FROM THE TOWN OF NANTUCKET NEWSLETTER
At the June 11, 2021, Nantucket Historic District Commission meeting, Resilient Nantucket: Flooding Adaptation & Building Elevation Design Guidelines were unanimously adopted (4-0) by the Commission. Nantucket Island is one of the nation’s largest National Historic Landmark Districts with over 1,000 pre-1860s structures contributing to its historical, architectural, and cultural significance. And yet, these irreplaceable resources are increasingly threatened by short- and long-term flooding caused by sea-level rise. Resilient Nantucket not only provides suggested practices for the built environment, but it also addresses several priority actions identified in the Town’s Municipal Vulnerability Program (MVP) Community Resilience Workshop Report (2019) and the Hazard Mitigation Plan (2019.)
These guidelines include suggested practices for flooding adaptation and building elevation design details for Nantucket’s buildings and streetscapes at risk of flooding and sea-level rise. The Resilient Nantucket addendum follows the recommendations and “best practices” for resiliency and flood mitigation strategies for historic buildings, as outlined by the National Park Service’s Standards on Flood Adaptation for Rehabilitating Historic Buildings published in 2019 and illustrated in 2021.
Properties that are 50 years old or older and which retain their architectural and historical integrity are considered contributing to the character of the Nantucket National Historic Landmark District are considered historic buildings/structures.
For contributing properties at risk of flooding, treatments should be undertaken to avoid or minimize the impacts and to ensure the continued preservation of the property in its historic character. If a contributing structure in Nantucket’s floodplain undergoes substantial improvement (under the Building Code) or damage (worth 50% or more of the structure’s market value), the structure must be brought up to code. However, the definition of substantial improvement exempts “any alternation of a historic structure, provided that the alteration will not preclude the continued designation as a historic structure.[1]” This exemption can be interpreted as an exemption only from those flood mitigation activities that would preclude the structure’s historic designation (as recommended by the National Park Service.)
Funding for Resilient Nantucket was made possible from the Massachusetts Executive Office of Energy and Environmental Affairs Municipal Vulnerability Preparedness (MVP) Action Grant Program and the project was conducted by Thomason & Associates and The Craig Group.
Any questions on the Resilient Nantucket document, please contact the Town’s Preservation Planner at hbackus@nantucket-ma.gov.