F0/100
Twin Falls Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 56,121 residents · Idaho
What's In Twin Falls's Tap Water?
66
Contaminants Tested
0
Exceed EPA Limits
1
Above EPA Goals
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
vanadium | 31.30 µg/L | — | Above Goal |
EPA Violation History
4
Violations (last 5yr)
0
Unresolved
0
Health-Related
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, 2023 – December 31, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved
Consumer confidence report — inadequate or unavailable
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: July 1, 2022 – December 11, 2024Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Consumer confidence report — inadequate or unavailable
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: July 1, 2022 – December 11, 2024Rule: Ground Water 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
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
TWIN FALLS CITY OF
Population Served
56,121
Water Source
Groundwater
System ID
ID5420058
Frequently Asked Questions About Twin Falls Water
Is Twin Falls tap water safe to drink?
Twin Falls, Idaho tap water receives a grade of F (0/100), which is considered failing. 0 contaminant(s) exceed EPA maximum contaminant levels and 58 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Twin Falls's water?
Of the 66 contaminants tested in Twin Falls's water supply, the most notable include vanadium. 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 Twin Falls have any water quality violations?
Yes, Twin Falls has 58 EPA violation(s) on record, with the most recent in 2023. Violation types include MR, Other, MCL. 35 of these are health-based violations, which are the most serious category.
Do I need a water filter in Twin Falls?
Twin 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. 1 contaminant(s) exceed these stricter goals.
Where does Twin Falls's tap water come from?
Twin Falls's drinking water is sourced from groundwater and supplied by TWIN FALLS CITY OF. The system serves approximately 56,121 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Twin 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. Twin 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 Twin Falls's water compare to other cities in Idaho?
Twin Falls'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 Idaho state page to see how all cities in the state compare.
What should I do if I'm concerned about Twin Falls's water quality?
If you have concerns about Twin 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 (TWIN 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.