Boston's historical footprint, diverse building stock, and densely populated neighborhoods call for adherence to resilient design principles in order to help the city and others like it counter the effects of climate change.
Rising sea levels and stronger storms have garnered national attention as some of the more visible effects of climate change. Their increasing frequency is testing the mettle of coastal built environments, requiring architects and building owners to think twice about how they’re integrating resilient design practices. A new report
for the Boston Society of Architects and the Boston Foundation for Architecture, commissioned by the city of Boston and the Boston Green Ribbon Commission—which comprises local industry, civic, and academic leaders helping to fulfill the city’s environmental sustainability goals—highlights best practices for architects and designers working in coastal urban areas. The report was prepared by the environmental analytics firm Linnean Solutions, the environmental research group the Built Environment Coalition, both based in Boston, and the Resilient Design Institute, in Brattleboro, Vt.
Released Aug. 7, the 117-page report titled “Building Resilience in Boston: Best Practices for Climate Change Adaptation and Resilience for Existing Buildings” aims the spotlight at Boston’s population and built environment and, specifically, their vulnerabilities such as variations in the age and construction of the city’s building stock and the populous communities built on infill land and in other low-lying areas (see map below). The report concludes with a list of design strategies to buffer these susceptible zones from the effects of climate change, pulling best practices from New York’s PlaNYC program, launched in 2007 to develop and implement infrastructure changes in the face of New York City’s rising population and climate change, as well as London’s and Toronto’s extensive storm-response strategies. The advice can be an invaluable resource or refresher for architects and designers working in North American coastal metropolitan areas from Vancouver, British Columbia, to Miami.
Boston is a good example of a city whose structural pedigree, population density—it’s the fifth largest metropolitan area in the U.S.—and low-lying geography make it uniquely vulnerable to Mother Nature. Its historical roots are partly to blame. The port town was settled in 1625 on a small peninsula connected to the rest of North America by an isthmus. During the early 19th century, the city began rapidly expanding its land mass through infill. Now covering 48 square miles and hosting a population of 626,000, the city rests 46 feet above sea level with the areas created by landfill—including its Back Bay and South End neighborhoods—among its lowest points.
This overlay of historical and contemporary Boston shows the areas created by infill construction, which began in the early 19th century. The landfill areas are some of the city's lowest elevations. The highest point in the city is Bellevue Hill, which is 330 feet above sea level.
Credit: Boston Green Ribbon Commission
Assembled over the course of nearly four centuries, the assortment of building typologies in the city is both a strength and a weakness, the report’s authors write. More than half of Boston’s building stock is at least a half-century old, with the city boasting the highest proportion of pre-World War II housing among major U.S. cities. Though its commercial structures are a bit newer—more than 25 million square feet of commercial space was added between 1960 and 1998—nearly two-thirds of the commercial building stock pre-dates 1930. The lack of homogeneity requires a multipronged hazard-response strategy, but provides “strength through diversity” against storms, the authors say, since each structural form will respond differently to a disaster. Still, computer models from the National Oceanographic and Atmospheric Administration found that in the case of a Category 3 hurricane, nearly one-third of the city of Boston would be “significantly” flooded by storm surges (see image below).
The city of Boston's vulnerability to storm surges, based on the National Oceanographic and Atmospheric Administration's Sea, Lake, and Overland Surges from Hurricanes (SLOSH) models, which calculate the extent of storm surges in coastal regions.
Credit: Boston Green Ribbon Commission
The report’s authors note: “Understanding the city’s vulnerability to climate change and other hazards, and crafting adaptive responses, means understanding the range of building types in the city, as well as understanding how different building types are distributed around Boston and around Boston’s neighborhoods.”
The study’s recommendations for protecting the built environment from storm-related damage cover topics in site planning, the building envelope, and internal operations. At a project’s site, for example, designers can specify pervious pavements to improve groundwater infiltration and reduce stormwater runoff. Load-path connectors in structural framing can add ductility and wind-load resistance to buildings, while foundation drainage systems can reduce water pressure against below-grade walls and subsequently the risk of infiltration. Installing at least one nonelectric toilet and faucet per bathroom keeps buildings functional during power outages. To protect a company’s vital digital infrastructure, the report recommends designers locate information technology equipment and other utilities above-grade.
While the report doesn’t call for specific, wholesale changes in the way architects design and build, it does highlight the increasing study of climate change’s effects on coastal metropolitan areas and the coming push for stronger, code-mandated implementation of more resilient-design principles.
The report was funded by the Barr Foundation, based in Boston.
Read the full report here.
Image via a Creative Commons license with Flickr user runneralan2004.