New Hampshire water quality overview
New Hampshire's drinking water quality is fair overall, with an average score of 64.9 out of 100 across 98 cities tested. The median score is 66.7, serving a total population of 769,775 residents. 32% of cities scored a D or F, pointing to significant water quality challenges in parts of the state. PFAS "forever chemicals" were detected in 20 of 98 cities tested (20%). 14 cities exceed the 2024 EPA maximum contaminant levels. 45 cities have lead levels exceeding the EPA action level of 15 ppb, often indicating aging infrastructure with lead service lines or lead solder. The state relies on a mix of water sources: 58 cities use groundwater while 40 draw from surface water such as rivers, lakes, and reservoirs.
Issues to watch in New Hampshire
Explore contaminants in New Hampshire
More contaminants tested in New Hampshire
Private-well water in New Hampshire
Based on USGS Powell Domestic-Well Database — 629 private wells sampled across New Hampshire. These wells are not regulated by the EPA; if you draw your tap from a private well, the public-system grade above does not apply to you.
Top industrial water polluters in New Hampshire
Industrial polluters nearby
The 10 facilities reporting the most pounds released to surface water in New Hampshire, 2023.
Total reported releases to surface water: 346 lbs
| Facility | Top chemical | To surface water (lbs/yr) |
|---|---|---|
MERRIMACK STATION BOW, NH03304 | Ammonia | 254 |
WATTS REGULATOR CO DBA WEBSTER VALVE FRANKLIN, NH03235 | Copper | 66 |
SPRAGUE RIVER ROAD TERMINAL NEWINGTON, NH03801 | 1,2,4-Trimethylbenzene | 11 |
MARMON UTILITY LLC MILFORD, NH03055 | Copper | 5 |
FREUDENBERG-NOK SEALING TECHNOLOGIES BRISTOL, NH03222 | Zinc compounds | 4 |
+ 3 more facilities
Source: EPA Toxic Release Inventory (TRI) 2023
How New Hampshire cities scored
Best Cities
Worst Cities
Water quality across New Hampshire
Each dot is a city, colored by its water quality grade. Size reflects population served. Click any city to view its full water report.
98 cities in New Hampshire
| # | City | Grade | Score | Population | Violations |
|---|---|---|---|---|---|
| 1 | Litchfield | A | 93.5 | 7K | 1 |
| 2 | Claremont | A | 90.3 | 9K | 44 |
| 3 | Antrim | A- | 89.9 | 920 | 12 |
| 4 | Franklin | A- | 89.8 | 7K | 75 |
| 5 | Somersworth | A- | 89.7 | 12K | 38 |
| 6 | Bristol | A- | 89.7 | 4K | 5 |
| 7 | Keene | A- | 89.2 | 30K | 22 |
| 8 | Hanover | A- | 89.2 | 9K | 50 |
| 9 | Lancaster | A- | 89 | 2K | 44 |
| 10 | Bedford | A- | 88.8 | 3K | 9 |
| 11 | Nashua | A- | 88.7 | 89K | 4 |
| 12 | Boscawen | A- | 88.6 | 4K | 15 |
| 13 | Barnstead | A- | 87.5 | 2K | 74 |
| 14 | Rye | A- | 86.7 | 4K | 6 |
| 15 | Marlborough | A- | 86.7 | 850 | 75 |
| 16 | Unity | A- | 86.4 | 625 | 89 |
| 17 | Littleton | A- | 85.8 | 7K | 77 |
| 18 | Peterborough | A- | 85.3 | 5K | 46 |
| 19 | Hooksett | A- | 85.2 | 8K | 78 |
| 20 | Merrimack | B+ | 84.2 | 26K | 42 |
| 21 | Dover | B+ | 84 | 29K | 58 |
| 22 | Berlin | B+ | 83.3 | 10K | 3 |
| 23 | Whitefield | B+ | 81.9 | 2K | 16 |
| 24 | Grantham | B+ | 81 | 3K | 50 |
| 25 | Lincoln | B+ | 81 | 3K | 17 |
| 26 | Jaffrey | B+ | 80.9 | 4K | 45 |
| 27 | Portsmouth | B+ | 80.7 | 43K | 14 |
| 28 | Newmarket | B | 79.3 | 5K | 239 |
| 29 | Durham | B | 78.8 | 16K | 55 |
| 30 | Farmington | B | 77.5 | 3K | 17 |
| 31 | Epping | B | 76.7 | 2K | 106 |
| 32 | Pembroke | B | 75.8 | 5K | 84 |
| 33 | Hudson | B | 75.4 | 17K | 68 |
| 34 | Wilton | B | 75.2 | 2K | 28 |
| 35 | Henniker | B- | 73.8 | 3K | 70 |
| 36 | Woodstock | B- | 73.8 | 3K | 24 |
| 37 | Lebanon | B- | 72.9 | 10K | 128 |
| 38 | Newfields | B- | 72.7 | 550 | 22 |
| 39 | Troy | B- | 71.5 | 1K | 52 |
| 40 | Hinsdale | B- | 71.2 | 3K | 231 |
| 41 | Newport | B- | 71.1 | 5K | 168 |
| 42 | Hampstead | B- | 71 | 7K | 96 |
| 43 | Gorham | B- | 70.9 | 3K | 64 |
| 44 | Waterville Valley | B- | 70.6 | 3K | 13 |
| 45 | Northumberland | C+ | 69.3 | 3K | 43 |
| 46 | Seabrook | C+ | 68.2 | 14K | 221 |
| 47 | Sunapee | C+ | 67.3 | 2K | 82 |
| 48 | Plainfield | C+ | 66.9 | 750 | 182 |
| 49 | Wolfeboro | C+ | 66.8 | 6K | 129 |
| 50 | New Castle | C+ | 66.7 | 910 | 29 |
| 51 | Pittsfield | C+ | 66.6 | 2K | 124 |
| 52 | Colebrook | C+ | 66.6 | 1K | 69 |
| 53 | Brentwood | C+ | 66.5 | 1K | 7 |
| 54 | New London | C+ | 65.7 | 3K | 110 |
| 55 | Rollinsford | C+ | 65.6 | 2K | 47 |
| 56 | Franconia | C+ | 65.4 | 1K | 120 |
| 57 | Ashland | C+ | 65.3 | 2K | 105 |
| 58 | Lisbon | C | 64.9 | 1K | 65 |
| 59 | Warner | C | 64.7 | 878 | 28 |
| 60 | Plymouth | C | 64.2 | 7K | 255 |
| 61 | Northwood | C | 64.1 | 965 | 118 |
| 62 | Winchester | C- | 59.5 | 3K | 62 |
| 63 | Meredith | C- | 59.4 | 4K | 292 |
| 64 | Allenstown | C- | 59.4 | 800 | 58 |
| 65 | Charlestown | C- | 58.1 | 3K | 217 |
| 66 | Stow | C- | 56.8 | 675 | 284 |
| 67 | Jackson | C- | 55.6 | 570 | 92 |
| 68 | Swanzey | D+ | 54.3 | 666 | 291 |
| 69 | Bethlehem | D+ | 51.8 | 2K | 65 |
| 70 | Concord | D+ | 51.3 | 44K | 63 |
| 71 | Manchester | D+ | 50.9 | 124K | 20 |
| 72 | Wakefield | D+ | 50.1 | 1K | 78 |
| 73 | Greenville | D | 48.9 | 2K | 153 |
| 74 | Walpole | D | 48.7 | 1K | 210 |
| 75 | Haverhill | D | 47.7 | 540 | 246 |
| 76 | Madison | D | 47.6 | 1K | 61 |
| 77 | Salem | D | 47.4 | 21K | 292 |
| 78 | Epsom | D | 47.3 | 2K | 99 |
| 79 | Alton | D | 46.1 | 2K | 214 |
| 80 | Goffstown | D | 45.9 | 4K | 61 |
| 81 | Hillsborough | D | 45.9 | 2K | 224 |
| 82 | Bartlett | F | 44.1 | 854 | 555 |
| 83 | Milford | F | 43 | 10K | 195 |
| 84 | Conway | F | 42.8 | 3K | 597 |
| 85 | Rochester | F | 42.5 | 26K | 317 |
| 86 | Derry | F | 42.5 | 18K | 390 |
| 87 | Raymond | F | 40.2 | 4K | 154 |
| 88 | Canaan | F | 40.1 | 984 | 121 |
| 89 | Andover | F | 39.9 | 650 | 89 |
| 90 | Exeter | F | 37.5 | 14K | 203 |
| 91 | Enfield | F | 33.2 | 1K | 211 |
| 92 | Gilford | F | 31 | 3K | 1030 |
| 93 | Barrington | F | 31 | 803 | 619 |
| 94 | Campton | F | 30 | 2K | 532 |
| 95 | Belmont | F | 30 | 2K | 444 |
| 96 | Loudon | F | 28 | 808 | 374 |
| 97 | New Hampton | F | 28 | 600 | 133 |
| 98 | Moultonborough | F | 27 | 3K | 627 |
Browse New Hampshire by ZIP code
Look up water quality by ZIP code to find the systems serving your area.
View all New Hampshire ZIP codes →Frequently asked questions about New Hampshire's water
Is New Hampshire's tap water safe to drink?
New Hampshire's water quality varies by city. The statewide average grade is C (64.9/100). 45% of cities scored an A or B, while 32% received a D or F. Check your specific city for detailed results.
Which New Hampshire cities have the best water quality?
The top-rated cities are Litchfield (A), Claremont (A), Antrim (A-). These cities scored highest based on violation history, lead levels, PFAS contamination, and regulatory compliance.
Which New Hampshire cities have the worst water quality?
The lowest-rated cities are Moultonborough (F), New Hampton (F), Loudon (F). We recommend residents in these areas consider water filtration and review their city's specific contaminant data.
How many New Hampshire cities have PFAS in their water?
20 out of 98 cities tested positive for PFAS "forever chemicals" (20%). 14 cities exceed the 2024 EPA maximum contaminant levels. Reverse osmosis or activated carbon filters can help reduce PFAS exposure.
Do any New Hampshire cities have dangerous lead levels?
45 cities exceed the EPA lead action level of 15 ppb. Lead contamination typically comes from aging pipes and lead service lines rather than the water source itself. An NSF 53-certified filter can effectively remove lead from tap water.