New Hampshire Water Report Card: Worst Water Systems

The most contaminated public water systems in New Hampshire, ranked by PFAS levels, lead, and EPA violations from official EPA data.

Quick Answer

Central Hooksett Water Pct has the highest PFAS in New Hampshire at 28 ppt (7x the EPA limit). Alton Water Works has the highest lead at 210 ppb. The tables below rank the worst systems in each category so you can see how your water compares.

Highest PFAS Levels in New Hampshire

Public water systems in New Hampshire with the highest peak PFAS ("forever chemical") reading in EPA UCMR5 testing (2023-2025). The EPA enforceable limit for PFOA and PFOS is 4 ppt.

#Water SystemLocationPeak PFAS (ppt)Compoundsvs 4 ppt limit
1Central Hooksett Water PctHooksett · 4,650 served2827x
2Aquarion Water/NhMonroe · 18,950 served25.156x
3Pease Trade PortPortsmouth · 9,900 served15.114x
4Exeter Water DeptExeter · 12,236 served1323x
5Jaffrey Water WorksJaffrey · 3,800 served1133x
6Hudson Water DeptHudson · 16,700 served922x
7Portsmouth Water WorksPortsmouth · 33,000 served972x
8Salem Water DeptSalem · 21,000 served8.512x
9Rye Water DistRye · 4,300 served8.322x
10Peu/LitchfieldNashua · 7,000 served8.132x
11Seabrook Water DeptSeabrook · 14,000 served832x
12Hampstead Area WaterAtkinson · 7,153 served7.552x

Highest Lead Levels in New Hampshire

Community water systems in New Hampshire with the highest 90th-percentile lead result under the EPA Lead and Copper Rule. The EPA action level is 15 ppb; there is no safe level of lead for children.

#Water SystemLocationLead 90th-pctile (ppb)vs 15 ppb
1Alton Water WorksAlton · 1,800 served21014.0x over
2Greenville Water DeptGreenville · 1,100 served1107.3x over
3Rollinsford Water Sewer DistRollinsford · 1,688 served432.9x over
4Meredith Water DeptMeredith · 3,750 served422.8x over
5Waterville Estate Vlg Dist/WCampton · 1,250 served372.5x over
6Charlestown Water WorksCharlestown · 2,850 served191.3x over
7Village Dist Of EastmanGrantham · 3,400 served161.1x over
8Newport Water WorksNewport · 5,000 served15within
9Raymond Water DeptRaymond · 3,300 served14within
10Lebanon Water DeptLebanon · 13,600 served12within
11Laconia Water WorksLaconia · 17,000 served11within
12Peterborough Water WorksPeterborough · 4,500 served10within

Most EPA Violations in New Hampshire

Community water systems in New Hampshire with the most health-based EPA Safe Drinking Water Act violations on record. A health-based violation means a contaminant exceeded its federal limit or required treatment was not applied.

#Water SystemLocationHealth-based violations
1Bethlehem Village DistBethlehem · 1,750 served35
2Exeter Water DeptExeter · 12,236 served22
3Contoocook Village PctConcord · 1,600 served22
4Sunapee Water WorksSunapee · 1,680 served8
5Village District Of EidelweissMadison · 1,200 served7
6Enfield Water DeptEnfield · 1,345 served7
7Lincoln Water WorksLincoln · 3,300 served6
8Emerald LakeHillsboro · 1,300 served6
9Rollinsford Water Sewer DistRollinsford · 1,688 served4
10Waterville Estate Vlg Dist/WCampton · 1,250 served3
11Rochester Water DeptRochester · 25,000 served3
12Meredith Water DeptMeredith · 3,750 served3

How This Report Card Is Built

PFAS rankings use EPA UCMR5 monitoring (2023-2025), showing each system's peak detection above the 4 ppt EPA limit. Lead rankings use the EPA Lead and Copper Rule 90th-percentile tap results. Violation counts come from the EPA Safe Drinking Water Information System (SDWIS) and count health-based violations. Lead and violation lists are limited to community water systems serving 1,000 or more people. Figures are the most severe on record and do not necessarily reflect current treated water.

Frequently Asked Questions

What is the most PFAS-contaminated water system in New Hampshire?

In EPA UCMR5 testing (2023-2025), Central Hooksett Water Pct in Hooksett had the highest recorded PFAS level in New Hampshire at 28 ppt - about 7x the EPA's 4 ppt limit for PFOA and PFOS.

Which New Hampshire water system has the highest lead levels?

Alton Water Works in Alton had the highest 90th-percentile lead result in New Hampshire under the EPA Lead and Copper Rule at 210 ppb - 14.0x the 15 ppb action level.

Which New Hampshire water system has the most EPA violations?

Bethlehem Village Dist in Bethlehem has the most health-based EPA Safe Drinking Water Act violations on record in New Hampshire, with 35 violations.

Where does the New Hampshire water report card data come from?

PFAS figures come from EPA UCMR5 monitoring (2023-2025), lead from the EPA Lead and Copper Rule 90th-percentile tap results, and violations from EPA SDWIS health-based violation records. Figures are the most severe on record and do not necessarily reflect current treated water. Check your exact address at knowyourexposure.com.

What New Hampshire Residents Should Do

  1. Look up your exact address at knowyourexposure.com for your system's data
  2. See the full New Hampshire water quality overview
  3. If your system is listed, a certified filter (reverse osmosis for PFAS, NSF-53 for lead) reduces exposure at the tap. See the best water filters.