Public water system · CO0135476
ActiveCarter Lake Filter Plant
At a glance
Carter Lake Filter Plant (PWSID CO0135476) is an active community water system in Larimer County, Colorado. It reports serving 11 people through 10,730 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. EPA's records list 5 violations for this system; none is health-based, and the most recent began in January 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
11
Service connections
10,730
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does Carter Lake Filter Plant compare with other water systems in Larimer County?
By EPA's size categories, Carter Lake Filter Plant is a very small system (500 people or fewer). Larimer County has 134 active public water systems. Its population served is well below the county average of 3,842 people per system, and accounts for less than 0.1% of the 514,860 people reported by systems filed under the county. Across Colorado, the 2,207 active systems average 3,400 people each. Nationally, the average active community water system reports serving 6,703 people, so Carter Lake Filter Plant 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. Colorado has 1,068 active community water systems, 48% of the state's 2,207 active systems. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 228 Colorado systems (10%) list surface water as their primary source.
Who owns and regulates Carter Lake Filter Plant?
EPA lists Carter Lake Filter Plant as owned by a local government. The CO state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 21 of the 134 active systems in Larimer County (16%) are also owned by a local government.
Does Carter Lake Filter Plant have drinking water violations?
EPA's records list 5 violations for this system; none is health-based, and the most recent began in January 2025. The violations listed here began between April 2008 and January 2025. By type: 4 monitoring and reporting and 1 public notice, recordkeeping or other. The contaminants or rules involved are Lead and Copper Rule, Public Notice, Interim Enhanced Surface Water Treatment Rule and Chlorine dioxide. EPA lists 5 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 |
|---|---|---|---|---|
| 2025-01-01 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2018-04-28 | Public notice, recordkeeping or otherPublic Notification Violation without NPDWR Violation · code 76 | Public Noticecode 7500 | No | Resolved |
| 2012-01-01 | Monitoring and reportingMonitoring, Turbidity (Enhanced SWTR) · code 38 | Interim Enhanced Surface Water Treatment Rulecode 0300 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorine dioxidecode 1008 | No | Resolved |
| 2008-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloritecode 1009 | No | Resolved |
All 5 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.
Carter Lake Filter Plant: frequently asked questions
Who runs Carter Lake Filter Plant?
Carter Lake Filter Plant (PWSID CO0135476) is a community water system owned by a local government. It is regulated by the CO state drinking water program.
How many people does Carter Lake Filter Plant serve?
Carter Lake Filter Plant reports serving 11 people through 10,730 service connections in Larimer County, Colorado.
Where does Carter Lake Filter Plant get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does Carter Lake Filter Plant have any drinking water violations?
EPA's records list 5 violations for this system; none is health-based, and the most recent began in January 2025. 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 Carter Lake Filter Plant'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 5 violations for this system; none is health-based, and the most recent began in January 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the CO state drinking water program.
Where can I find Carter Lake Filter Plant's water quality report?
As a community water system, Carter Lake Filter Plant 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 Larimer County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Ft Collins City of | Larimer | 179,901 | Community | Surface water |
| Loveland City of | Larimer | 91,077 | Community | Surface water |
| Ft Collins Loveland Wd | Larimer | 63,532 | Community | Purchased surface water |
| East Larimer County Wd | Larimer | 27,944 | Community | Purchased surface water |
| Csu Main and West Housing Campus | Larimer | 27,375 | Community | Purchased surface water |
| Little Thompson Wd | Larimer | 25,654 | Community | Purchased surface water |
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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, “Carter Lake Filter Plant, PWSID CO0135476, Colorado”, https://aquacensus.com/water-systems/colorado/carter-lake-filter-plant-co0135476 (data as of October 1, 2026).