F0/100
Fort Thompson Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 1,357 residents · South Dakota
What's In Fort Thompson's Tap Water?
1
Contaminants Tested
0
Exceed EPA Limits
1
Above EPA Goals
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | < 0.001 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
5
Violations (last 5yr)
0
Unresolved
1
Health-Related
TIER 3Resolved
Failed Level 2 Assessment under Revised Total Coliform Rule
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: April 1, 2024 – June 30, 2024Rule: Stage 2 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved
Failed Level 2 Assessment under Revised Total Coliform Rule
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: April 1, 2024 – June 30, 2024Rule: Stage 2 DBPREnforcement: Resolving — corrective action underway
TIER 2Resolved
Violation related to Lead and Copper Rule
When: September 8, 2022 – March 17, 2023Rule: Surface Water Treatment RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2022 – December 31, 2022Enforcement: Resolving — corrective action underway
TIER 3Resolved
Monitoring Violation
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: June 1, 2021 – June 30, 2021Rule: Total Coliform RuleEnforcement: Resolving — corrective action underway
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
FORT THOMPSON WATER SYSTEM
Population Served
1,357
Water Source
Surface Water
System ID
084690440
Frequently Asked Questions About Fort Thompson Water
Is Fort Thompson tap water safe to drink?
Fort Thompson, South Dakota tap water receives a grade of F (0/100), which is considered failing. 0 contaminant(s) exceed EPA maximum contaminant levels and 152 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Fort Thompson's water?
Of the 1 contaminants tested in Fort Thompson's water supply, the most notable include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Fort Thompson have any water quality violations?
Yes, Fort Thompson has 152 EPA violation(s) on record, with the most recent in 2024. Violation types include MR, TT, MON. 14 of these are health-based violations, which are the most serious category.
Do I need a water filter in Fort Thompson?
Fort Thompson 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. 1 contaminant(s) exceed these stricter goals.
Where does Fort Thompson's tap water come from?
Fort Thompson's drinking water is sourced from surface water and supplied by FORT THOMPSON WATER SYSTEM. The system serves approximately 1,357 people. Surface water sources include rivers, lakes, and reservoirs.
How often is Fort Thompson'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. Fort Thompson'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 Fort Thompson's water compare to other cities in South Dakota?
Fort Thompson's water quality score of 0/100 earns a grade of F, which is considered failing. This is a concerning score that suggests significant water quality issues. Visit our South Dakota state page to see how all cities in the state compare.
What should I do if I'm concerned about Fort Thompson's water quality?
If you have concerns about Fort Thompson'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 (FORT THOMPSON WATER SYSTEM) 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.