Skip to content
AquaCensus

Public water system · CT0780051

Active

Knollwood Apartments

At a glance

Knollwood Apartments (PWSID CT0780051) is an active community water system in Tolland County, Connecticut. It reports serving 312 people through 113 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, 2 are health-based, and the most recent began in October 2024.

Dataset updated . Source: EPA SDWIS/ECHO public records.

Population served

312

Service connections

113

Primary source

GW

Groundwater

System type

CWS

Community water system

System record

PWSIDCT0780051
System typeCommunity water system
Activity statusActive
Population served312
Service connections113
Primary water sourceGroundwater
Owner typePrivate
Primacy agencyCT state drinking water program
City servedMansfield
StateConnecticut
ZIP—
CountyTolland County

How does Knollwood Apartments compare with other water systems in Tolland County?

By EPA's size categories, Knollwood Apartments is a very small system (500 people or fewer). Tolland County has 296 active public water systems. Its population served is about 54% above the county average of 202 people per system, and accounts for 0.5% of the 59,796 people reported by systems filed under the county. Across Connecticut, the 2,363 active systems average 1,247 people each. Nationally, the average active community water system reports serving 6,703 people, so Knollwood Apartments 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. Connecticut has 481 active community water systems, 20% of the state's 2,363 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,263 Connecticut systems (96%) list groundwater as their primary source.

Who owns and regulates Knollwood Apartments?

EPA lists Knollwood Apartments as privately owned. The CT state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 253 of the 296 active systems in Tolland County (85%) are also privately owned.

Does Knollwood Apartments have drinking water violations?

Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in October 2024. The violations listed here began between March 2020 and October 2024. By type: 5 monitoring and reporting, 3 public notice, recordkeeping or other, 2 required treatment not met, 1 reporting and 1 monitoring. The contaminant or rule involved most often is Lead and Copper Rule (6 of them). EPA lists 10 as resolved and 2 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.

BeganViolationContaminant or ruleHealth-basedStatus
2024-10-17ReportingLSL Reporting · code 4GLead and Copper Rule Revisionscode 5200NoUnaddressed
2024-10-17Required treatment not metLSL Inventory · code 2ELead and Copper Rule Revisionscode 5200YesUnaddressed
2022-09-29Monitoring and reportingLead Consumer Notice · code 66Lead and Copper Rulecode 5000NoResolved
2022-08-10Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72Consumer Confidence Rulecode 7000NoResolved
2022-07-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2022-07-01Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71Consumer Confidence Rulecode 7000NoResolved
2021-09-29Monitoring and reportingLead Consumer Notice · code 66Lead and Copper Rulecode 5000NoResolved
2021-04-01Monitoring and reportingLead Consumer Notice · code 66Lead and Copper Rulecode 5000NoResolved
2020-09-29Monitoring and reportingLead Consumer Notice · code 66Lead and Copper Rulecode 5000NoResolved
2020-08-15Required treatment not metOCCT/SOWT Treatment Installation/Demonstration · code 58Lead and Copper Rulecode 5000YesResolved
2020-07-01Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71Consumer Confidence Rulecode 7000NoResolved
2020-03-31Monitoring and reportingLead Consumer Notice · code 66Lead and Copper Rulecode 5000NoResolved

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.

Knollwood Apartments: frequently asked questions

Who runs Knollwood Apartments?

Knollwood Apartments (PWSID CT0780051) is a community water system privately owned. It is regulated by the CT state drinking water program.

How many people does Knollwood Apartments serve?

Knollwood Apartments reports serving 312 people through 113 service connections in Tolland County, Connecticut.

Where does Knollwood Apartments 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 Knollwood Apartments have any drinking water violations?

Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in October 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 Knollwood Apartments' 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, 2 are health-based, and the most recent began in October 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the CT state drinking water program.

Where can I find Knollwood Apartments' water quality report?

As a community water system, Knollwood Apartments 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 Tolland County

Water systemCountyPopulation servedTypeSource
University of Connecticut - Main CampusTolland27,199CommunityPurchased surface water
Ctwc - Hebron Center DivisionTolland1,927CommunityGroundwater
Coventry High & Nathan Hale SchoolsTolland1,252Non-transient non-communityGroundwater
Tolland Water DepartmentTolland1,251CommunityGroundwater
Ctwc - Amston Lake DivisionTolland910CommunityGroundwater
Horace Porter SchoolTolland797Non-transient non-communityGroundwater

Related pages

Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.

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, “Knollwood Apartments, PWSID CT0780051, Connecticut”, https://aquacensus.com/water-systems/connecticut/knollwood-apartments-ct0780051 (data as of October 1, 2026).