Public water system · WY5601645
ActiveMile-Hi I&S District
At a glance
Mile-Hi I&S District (PWSID WY5601645) is an active community water system in Natrona County, Wyoming. It reports serving 48 people through 45 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's records list 4 violations for this system; 1 is health-based, and the most recent began in April 2020.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
48
Service connections
45
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Mile-Hi I&S District compare with other water systems in Natrona County?
By EPA's size categories, Mile-Hi I&S District is a very small system (500 people or fewer). Natrona County has 48 active public water systems. Its population served is well below the county average of 1,680 people per system, and accounts for less than 0.1% of the 80,646 people reported by systems filed under the county. Across Wyoming, the 775 active systems average 838 people each. Nationally, the average active community water system reports serving 6,703 people, so Mile-Hi I&S District 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. Wyoming has 332 active community water systems, 43% of the state's 775 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 79 Wyoming systems (10%) list purchased surface water as their primary source.
Who owns and regulates Mile-Hi I&S District?
EPA lists Mile-Hi I&S District as owned by a local government. The WY state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 18 of the 48 active systems in Natrona County (38%) are also owned by a local government.
Does Mile-Hi I&S District have drinking water violations?
EPA's records list 4 violations for this system; 1 is health-based, and the most recent began in April 2020. The violations listed here began between October 2015 and April 2020. By type: 2 public notice, recordkeeping or other, 1 required treatment not met and 1 monitoring and reporting. The contaminant or rule involved most often is Lead and Copper Rule (2 of them). EPA lists 4 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 |
|---|---|---|---|---|
| 2020-04-01 | Required treatment not metOCCT/SOWT Study/Recommendation · code 57 | Lead and Copper Rulecode 5000 | Yes | Resolved |
| 2018-01-01 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2017-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2015-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
All 4 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.
Mile-Hi I&S District: frequently asked questions
Who runs Mile-Hi I&S District?
Mile-Hi I&S District (PWSID WY5601645) is a community water system owned by a local government. It is regulated by the WY state drinking water program.
How many people does Mile-Hi I&S District serve?
Mile-Hi I&S District reports serving 48 people through 45 service connections in Natrona County, Wyoming.
Where does Mile-Hi I&S District 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 Mile-Hi I&S District have any drinking water violations?
EPA's records list 4 violations for this system; 1 is health-based, and the most recent began in April 2020. 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 Mile-Hi I&S District'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 4 violations for this system; 1 is health-based, and the most recent began in April 2020. For current results, consult the system's annual water quality report, EPA ECHO, or the WY state drinking water program.
Where can I find Mile-Hi I&S District's water quality report?
As a community water system, Mile-Hi I&S District 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 Natrona County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Casper, City of | Natrona | 59,000 | Community | Purchased surface water |
| Mills, City of | Natrona | 4,050 | Community | Groundwater under influence of surface water |
| Bar Nunn, Town of | Natrona | 4,000 | Community | Purchased surface water |
| Evansville, Town of | Natrona | 2,873 | Community | Surface water |
| Vista West Water Company | Natrona | 1,600 | Community | Purchased surface water |
| Pioneer Water & Sewer District | Natrona | 1,500 | 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, “Mile-Hi I&S District, PWSID WY5601645, Wyoming”, https://aquacensus.com/water-systems/wyoming/mile-hi-i-s-district-wy5601645 (data as of October 1, 2026).