Public water system · CO0135477
ActiveLittle Thompson Wd
At a glance
Little Thompson Wd (PWSID CO0135477) is an active community water system in Larimer County, Colorado. It reports serving 25,654 people through 10,303 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in August 2005.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
25,654
Service connections
10,303
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Little Thompson Wd compare with other water systems in Larimer County?
By EPA's size categories, Little Thompson Wd is a large system (10,001 to 100,000 people). Larimer County has 134 active public water systems, and Little Thompson Wd is the 6th-largest of them by population served. Its population served is about 6.7 times the county average of 3,842 people per system, and accounts for 5% 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 Little Thompson Wd is about 3.8 times 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 337 Colorado systems (15%) list purchased surface water as their primary source.
Who owns and regulates Little Thompson Wd?
EPA lists Little Thompson Wd 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 Little Thompson Wd have drinking water violations?
EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in August 2005. The violations listed here began between June 1997 and August 2005. By type: 1 contaminant level above the legal limit and 1 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (2 of them). EPA lists 2 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 |
|---|---|---|---|---|
| 2005-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1997-06-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 2 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.
Little Thompson Wd: frequently asked questions
Who runs Little Thompson Wd?
Little Thompson Wd (PWSID CO0135477) is a community water system owned by a local government. It is regulated by the CO state drinking water program.
How many people does Little Thompson Wd serve?
Little Thompson Wd reports serving 25,654 people through 10,303 service connections in Larimer County, Colorado.
Where does Little Thompson Wd get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Little Thompson Wd have any drinking water violations?
EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in August 2005. 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 Little Thompson Wd'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 2 violations for this system; 1 is health-based, and the most recent began in August 2005. For current results, consult the system's annual water quality report, EPA ECHO, or the CO state drinking water program.
Where can I find Little Thompson Wd's water quality report?
As a community water system, Little Thompson Wd 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 |
| Estes Park Town of | Larimer | 16,722 | Community | 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, “Little Thompson Wd, PWSID CO0135477, Colorado”, https://aquacensus.com/water-systems/colorado/little-thompson-wd-co0135477 (data as of October 1, 2026).