Public Water Partners

GREAT FALLS, MT · Cascade County

OASIS WATER SERVICE Water System

Inactive system

This water system is marked inactive in EPA’s federal records as of December 29, 2015. It is no longer an operating public water system under this PWSID, and no compliance deadlines — including the 2027 Consumer Confidence Report rule — apply to it.

If you are a resident looking for your current water provider, see water systems in Cascade County, MT.

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 Montana’s official records. Always confirm current status with Montana before making decisions based on this information.

System facts

System ID (PWSID)
MT0003946
System type
Community Water System
Population served
45
Service connections
1
Ownership
privately owned
Water source
surface water (rivers, lakes, or reservoirs)

OASIS WATER SERVICE is one of 1,084 community water systems in Montana in the 500 or fewer people size category, formerly serving 45 people from surface water.

EPA's federal records list this system as inactive in 2015; the record below is historical.

As of August 1, 2026, its federal record holds 16 entries between 1998 and 2015, all of which EPA lists as closed. Nothing has been added since 2015.

Of the 16, 10 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 Total Coliform Rules, the Consumer Confidence Rule, and the Lead and Copper Rule.

Violation history

  • Monitoring, Routine Major (TCR)

    —

    Coliform (TCR)

    November 1, 2015 – November 30, 2015

    Resolved

  • Consumer Confidence Report Inadequate Reporting

    —

    Consumer Confidence Rule

    October 1, 2015 – December 11, 2015

    Resolved

  • Consumer Confidence Report Complete Failure to Report

    —

    Consumer Confidence Rule

    July 1, 2015 – December 29, 2015

    Archived

  • Consumer Confidence Report Inadequate Reporting

    —

    Consumer Confidence Rule

    October 1, 2014 – January 29, 2015

    Resolved

  • Consumer Confidence Report Complete Failure to Report

    —

    Consumer Confidence Rule

    July 1, 2014 – January 29, 2015

    Resolved

  • Lead Consumer Notice

    —

    Lead and Copper Rule

    January 1, 2014 – December 29, 2015

    Archived

  • Consumer Confidence Report Inadequate Reporting

    —

    Consumer Confidence Rule

    October 1, 2013 – January 28, 2014

    Resolved

  • Lead Consumer Notice

    —

    Lead and Copper Rule

    January 1, 2011 – May 12, 2011

    Resolved

  • Initial Tap Sampling for Pb and Cu

    —

    Lead and Copper Rule

    August 15, 2007 – August 29, 2007

    Resolved

  • Initial Tap Sampling for Pb and Cu

    —

    Lead and Copper Rule

    October 1, 2006 – August 29, 2007

    Resolved

  • Consumer Confidence Report Complete Failure to Report

    —

    Consumer Confidence Rule

    July 1, 2006 – October 22, 2008

    Resolved

  • Monitoring, Routine Major (TCR)

    —

    Coliform (TCR)

    May 1, 2002 – May 31, 2002

    Resolved

  • Monitoring, Routine Major (TCR)

    —

    Coliform (TCR)

    November 1, 2001 – November 30, 2001

    Resolved

  • Monitoring, Routine Major (TCR)

    —

    Coliform (TCR)

    October 1, 1999 – October 31, 1999

    Resolved

  • Monitoring, Routine Major (TCR)

    —

    Coliform (TCR)

    October 1, 1998 – October 31, 1998

    Resolved

  • Monitoring, Routine Major (TCR)

    —

    Coliform (TCR)

    August 1, 1998 – August 31, 1998

    Resolved

Resolved addressed and confirmed by the stateArchived closed in EPA's records (typically due to age or a data correction)

Enforcement actions

Last known contact on file (system is inactive)

CAMPBELL, JASON

406-727-2800

GREAT FALLS, MT 59403