Harbors & Water Quality

The Commonwealth is reviewing the Town’s updated Nantucket and Madaket Harbors Action Plan. Written public comments are due by 5 p.m. on Friday, September 25, 2026.

Nantucket Tipping Point has submitted comments supporting approval, provided the state’s decision addresses two issues:

1. Bring the water-quality record through 2025, explain the remaining margin against nitrogen-restoration targets, establish clear responses to exceedances, and provide for continued PFAS monitoring and appropriate public-health review.
2. Expressly confirm that the existing harbor licensing protections remain in effect.

The Town detected PFAS at 13 of 21 surface-water sites across Nantucket. Its study included sampling in both the Nantucket and Madaket Harbor areas, and PFAS was found at much higher concentrations in foam collected at Madaket Harbor and Sesachacha Pond.

All measured surface-water concentrations were below the state’s 20 ng/L bathing-water guidance value for the eight covered PFAS. That is reassuring for recreational contact, but it does not fully address sources, groundwater movement, sediment, ecological effects, accumulation in fish and shellfish, or long-term exposure through several pathways.

NTP is not claiming that PFAS has caused cancer on Nantucket or that a cancer cluster has been established. We have asked MassDPH to review Massachusetts Cancer Registry data for Nantucket and determine whether further research, exposure assessment, or pilot biomonitoring is warranted.

The plan should set clear limits on nitrogen, wastewater, PFAS, boating, and development to protect the ecological health and capacity of Nantucket and Madaket Harbors.

Read the Plan

Nantucket and Madaket Harbors Action Plan

Submit a Comment

Email Stephen McKenna at stephen.mckenna@mass.gov by 5 p.m. Friday, September 25, 2026.

Comments do not need to be lengthy. Read the materials, decide which issues matter to you, and write in your own words.

Read NTP’s Submitted Comment Below