B66/100
Thompson Falls Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 1,950 residents · Montana
What's In Thompson Falls's Tap Water?
1
Contaminants Tested
0
Exceed EPA Limits
0
Above EPA Goals
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2015.
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Water Utility Details
THOMPSON FALLS CITY OF
Population Served
1,950
Water Source
Groundwater
System ID
MT0000341
Frequently Asked Questions About Thompson Falls Water
Is Thompson Falls tap water safe to drink?
Thompson Falls, Montana tap water receives a grade of B (66/100), which is considered good. Out of 1 contaminants tested, none exceed EPA maximum contaminant levels (MCLs). While the water meets federal standards, some residents may still choose to use a filter for additional peace of mind.
What contaminants are in Thompson Falls's water?
1 contaminants were tested in Thompson Falls's water supply. No contaminants exceed EPA legal limits (MCLs) or health goals (MCLGs), which is a positive indicator of water quality.
Does Thompson Falls have any water quality violations?
Yes, Thompson Falls has 30 EPA violation(s) on record, with the most recent in 2015. Violation types include Other, MR, TT. 1 of these are health-based violations, which are the most serious category.
Do I need a water filter in Thompson Falls?
Thompson Falls water meets EPA standards, so a filter is not strictly necessary. However, some residents prefer the added security of a water filter. EPA health goals (MCLGs) are stricter than legal limits and are set at levels with zero expected health risk. All contaminants are within health goals.
Where does Thompson Falls's tap water come from?
Thompson Falls's drinking water is sourced from groundwater and supplied by THOMPSON FALLS CITY OF. The system serves approximately 1,950 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Thompson Falls's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Thompson Falls's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Thompson Falls's water compare to other cities in Montana?
Thompson Falls's water quality score of 66/100 earns a grade of B, which is considered good. This is an above-average score compared to many cities nationwide. Visit our Montana state page to see how all cities in the state compare.
What should I do if I'm concerned about Thompson Falls's water quality?
If you have concerns about Thompson Falls's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (THOMPSON FALLS CITY OF) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.