THOMPSON FALLS CITY OF

Montana — Community Water System — PWSID: MT0000341

System Information

PWSID	MT0000341
System Name	THOMPSON FALLS CITY OF
System Type	Community Water System
Water Source	Ground Water
Activity Status	Active
Owner Type	Local
EPA Region	08
Serves School	No
Wholesaler	No
First Reported	Feb 13, 1979
Last Reported	Mar 26, 2026

Location & Contact

State	Montana
City	THOMPSON FALLS
ZIP Code	59813
Address	PO BOX 99
Organization	HARNETT, JONATHAN O
Phone	406-827-3557

Population & Service

Population Served	1,950
Service Connections	719

Drinking Water Violations (38)

This water system has 38 violations recorded in the EPA SDWIS database.

Begin Date	End Date	Category	Health-Based	Major	Measured	Federal MCL	State MCL	Status	Return to Compliance	Rule
Jul 1, 2015	—	Other	No	No	—	—	—	Resolved	Jul 17, 2015	—
Jul 1, 2015	—	Other	No	No	—	—	—	Resolved	Jul 17, 2015	—
Nov 1, 2005	Nov 30, 2005	MR	No	No	—	5% of samples	—	Resolved	Nov 30, 2005	—
Nov 1, 2005	Nov 30, 2005	MR	No	No	—	5% of samples	—	Resolved	Nov 30, 2005	—
Nov 1, 2005	Nov 30, 2005	MR	No	No	—	5% of samples	—	Resolved	Nov 30, 2005	—
Dec 1, 1999	Dec 31, 1999	TT	Yes	No	—	—	—	Resolved	Dec 31, 1999	—
Dec 1, 1999	Dec 31, 1999	TT	Yes	No	—	—	—	Resolved	Dec 31, 1999	—
Dec 1, 1999	Dec 31, 1999	TT	Yes	No	—	—	—	Resolved	Dec 31, 1999	—
Apr 1, 1997	Apr 30, 1997	MR	No	No	—	5% of samples	—	Resolved	Apr 30, 1997	—
Jan 1, 1997	Jan 31, 1997	MR	No	No	—	5% of samples	—	Resolved	Jan 31, 1997	—
Jan 1, 1996	Dec 31, 1996	MR	No	Yes	—	10 mg/L	—	Resolved	Dec 31, 1996	—
Oct 1, 1994	Oct 31, 1994	MR	No	No	—	5% of samples	—	Resolved	Oct 31, 1994	—
Jun 1, 1994	Jun 30, 1994	MR	No	No	—	5% of samples	—	Resolved	Jun 30, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	0.002 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	0.2 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	—	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	0.004 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	0.002 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	4.0 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	0.05 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	0.006 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	10 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	0.010 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	2 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	0.005 mg/L	—	Resolved	Dec 31, 1994	—
Jan 1, 1994	Dec 31, 1994	MR	No	Yes	—	0.1 mg/L	—	Resolved	Dec 31, 1994	—
Jul 1, 1992	Jul 31, 1992	MR	No	No	—	5% of samples	—	Resolved	Jul 31, 1992	—
Oct 1, 1981	Sep 30, 1982	MR	No	Yes	—	0.005 mg/L	—	Archived	Sep 30, 1982	—
Oct 1, 1981	Sep 30, 1982	MR	No	Yes	—	0.010 mg/L	—	Archived	Sep 30, 1982	—
Oct 1, 1981	Sep 30, 1982	MR	No	Yes	—	0.1 mg/L	—	Archived	Sep 30, 1982	—
Oct 1, 1981	Sep 30, 1982	MR	No	Yes	—	10 mg/L	—	Archived	Sep 30, 1982	—
Oct 1, 1981	Sep 30, 1982	MR	No	Yes	—	0.05 mg/L	—	Archived	Sep 30, 1982	—
Oct 1, 1981	Sep 30, 1982	MR	No	Yes	—	2 mg/L	—	Archived	Sep 30, 1982	—
Oct 1, 1981	Sep 30, 1982	MR	No	Yes	—	4.0 mg/L	—	Archived	Sep 30, 1982	—
Oct 1, 1981	Sep 30, 1982	MR	No	Yes	—	0.002 mg/L	—	Archived	Sep 30, 1982	—
—	—	—	No	No	—	—	—	—	—	—
—	—	—	No	No	—	—	—	—	—	—
—	—	—	No	No	—	—	—	—	—	—

About This Water System

Public water system data comes from the EPA Safe Drinking Water Information System (SDWIS). Systems with violations must notify customers. Contact your water utility for the latest annual water quality report.

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