Well Water in Portsmouth Area, New Hampshire
Rockingham / Strafford County · Population ~22,000 (Portsmouth); surrounding towns vary · Aquifer: Glacial Outwash / Bedrock
Hardness: Variable
The Portsmouth area was one of the first places in the nation where military PFAS contamination was discovered. The former Pease Air Force Base (now Pease International Tradeport) used PFAS-containing firefighting foams for decades, contaminating groundwater that serves Portsmouth and surrounding communities including Greenland, Newington, and Rye.
Pease Tradeport PFAS: A National Story
In 2014, PFAS contamination was discovered in the Haven well at Pease International Tradeport, which had served drinking water to thousands of workers and children at an on-site daycare. The well had PFOS levels exceeding 2,000 parts per trillion — orders of magnitude above any safe level.
This discovery was one of the first major military PFAS contamination events identified in the United States. It led to:
- Closure of the Haven well
- A CDC/ATSDR health study of exposed individuals (one of the largest PFAS exposure studies in the US)
- Ongoing monitoring of private wells in surrounding communities
- Increased national awareness of PFAS contamination from military sites
Impact on Surrounding Communities
PFAS contamination from Pease doesn't stop at the tradeport boundary. Groundwater flows outward, and private wells in Greenland, Newington, and Rye have been tested as part of the investigation.
The seacoast area also has potential PFAS sources beyond Pease: other military sites, fire training areas, and industrial facilities. NH DES recommends PFAS testing for all private wells in the seacoast region.
Coastal-Specific Concerns
Beyond PFAS, seacoast wells face unique challenges:
- Saltwater intrusion — coastal wells can draw in salt water if over-pumped, especially during drought
- Arsenic — the bedrock geology still applies. Test for arsenic regardless of your proximity to the coast.
- Radon — granitic bedrock produces radon throughout the seacoast area
What to Do
If you're on a private well in the Portsmouth area, prioritize PFAS testing. Contact NH DES about their PFAS testing program — you may qualify for free testing.
Also test for arsenic, radon, bacteria, nitrates, manganese, chloride (saltwater indicator), hardness, and pH.
Treatment systems are available for all these contaminants, and NH rebates can help with the cost. See our testing guide for lab information.
NH Treatment Rebates: If your well water exceeds any health-based standards, you may be eligible for $5,000-$10,000 in state rebates toward a treatment system. Check your eligibility.
Every well is different. Two wells on the same street can produce completely different water. The data on this page reflects documented conditions in the Portsmouth Area area, but the only way to know what's in your water is to test it.
Sources
- NH DES — Pease Tradeport PFAS Investigation
- CDC/ATSDR — Pease PFAS Exposure Assessment
- USGS — Groundwater Quality in Coastal New Hampshire
- NH DES — Seacoast PFAS Well Testing Program