Exceeds EPA Limit Fluoride EXCEEDS EPA LIMIT

Fluoride in Williston, ND Drinking Water

Fluoride data for Williston, North Dakota · 33,969 residents · 3 ZIP codes

EPA records show Fluoride detections in Williston, North Dakota water samples.

44.72 ppb
Max Level Detected
44.72 ppb
Average Level
4.0 mg/L (MCL) / 2.0 mg/L (SMCL)
EPA MCL
Moderate
Health Risk
Reverse Osmosis or Activated Alumina
Best Filter Method

Data: EPA SDWIS, CCR Reports, ECHO Last verified: 2026-04-05

Fluoride in Williston Tap Water

Fluoride has been detected in Williston, North Dakota drinking water at a maximum level of 44.72 ppb — below the EPA MCL of 4.0 mg/L (MCL) / 2.0 mg/L (SMCL).

This analysis covers 33,969 residents across 3 ZIP codes in Williston.

Williston's overall water quality grade is C (63/100).

Is Fluoride in Williston Water Safe?

Fluoride levels in parts of Williston exceed the EPA MCL of 4.0 mg/L (MCL) / 2.0 mg/L (SMCL). The EPA requires water systems to take corrective action when this limit is exceeded.

If you live in an affected ZIP code, consider installing a reverse osmosis or activated alumina filter certified under NSF 58 and testing your water independently.

Fluoride Levels by ZIP Code

ZIP Code Fluoride Level EPA Limit Status
58801 44.72 ppm 4.0 mg/L (MCL) / 2.0 mg/L (SMCL) OK
58802 44.72 ppm 4.0 mg/L (MCL) / 2.0 mg/L (SMCL) OK
58803 44.72 ppm 4.0 mg/L (MCL) / 2.0 mg/L (SMCL) OK

Average fluoride level across Williston: 44.72 ppb

Health Effects of Fluoride

  • Skeletal fluorosis at levels above 4 mg/L (bone pain, joint stiffness)
  • Dental fluorosis in children at levels above 2 mg/L
  • At 0.7 mg/L (water fluoridation level), helps prevent tooth decay
  • Possible thyroid effects at high chronic exposure

Health risk severity: Moderate. Governed by the National Primary Drinking Water Regulations.

How Fluoride Gets Into Drinking Water

  • Intentional water fluoridation (0.7 mg/L target, beneficial)
  • Natural deposits in certain rock formations
  • Industrial discharge (aluminum, fertilizer production)
  • Naturally elevated in some groundwater (especially arid regions)

What to Do About Fluoride in Williston Water

  1. Reverse osmosis removes 90%+ of fluoride
  2. Activated alumina filters are effective for fluoride
  3. Bone char carbon can reduce fluoride
  4. Standard activated carbon filters do NOT remove fluoride

Look for filters certified under NSF 58 for fluoride removal.

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