Public water system · IL0370051
ActiveCortland
At a glance
Cortland (PWSID IL0370051) is an active community water system in DeKalb County, Illinois. It reports serving 4,398 people through 1,529 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, 9 are health-based, and the most recent began in July 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
4,398
Service connections
1,529
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Cortland compare with other water systems in DeKalb County?
By EPA's size categories, Cortland is a medium system (3,301 to 10,000 people). DeKalb County has 43 active public water systems, and Cortland is the 6th-largest of them by population served. Its population served is about twice the county average of 2,220 people per system, and accounts for 4.6% of the 95,450 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 Cortland is about 34% 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 Cortland?
EPA lists Cortland 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. 13 of the 43 active systems in DeKalb County (30%) are also owned by a local government.
Does Cortland have drinking water violations?
Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in July 2023. The violations listed here began between January 2005 and July 2023. By type: 9 contaminant level above the legal limit, 2 monitoring and reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Combined Radium (-226 and -228) (10 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 |
|---|---|---|---|---|
| 2023-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2017-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Uraniumcode 4006 | No | Resolved |
| 2008-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Resolved |
| 2007-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2006-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2006-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2006-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2006-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2005-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2005-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | 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 |
| 2005-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | 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.
Cortland: frequently asked questions
Who runs Cortland?
Cortland (PWSID IL0370051) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Cortland serve?
Cortland reports serving 4,398 people through 1,529 service connections in DeKalb County, Illinois.
Where does Cortland 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 Cortland have any drinking water violations?
Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in July 2023. 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 Cortland'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, 9 are health-based, and the most recent began in July 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.
Where can I find Cortland's water quality report?
As a community water system, Cortland 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 DeKalb County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Dekalb | DeKalb | 40,290 | Community | Groundwater |
| Sycamore | DeKalb | 18,500 | Community | Groundwater |
| Sandwich | DeKalb | 7,156 | Community | Groundwater |
| Northern Illinois University-Dekalb | DeKalb | 6,500 | Community | Purchased groundwater |
| Genoa | DeKalb | 5,298 | Community | Groundwater |
| Hinckley | DeKalb | 2,006 | 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, “Cortland, PWSID IL0370051, Illinois”, https://aquacensus.com/water-systems/illinois/cortland-il0370051 (data as of October 1, 2026).