Public water system · MA2270001
ActiveMci Shirley
At a glance
Mci Shirley (PWSID MA2270001) is an active community water system in Middlesex County, Massachusetts. It reports serving 3,500 people through 3 service connections. Its primary water source is groundwater, and EPA lists it as owned by a state government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in April 2008.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
3,500
Service connections
3
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Mci Shirley compare with other water systems in Middlesex County?
By EPA's size categories, Mci Shirley is a medium system (3,301 to 10,000 people). Middlesex County has 204 active public water systems. Its population served is about 56% below the county average of 7,986 people per system, and accounts for 0.2% of the 1,629,099 people reported by systems filed under the county. Across Massachusetts, the 1,636 active systems average 6,275 people each. Nationally, the average active community water system reports serving 6,703 people, so Mci Shirley is about half of 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. Massachusetts has 531 active community water systems, 32% of the state's 1,636 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,354 Massachusetts systems (83%) list groundwater as their primary source.
Who owns and regulates Mci Shirley?
EPA lists Mci Shirley as owned by a state government. The MA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 6 of the 204 active systems in Middlesex County (2.9%) are also owned by a state government.
Does Mci Shirley have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in April 2008. The violations listed here began between April 2008 and April 2008. By type: 12 monitoring and reporting. The contaminants or rules involved are Vinyl chloride, Trichloroethylene, Benzene and trans-1,2-Dichloroethylene. EPA lists 12 as resolved. 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 |
|---|---|---|---|---|
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Vinyl chloridecode 2976 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Trichloroethylenecode 2984 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Benzenecode 2990 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | trans-1,2-Dichloroethylenecode 2979 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlorobenzenecode 2989 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Ethylbenzenecode 2992 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloroethanecode 2980 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dichloromethanecode 2964 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1-Dichloroethylenecode 2977 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Xylenes, Totalcode 2955 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Carbon tetrachloridecode 2982 | 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.
Mci Shirley: frequently asked questions
Who runs Mci Shirley?
Mci Shirley (PWSID MA2270001) is a community water system owned by a state government. It is regulated by the MA state drinking water program.
How many people does Mci Shirley serve?
Mci Shirley reports serving 3,500 people through 3 service connections in Middlesex County, Massachusetts.
Where does Mci Shirley 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 Mci Shirley have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in April 2008. 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 Mci Shirley'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, none is health-based, and the most recent began in April 2008. For current results, consult the system's annual water quality report, EPA ECHO, or the MA state drinking water program.
Where can I find Mci Shirley's water quality report?
As a community water system, Mci Shirley 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 Middlesex County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Lowell Regional Water Utility | Middlesex | 120,418 | Community | Surface water |
| Cambridge Water Department | Middlesex | 118,214 | Community | Surface water |
| Newton Water Dept. (MWRA) | Middlesex | 88,931 | Community | Purchased surface water |
| Somerville Water Dept. (MWRA) | Middlesex | 81,045 | Community | Purchased surface water |
| Framingham Water Dept. (MWRA) | Middlesex | 72,362 | Community | Purchased surface water |
| Malden Water Division (MWRA) | Middlesex | 66,263 | 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, “Mci Shirley, PWSID MA2270001, Massachusetts”, https://aquacensus.com/water-systems/massachusetts/mci-shirley-ma2270001 (data as of October 1, 2026).