Public water system · IL1310050

Active

Aledo

At a glance

Aledo (PWSID IL1310050) is an active community water system in Mercer County, Illinois. It reports serving 3,470 people through 1,820 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 11 violations for this system; 6 are health-based, and the most recent began in September 2020.

Dataset updated October 2026 . Source: EPA SDWIS/ECHO public records.

Population served

3,470

Service connections

1,820

Primary source

Groundwater

System type

CWS

Community water system

System record

PWSIDIL1310050

System typeCommunity water system

Activity statusActive

Population served3,470

Service connections1,820

Primary water sourceGroundwater

Owner typeLocal government

Primacy agencyIL state drinking water program

City servedAledo

StateIllinois

ZIP—

CountyMercer County

How does Aledo compare with other water systems in Mercer County?

By EPA's size categories, Aledo is a medium system (3,301 to 10,000 people). Mercer County has 27 active public water systems, and Aledo is the largest of them by population served. Its population served is about 8.1 times the county average of 426 people per system, and accounts for 30% of the 11,499 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 Aledo 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. 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 Aledo?

EPA lists Aledo 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. 10 of the 27 active systems in Mercer County (37%) are also owned by a local government.

Does Aledo have drinking water violations?

EPA's records list 11 violations for this system; 6 are health-based, and the most recent began in September 2020. The violations listed here began between June 1977 and September 2020. By type: 6 contaminant level above the legal limit and 5 monitoring and reporting. The contaminant or rule involved most often is Gross alpha (excluding radon and uranium) (5 of them). EPA lists 10 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
2020-09-01	Monitoring and reportingMonitoring and Reporting (DBP) · code 27	Haloacetic acids (HAA5)code 2456	No	Resolved
2020-09-01	Monitoring and reportingMonitoring and Reporting (DBP) · code 27	Total trihalomethanes (TTHM)code 2950	No	Resolved
2002-01-01	Monitoring and reportingMonitoring, Regular · code 03	Combined Radium (-226 and -228)code 4010	No	Resolved
2002-01-01	Monitoring and reportingMonitoring, Regular · code 03	Gross alpha (excluding radon and uranium)code 4000	No	Resolved
2000-09-26	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Gross alpha (excluding radon and uranium)code 4000	Yes	Resolved
1999-01-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Combined Radium (-226 and -228)code 4010	Yes	Resolved
1998-06-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Gross alpha (excluding radon and uranium)code 4000	Yes	Resolved
1995-01-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Combined Radium (-226 and -228)code 4010	Yes	Resolved
1994-06-16	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Gross alpha (excluding radon and uranium)code 4000	Yes	Resolved
1991-08-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02	Combined Radium (-226 and -228)code 4010	Yes	Resolved
1977-06-30	Monitoring and reportingMonitoring, Regular · code 03	Gross alpha (excluding radon and uranium)code 4000	No	Archived

All 11 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.

Aledo: frequently asked questions

Who runs Aledo?

Aledo (PWSID IL1310050) is a community water system owned by a local government. It is regulated by the IL state drinking water program.

How many people does Aledo serve?

Aledo reports serving 3,470 people through 1,820 service connections in Mercer County, Illinois.

Where does Aledo 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 Aledo have any drinking water violations?

EPA's records list 11 violations for this system; 6 are health-based, and the most recent began in September 2020. 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 Aledo'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 11 violations for this system; 6 are health-based, and the most recent began in September 2020. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.

Where can I find Aledo's water quality report?

As a community water system, Aledo 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 Mercer County

Water system	County	Population served	Type	Source
Viola	Mercer	970	Community	Groundwater
Sherrard	Mercer	785	Community	Groundwater
Fyre Lake Water Company	Mercer	760	Community	Groundwater
Keithsburg	Mercer	747	Community	Groundwater
New Windsor	Mercer	740	Community	Groundwater
Matherville	Mercer	651	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, “Aledo, PWSID IL1310050, Illinois”, https://aquacensus.com/water-systems/illinois/aledo-il1310050 (data as of October 1, 2026).