Oslo, MN · Marshall County
Oslo Water System
Consumer Confidence Report status
Oslo must publish a Consumer Confidence Report — the annual drinking water quality report covering calendar year 2026 — by July 1, 2027.
As of August 1, 2026, EPA's federal records show no open violations for Oslo.
Data sourced from the EPA ECHO database (SDWA bulk download), last refreshed August 1, 2026. This is a record-keeping and public-information tool — it does not replace Minnesota’s official records. Always confirm current status with Minnesota before making decisions based on this information.
System facts
- System ID (PWSID)
- MN1450008
- System type
- Community Water System
- Population served
- 242
- Service connections
- 186
- Ownership
- local government
- Water source
- groundwater (wells)
Oslo is one of 739 community water systems in Minnesota in the 500 or fewer people size category, serving 242 people from groundwater.
As of August 1, 2026, its federal record holds 3 entries between 2014 and 2017, all of which EPA lists as closed. Nothing has been added since 2017.
All 3 are monitoring and reporting requirements — the category that accounts for about four in five of all violations in EPA's national dataset — rather than findings about the water itself. The record involves the Lead and Copper Rule, the Total Coliform Rules, and the Stage 1 Disinfectants and Disinfection Byproducts Rule.
Violation history
Follow-up Or Routine LCR Tap M/R
—Lead and Copper Rule
October 1, 2017 – July 17, 2018
ResolvedMonitoring, Routine Major (TCR)
—Coliform (TCR)
July 1, 2014 – September 30, 2014
ResolvedMonitoring and Reporting (DBP)
—Chlorine
July 1, 2014 – September 30, 2014
Resolved
Resolved addressed and confirmed by the state
| Period | Violation | Contaminant / rule | Health-based | Status |
|---|---|---|---|---|
| October 1, 2017 – July 17, 2018 | Follow-up Or Routine LCR Tap M/R | Lead and Copper Rule | — | Resolved |
| July 1, 2014 – September 30, 2014 | Monitoring, Routine Major (TCR) | Coliform (TCR) | — | Resolved |
| July 1, 2014 – September 30, 2014 | Monitoring and Reporting (DBP) | Chlorine | — | Resolved |
Resolved addressed and confirmed by the state
Enforcement actions
- July 17, 2018State Compliance achieved1 linked violation
- February 23, 2018State Public Notification received1 linked violation
- January 16, 2018State Formal Notice of Violation issued1 linked violation
- January 16, 2018State Public Notification requested1 linked violation
- December 11, 2017State Violation/Reminder Notice1 linked violation
- October 16, 2017State Violation/Reminder Notice1 linked violation
- September 1, 2017State Violation/Reminder Notice1 linked violation
- October 28, 2014State Formal Notice of Violation issued3 linked violations
Common questions
Is Oslo required to publish a Consumer Confidence Report?
- Yes. Oslo is a community water system, and federal rules (40 CFR 141 Subpart O) require every community water system to publish a Consumer Confidence Report each year.
When is Oslo’s next Consumer Confidence Report due?
- Oslo’s next Consumer Confidence Report is due by July 1, 2027. The report covers calendar year 2026.
Does Oslo have any open drinking water violations on record?
- As of August 1, 2026, EPA's federal records show no open violations for Oslo.
What is a Consumer Confidence Report?
- A Consumer Confidence Report (CCR) is the annual drinking water quality report that community water systems must provide to the people they serve. It lists the contaminants detected in the system’s water during the year, where the water comes from, and how the results compare with federal limits. EPA’s revised CCR rule takes effect January 1, 2027, and the first reports in the new format are due July 1, 2027.
Contact
Oslo City Council
2186953841
Oslo, MN 56744-0187