Public water system · IL0150200
ActiveMount Carroll
At a glance
Mount Carroll (PWSID IL0150200) is an active community water system in Carroll County, Illinois. It reports serving 1,479 people through 855 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in July 2019.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,479
Service connections
855
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Mount Carroll compare with other water systems in Carroll County?
By EPA's size categories, Mount Carroll is a small system (501 to 3,300 people). Carroll County has 35 active public water systems, and Mount Carroll is the 4th-largest of them by population served. Its population served is about 3.9 times the county average of 384 people per system, and accounts for 11% of the 13,444 people reported by systems filed under the county. Across Illinois, the 3,872 active systems average 3,204 people each. Nationally, the average active community water system reports serving 6,703 people, so Mount Carroll 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. Illinois has 1,773 active community water systems, 46% of the state's 3,872 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,808 Illinois systems (73%) list groundwater as their primary source.
Who owns and regulates Mount Carroll?
EPA lists Mount Carroll as owned by a local government. The IL state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 8 of the 35 active systems in Carroll County (23%) are also owned by a local government.
Does Mount Carroll have drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in July 2019. The violations listed here began between July 2000 and July 2019. By type: 5 monitoring and reporting, 5 contaminant level above the legal limit and 2 public notice, recordkeeping or other. The contaminant or rule involved most often is Combined Radium (-226 and -228) (8 of them). 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 |
|---|---|---|---|---|
| 2019-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Resolved |
| 2005-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2005-01-18 | Public notice, recordkeeping or otherPublic Notification Violation without NPDWR Violation · code 76 | Public Noticecode 7500 | No | Resolved |
| 2005-01-18 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2005-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2004-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2004-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2004-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2000-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
| 2000-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Resolved |
| 2000-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Resolved |
| 2000-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | 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.
Mount Carroll: frequently asked questions
Who runs Mount Carroll?
Mount Carroll (PWSID IL0150200) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Mount Carroll serve?
Mount Carroll reports serving 1,479 people through 855 service connections in Carroll County, Illinois.
Where does Mount Carroll 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 Mount Carroll have any drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in July 2019. 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 Mount Carroll'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, 5 are health-based, and the most recent began in July 2019. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.
Where can I find Mount Carroll's water quality report?
As a community water system, Mount Carroll 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 Carroll County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Savanna | Carroll | 3,020 | Community | Groundwater |
| Thomson Maximum Security Center | Carroll | 2,166 | Community | Purchased groundwater |
| Lanark | Carroll | 1,504 | Community | Groundwater |
| Milledgeville | Carroll | 989 | Community | Groundwater |
| Shannon | Carroll | 801 | Community | Groundwater |
| Thomson | Carroll | 580 | Community | Groundwater |
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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, “Mount Carroll, PWSID IL0150200, Illinois”, https://aquacensus.com/water-systems/illinois/mount-carroll-il0150200 (data as of October 1, 2026).