By Seth Daniel
Often times, when tides rise to new highs or storm surges inundate typically dry areas, communities learn anew about their vulnerability to flooding and, potentially, sea level rise.
Through using heavy data and months of study, the City has identified that the Sullivan Square area – especially Ryan Playground, the Main Street/Bunker Hill Street intersection and the Schrafft’s Center properties – is one of nine spots citywide where action is going to be taken soon to prevent major flooding problems.
The area was identified in the Climate Ready Boston report, which was revealed in December. However, a short-term plan to relieve potential problems was just unveiled within the Sullivan Square planning effort.
“As part of the Climate Ready Boston report, we identified nine spots in four of five neighborhoods where flood pathways exist,” Mia Goldwasser, climate preparedness manager for the Boston Environmental Department. “One spot was in Charlestown right in and around the Sullivan Square area. This hot spot is on the infrastructure near Ryan Playground and the Schrafft’s properties. We decided to work first on the Charlestown spot and two spots on the waterfront in East Boston. These pathways are pretty narrow and specific and where a solution could be determined somewhat easily.”
Goldwasser said a design team has been working on the Charlestown site, along with the two Eastie sites, and has come up with a solution that will protect the Neck from serious flooding problems through 2030 due to sea level rise and/or storm surge flooding. The solution was based upon hydrological models produced by MassDOT during the Big Dig, numbers that were used to inform the Climate Ready Boston report and are seen as the gold standard in planning for flood protection throughout Greater Boston.
The solution, she said, is to raise and elevate the roadway along Main Street from approximately the Gardens to Sullivan Square by two feet. If they raise it higher, they can provide flood protection for more years beyond 2030.
The idea is that by raising the elevation of the road, it would block any storm surge coming from the Mystic River via Ryan Playground and the Schrafft’s Center property. That would prevent floodwater inundation into the Main Street and Sullivan Square areas.
Right now, the street dips down very low as it approaches Sullivan Square, making a natural valley for water to flow if it overcame the seawalls along the Mystic River.
The Climate Ready Boston study and the new solution had the benefit of hitting the streets at the same time as the Rutherford Avenue Planning Process began to wrap up its preferred design. With that synchronicity came the alignment of the two goals, which allowed the flood protection project on Main Street and the Neck to be included in the long-term plan for Sullivan Square.
A longer-term objective in partnership with the City, the Flatley Company (Schrafft’s) and the MBTA is to raise the seawall several feet along the edge of the property going all the way to the Amelia Earhart Dam on the Somerville border.
“This was really the right point in time where the planning process and this effort came together at the same time,” she said.
Climate Ready Boston kicked off in 2015 with a Scientific Advisory Board meeting at UMass Boston to begin the discussion of creating flood protections for Greater Boston from sea level rise and from abnormal storm surges.
That study looked at the hydrological numbers from MassDOT, identified the nine hot spots and made recommendations for preparing for sea level rise, storm surge, building techniques, higher temperatures and other such events.
That report published in December 2016, and is now used to inform projects, development and infrastructure needs throughout the city.