Public water system · WI1281263
ActiveAztalan Bio
At a glance
Aztalan Bio (PWSID WI1281263) is an active non-transient non-community water system in Jefferson County, Wisconsin. It reports serving 99 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 6 violations for this system; none is health-based, and the most recent began in January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
99
Service connections
1
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Aztalan Bio compare with other water systems in Jefferson County?
By EPA's size categories, Aztalan Bio is a very small system (500 people or fewer). Jefferson County has 195 active public water systems. Its population served is well below the county average of 453 people per system, and accounts for 0.1% of the 88,343 people reported by systems filed under the county. Across Wisconsin, the 11,056 active systems average 469 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Aztalan Bio is well below that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. Wisconsin has 891 active non-transient non-community water systems, 8.1% of the state's 11,056 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 10,978 Wisconsin systems (99%) list groundwater as their primary source.
Who owns and regulates Aztalan Bio?
EPA lists Aztalan Bio as privately owned. The WI state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 152 of the 195 active systems in Jefferson County (78%) are also privately owned.
Does Aztalan Bio have drinking water violations?
EPA's records list 6 violations for this system; none is health-based, and the most recent began in January 2026. The violations listed here began between June 2025 and January 2026. By type: 4 monitoring and reporting and 2 monitoring. The contaminant or rule involved most often is Nitrate (3 of them). EPA lists 3 as archived, 2 as resolved and 1 as unaddressed. 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. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2026-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Archived |
| 2025-10-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Archived |
| 2025-07-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2025-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Archived |
| 2025-06-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Unaddressed |
All 6 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.
Aztalan Bio: frequently asked questions
Who runs Aztalan Bio?
Aztalan Bio (PWSID WI1281263) is a non-transient non-community water system privately owned. It is regulated by the WI state drinking water program.
How many people does Aztalan Bio serve?
Aztalan Bio reports serving 99 people through 1 service connection in Jefferson County, Wisconsin.
Where does Aztalan Bio 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 Aztalan Bio have any drinking water violations?
EPA's records list 6 violations for this system; none is health-based, and the most recent began in January 2026. 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 Aztalan Bio'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 6 violations for this system; none is health-based, and the most recent began in January 2026. For current results, consult EPA ECHO, or the WI state drinking water program.
Where can I find Aztalan Bio's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Aztalan Bio is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Jefferson County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Watertown Waterworks | Jefferson | 23,945 | Community | Groundwater |
| Fort Atkinson Waterworks | Jefferson | 12,390 | Community | Groundwater |
| Jefferson Waterworks | Jefferson | 7,926 | Community | Groundwater |
| Lake Mills Waterworks | Jefferson | 6,211 | Community | Groundwater |
| Waterloo Waterworks | Jefferson | 3,520 | Community | Groundwater |
| Johnson Creek Waterworks | Jefferson | 3,318 | 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, “Aztalan Bio, PWSID WI1281263, Wisconsin”, https://aquacensus.com/water-systems/wisconsin/aztalan-bio-wi1281263 (data as of October 1, 2026).