MILES CITY, Montana Tap Water Quality

What this violation means

Fluoride at the optimal level (~0.7 mg/L) reduces tooth decay, which is why most US utilities add it. The MCL of 4.0 mg/L exists to protect against skeletal fluorosis from naturally high-fluoride groundwater, while the EPA's secondary standard of 2.0 mg/L addresses dental fluorosis in children.

Recommended precautions

• →Reverse osmosis removes fluoride; standard carbon filters do NOT.
• →If your child uses fluoride toothpaste and drinks fluoridated water, supervise brushing to limit ingestion.
• →Bone meal supplements often contain fluoride and should be used cautiously.

What this violation means

Total coliform bacteria are themselves usually harmless, but their presence signals that the water distribution system has a vulnerability — typically a cracked pipe, loss of pressure, or back-siphonage — that could allow disease-causing pathogens to enter. Repeated coliform-positive samples trigger mandatory utility investigation.

Recommended precautions

• →If your utility issues a boil-water advisory, boil all drinking and cooking water for at least one minute.
• →Use bottled water until the advisory is lifted.
• →Ice from icemakers and beverages made before the advisory should be discarded.
• →UV light and chlorination both kill coliform bacteria — most home filters do not.