C44/100
Big Sky Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 4,132 residents · Montana
What's In Big Sky's Tap Water?
31
Contaminants Tested
0
Exceed EPA Limits
1
Above EPA Goals
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | 0.005 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
1
Violation (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: April 1, 2025 – June 30, 2025Enforcement: 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
BIG SKY COUNTY WATER AND SEWER DIST 363
Population Served
4,132
Water Source
Groundwater
System ID
MT0002385
Frequently Asked Questions About Big Sky Water
Is Big Sky tap water safe to drink?
Big Sky, Montana tap water receives a grade of C (44/100), which is considered fair. 0 contaminant(s) exceed EPA maximum contaminant levels and 33 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Big Sky's water?
Of the 31 contaminants tested in Big Sky'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 Big Sky have any water quality violations?
Yes, Big Sky has 33 EPA violation(s) on record, with the most recent in 2025. Violation types include MR, Other, MCL. 5 of these are health-based violations, which are the most serious category.
Do I need a water filter in Big Sky?
Big Sky 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 Big Sky's tap water come from?
Big Sky's drinking water is sourced from groundwater and supplied by BIG SKY COUNTY WATER AND SEWER DIST 363. The system serves approximately 4,132 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Big Sky'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. Big Sky'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 Big Sky's water compare to other cities in Montana?
Big Sky's water quality score of 44/100 earns a grade of C, which is considered fair. This is a below-average score that indicates room for improvement. Visit our Montana state page to see how all cities in the state compare.
What should I do if I'm concerned about Big Sky's water quality?
If you have concerns about Big Sky'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 (BIG SKY COUNTY WATER AND SEWER DIST 363) 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.