPA lists 11 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 |
|---|---|---|---|---|
| 2025-11-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Archived |
| 2025-05-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2024-12-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2024-09-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2024-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nickelcode 1036 | No | Resolved |
| 2023-05-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2020-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2019-12-17 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2019-12-16 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2019-11-19 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2019-11-06 | Required treatment not metTreatment Technique, Level 2 Assessment (RTCR) · code 2B | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2019-11-06 | ReportingNotify Level 1/Level 2 Treatment Technique Violation, Correct Action (RTCR) · code 4F | Revised Total Coliform Rulecode 8000 | No | Resolved |
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.
Warwick Water Works: frequently asked questions
Who runs Warwick Water Works?
Warwick Water Works (PWSID PA1150157) is a community water system privately owned. It is regulated by the PA state drinking water program.
How many people does Warwick Water Works serve?
Warwick Water Works reports serving 98 people through 46 service connections in Chester County, Pennsylvania.
Where does Warwick Water Works 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 Warwick Water Works 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 November 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 Warwick Water Works' 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 November 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the PA state drinking water program.
Where can I find Warwick Water Works' water quality report?
As a community water system, Warwick Water Works 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 Chester County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Pa American Royersford | Chester | 49,508 | Community | Surface water |
| Aqua Pa West Chester | Chester | 48,600 | Community | Surface water |
| Pa American Coatesville | Chester | 36,960 | Community | Surface water |
| Aqua Pa Uwchlan | Chester | 35,518 | Community | Purchased surface water |
| Phoenixville Water Dept | Chester | 16,599 | Community | Surface water |
| Downingtown Water Authority | Chester | 9,900 | Community | 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, “Warwick Water Works, PWSID PA1150157, Pennsylvania”, https://aquacensus.com/water-systems/pennsylvania/warwick-water-works-pa1150157 (data as of October 1, 2026).