Town of Nantucket: Easy Street Flood Mitigation Project is Not so Easy

To: Bluedot Living
From: Leah Hill, Coastal Resilience Coordinator, the Town of Nantucket 
Subject: Easy Street Flood Mitigation Project is Not so Easy

When the Town’s Coastal Resilience Plan (CRP) was completed in 2021, the Coastal Resilience Advisory Committee determined the Downtown Neighborhood Flood Barrier – Initial Phase (aka Easy Street Flood Mitigation Project) was the highest priority project due to its criticality and flood vulnerability. Today, this important roadway floods pretty regularly from stormwater (rain), coastal storms, and sea level rise (i.e. sunny day flooding). In fact, in November of 2024, due to sunny day flooding, Easy Street was closed for four consecutive days during high tide. Based on the Massachusetts Coast Flood Risk Model, Easy Street and lower Broad Street could experience daily flooding as soon as 2030. That’s in five years! This has major implications for transportation to and from the Steamship Authority. Not only will this impact people arriving on or departing from the island but will negatively impact the whole island because most, if not all, of our goods and services rely solely on the Steamship.  

The overall goal of the project is to reduce disruptive flooding today and in the future. But to be very clear, it will not reduce all flood risk into the future with sea level rise because it is not feasible to design for every storm event. During certain storms, water may still be on Easy Street. This portion of the project is funded by an Office of Coastal Zone Management grant for a little under $500,000 to develop designs and solicit feedback from the community. The three design options take into consideration all of the project’s goals, independently isolate the project area from flank flooding, will require a stormwater pump station, and have a design horizon to at least 2070. The first design option, bulkhead expansion and elevation, would replace the current bulkheads with a floodwall that is about one and a half feet higher and have “speed humps” on Easy Street, lower Broad Street, and South Water Street. The next two designs are very similar but the Adaptable Road Raising elevates all of Easy Street, lower Broad Street, and all of the adjacent roadways with the ability to increase the road height in the future. This option would be about four feet higher than the existing lowest part of Easy Street located at the Easy Street Oak Street intersection. The last option is to raise the road about five and a half feet from the existing lowest part of Easy Street located at the Easy Street Oak Street intersection. Road raising isn’t as simple as it may seem. All of the driveway connections need to be worked out, utilities within the roadway may need to be elevated, it creates pockets for stormwater to collect, and structures that are not elevated will be below the new road grade. The road raising options will protect this roadway from future groundwater rise and the bulkhead expansion will not. 

This is the first structural CRP recommendation being implemented and we are well aware that it is the first step of a long journey. No matter which design option is chosen, it is going to be a major undertaking, large-scale, expensive, and require an appetite for transformation. There have been multiple meetings about this project at the Select Board, Coastal Resilience Advisory Committee, stakeholders, abutters and the community. For more information, please visit the project’s webpage.