Exceeds EPA Limit Nitrate EXCEEDS EPA LIMIT

Nitrate in Hollis, NH Drinking Water

Nitrate data for Hollis, New Hampshire · 8,530 residents · 1 ZIP code

Over the past reporting period, water systems in Hollis, New Hampshire have recorded Nitrate at detectable concentrations in EPA compliance samples.

10 mg/L (as nitrogen)
EPA MCL
2
EPA Violations
High
Health Risk
Reverse Osmosis or Ion Exchange
Best Filter Method

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

Nitrate in Hollis Tap Water

Hollis, New Hampshire has 2 EPA violations related to nitrate in drinking water.

This analysis covers 8,530 residents across 1 ZIP code in Hollis.

Hollis's overall water quality grade is B (73/100).

Is Nitrate in Hollis Water Safe?

Nitrate levels in parts of Hollis exceed the EPA MCL of 10 mg/L (as nitrogen). 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 ion exchange filter certified under NSF 53 / NSF 58 and testing your water independently.

EPA Violations for Nitrate in Hollis

Date Violation Type Status ZIP Code
2022-10-01 Nitrate-Nitrite (Resolved) Resolved 03049
2022-07-01 Nitrate-Nitrite (Resolved) Resolved 03049

Health Effects of Nitrate

  • Methemoglobinemia ("blue baby syndrome") in infants under 6 months
  • Increased risk of colorectal and bladder cancer (long-term)
  • Thyroid disease from chronic exposure
  • Possible reproductive effects

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

How Nitrate Gets Into Drinking Water

  • Agricultural fertilizer runoff
  • Animal feedlot operations and manure
  • Septic system leachate
  • Urban stormwater and wastewater discharge

What to Do About Nitrate in Hollis Water

  1. Reverse osmosis is the most effective method for nitrate removal
  2. Ion exchange systems designed for nitrate can also work
  3. Standard carbon filters do NOT remove nitrate
  4. Boiling water increases nitrate concentration — never boil for nitrate

Look for filters certified under NSF 53 / NSF 58 for nitrate removal.

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