Public water system · CO0102100
ActiveAlamosa City of
At a glance
City of Alamosa (PWSID CO0102100) is an active community water system in Alamosa County, Colorado. It reports serving 11,271 people through 3,463 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, 11 are health-based, and the most recent began in November 2008.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
11,271
Service connections
3,463
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does City of Alamosa compare with other water systems in Alamosa County?
By EPA's size categories, City of Alamosa is a large system (10,001 to 100,000 people). Alamosa County has 17 active public water systems, and City of Alamosa is the largest of them by population served. Its population served is about 12 times the county average of 962 people per system, and accounts for 69% of the 16,356 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 City of Alamosa is about 68% 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. Colorado has 1,068 active community water systems, 48% of the state's 2,207 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,437 Colorado systems (65%) list groundwater as their primary source.
Who owns and regulates City of Alamosa?
EPA lists City of Alamosa 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. 4 of the 17 active systems in Alamosa County (24%) are also owned by a local government.
Does City of Alamosa have drinking water violations?
Of the 12 most recent violations in EPA's records, 11 are health-based, and the most recent began in November 2008. The violations listed here began between January 2008 and November 2008. By type: 11 contaminant level above the legal limit and 1 monitoring and reporting. The contaminant or rule involved most often is Arsenic (12 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 |
|---|---|---|---|---|
| 2008-11-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 2008-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2008-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2008-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2008-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2008-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2008-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2008-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2008-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2008-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2008-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2008-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | 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.
City of Alamosa: frequently asked questions
Who runs City of Alamosa?
City of Alamosa (PWSID CO0102100) is a community water system owned by a local government. It is regulated by the CO state drinking water program.
How many people does City of Alamosa serve?
City of Alamosa reports serving 11,271 people through 3,463 service connections in Alamosa County, Colorado.
Where does City of Alamosa 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 City of Alamosa have any drinking water violations?
Of the 12 most recent violations in EPA's records, 11 are health-based, and the most recent began in November 2008. 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 City of Alamosa'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, 11 are health-based, and the most recent began in November 2008. For current results, consult the system's annual water quality report, EPA ECHO, or the CO state drinking water program.
Where can I find City of Alamosa's water quality report?
As a community water system, City of Alamosa 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 Alamosa County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| East Alamosa | Alamosa | 1,453 | Community | Purchased groundwater |
| Great Sand Dunes Hq | Alamosa | 1,400 | Non-transient non-community | Groundwater |
| Ramble Cg | Alamosa | 601 | Transient non-community | Groundwater |
| Sangre De Cristo Lane Seven School | Alamosa | 445 | Non-transient non-community | Groundwater |
| Great Sand Dunes Pinon Flats Cg | Alamosa | 250 | Transient non-community | Groundwater |
| Wagon Wheel MHP | Alamosa | 160 | 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, “Alamosa City of, PWSID CO0102100, Colorado”, https://aquacensus.com/water-systems/colorado/alamosa-city-of-co0102100 (data as of October 1, 2026).