Public water system · IN5245046
ActiveCuii - Twin Lakes
At a glance
Cuii - Twin Lakes (PWSID IN5245046) is an active community water system in Lake County, Indiana. It reports serving 8,000 people through 3,253 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, none is health-based, and the most recent began in January 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
8,000
Service connections
3,253
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Cuii - Twin Lakes compare with other water systems in Lake County?
By EPA's size categories, Cuii - Twin Lakes is a medium system (3,301 to 10,000 people). Lake County has 110 active public water systems. Its population served is about 65% above the county average of 4,845 people per system, and accounts for 1.5% of the 532,973 people reported by systems filed under the county. Across Indiana, the 3,969 active systems average 1,456 people each. Nationally, the average active community water system reports serving 6,703 people, so Cuii - Twin Lakes is about 19% above 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. Indiana has 770 active community water systems, 19% of the state's 3,969 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 3,769 Indiana systems (95%) list groundwater as their primary source.
Who owns and regulates Cuii - Twin Lakes?
EPA lists Cuii - Twin Lakes as privately owned. The IN state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 86 of the 110 active systems in Lake County (78%) are also privately owned.
Does Cuii - Twin Lakes have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2024. The violations listed here began between January 1998 and January 2024. By type: 10 monitoring and reporting and 2 reporting. The contaminant or rule involved most often is Revised Total Coliform Rule (2 of them). EPA lists 10 as resolved and 2 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 |
|---|---|---|---|---|
| 2024-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Archived |
| 2024-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Archived |
| 2023-01-01 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2021-11-11 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2001-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) phthalatecode 2039 | No | Resolved |
| 1999-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) phthalatecode 2039 | No | Resolved |
| 1998-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 2,4-Dcode 2105 | No | Resolved |
| 1998-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Atrazinecode 2050 | No | Resolved |
| 1998-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Alachlor (Lasso)code 2051 | No | Resolved |
| 1998-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Simazinecode 2037 | No | Resolved |
| 1998-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Simazinecode 2037 | No | Resolved |
| 1998-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Atrazinecode 2050 | 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.
Cuii - Twin Lakes: frequently asked questions
Who runs Cuii - Twin Lakes?
Cuii - Twin Lakes (PWSID IN5245046) is a community water system privately owned. It is regulated by the IN state drinking water program.
How many people does Cuii - Twin Lakes serve?
Cuii - Twin Lakes reports serving 8,000 people through 3,253 service connections in Lake County, Indiana.
Where does Cuii - Twin Lakes 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 Cuii - Twin Lakes 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 January 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 Cuii - Twin Lakes' 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 January 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the IN state drinking water program.
Where can I find Cuii - Twin Lakes' water quality report?
As a community water system, Cuii - Twin Lakes 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 Lake County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Indiana American Water - Northwest | Lake | 210,510 | Community | Surface water |
| Hammond Water Works Department | Lake | 78,384 | Community | Surface water |
| Crown Point Water Works | Lake | 30,000 | Community | Purchased surface water |
| Schererville Water Department | Lake | 30,000 | Community | Purchased surface water |
| East Chicago Water Works | Lake | 26,370 | Community | Surface water |
| St. John Municipal Water Utility | Lake | 25,700 | 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, “Cuii - Twin Lakes, PWSID IN5245046, Indiana”, https://aquacensus.com/water-systems/indiana/cuii-twin-lakes-in5245046 (data as of October 1, 2026).