For decades after its construction in the 1960s, locals had a wry nickname for Boston City Hall Plaza—“the red tundra,” for its wide, treeless, wind-swept expanse of red brick. Some celebrated it for its boldly democratic vision to create a grand public square for the city’s civic center. Its angled terraces were inspired by the historic plazas of medieval Europe, and its red brick was an extension of the colonial-era streets of downtown Boston. But even many of the plaza’s defenders admitted that its vast size and imposing terraces often intimidated the very public they were meant to welcome.
After years of such debate, the city began asking how it could turn a five-acre (2 ha) plaza of stepped brick and granite into an inviting destination for all.
A newly renovated and reopened Boston City Hall Plaza has finally provided an answer. The city of Boston embarked on a bold new vision for the plaza, and Sasaki—the lead designer—transformed the historic site into a welcoming outdoor place focused on adaptability, accessibility, and sustainability. And this vision included trees—lots of them.
Creating Adaptable Spaces
Despite the criticism, the plaza nonetheless held a special place in the city’s consciousness as the site of countless concerts, rallies, and festivals. It was clear from early public engagement, which formally began in 2015, that a new plaza should still accommodate these sorts of large civic and cultural events. But for the majority of the time when the old plaza was not hosting a festival, its sheer breadth discouraged people from using it for smaller events, or even as a place to stop and linger between other destinations.
One major goal for the renovation was to make Boston City Hall Plaza more adaptable to a wider variety of everyday uses, including festivals, farmers markets, marches, or just meeting friends for lunch. Sasaki accomplished this by subdividing the plaza’s wide expanse of brick into a collage of smaller program areas that remain fluidly connected to retain capacity for large-scale events.
In addition to preserving a large central gathering area directly in front of City Hall—the Main Plaza, with enough capacity to hold 15,000 people on its own—Sasaki used planters of trees and native plants to demarcate permeable side spaces better suited to hosting smaller events. These spaces are all linked through a continuous sloping walkway that weaves across the entire plaza.
The plaza’s grand reopening in November 2022 demonstrated just how flexible these spaces could be. The plaza circle, just off the main plaza, served as an amphitheater for a local steel drum ensemble on the day of the event. The Hanover entrance steps, tucked in under a corner of City Hall’s monumental concrete eaves, became a stage for a high school jazz band. A choir sang to a crowd of onlookers from the rooftop terrace of a new civic pavilion. This new community building provides flexible indoor space on the plaza and offers public restrooms and a meeting space for up to 150 people.
But perhaps the most popular design intervention has been the new plaza playscape. The 12,000-square-foot (1,100 sq m) playground is accessible to all children and features active play, sensory play, and water play for a range of ages and abilities. It was designed to mirror City Hall’s architecture, with a style the design team dubbed “Kinder Brutalism” in honor of the iconic edifice. It features “falling cube” playground elements that mimic the bold shapes of City Hall itself, reflecting the materials of the building and the plaza. And it is crowned, quite literally, by an impressively long slide that has enticed children and elected officials alike.
Combined, all these new auxiliary spaces can still host a total of 20,000-plus people. But with its new adaptability, Boston City Hall Plaza has taken on an entirely different sort of character. The “red tundra” was a place to pass through briskly in warm weather, avoid altogether in windy weather, and visit only for massive public events. Now, it is a daily destination in its own right that welcomes all people with spaces that accommodate a multitude of uses.
Accessibility
Another imposing feature of the old plaza’s design was its sheer inaccessibility. The site spans a 26-foot (8 m) vertical drop between Cambridge and Congress streets, and to navigate that elevation change, the old plaza employed a long series of granite steps. Leading up from Congress Street, these steps created a virtual mountain of stairs and offered no code-compliant accessible alternate route. The degraded brick pavement on the old plaza also posed significant challenges to accessibility. Many surfaces were heaved, chipped, or disjointed, creating a vast space riddled with impediments. Boston City Hall Plaza was a five-acre (2 ha) mobility barrier, impeding access to the center of downtown Boston and to City Hall itself.
Despite this barrier to their seat of government, disability advocates pushed universal accessibility to the forefront of the city’s plaza renovation priorities. As defined by Kristen McCosh, Boston’s disability commissioner, herself a longtime advocate, universal accessibility means ensuring that equal access is integrated into and across a design, not just tacked on in the form of a winding ramp off to one side.
To achieve that vision, Sasaki transformed a highly stepped terrain into a series of gradually sloping surfaces, all spatially unified by a central promenade called “Hanover Walk.” The firm also provided universal access to City Hall itself by replacing the main entrance steps and its old asphalt ramp with a gradual incline, and by reopening an entrance on the opposite side of the building that had been closed since the terrorist attacks of September 11, 2001.
These changes, however, were complicated by a monumental engineering challenge. Some of the country’s oldest operating subway tunnels run directly underneath City Hall Plaza. Sasaki had to work closely with the Massachusetts Bay Transit Authority (MBTA), its technical consultants, and the Shawmut construction team to flatten the plaza’s terrain and build accessible walkways on top of these tunnels. Doing this construction safely without interrupting regular subway service required unearthing the existing tunnels, structurally reinforcing them, and then covering them back over with specially designed lightweight fill, before finally adding on the surface materials and tree planters visible today.
Sustainability
Boston is one of the oldest port cities in the United States, and its aging infrastructure is especially vulnerable to climate change and rising sea levels. Several recent “100-year storms” have flooded downtown and brought tides up above street level, well within sight of City Hall. As Boston finalizes a climate action plan focused on coastal resilience strategies, sustainable design became another critical goal for the renovation of City Hall Plaza.
The old plaza consisted almost entirely of hard, impermeable surfaces that prevented the ground from absorbing rain and discharging it at a steady rate. The resulting urban runoff from the plaza exacerbated downstream flooding and washed surface pollutants into the Boston Harbor.
City Hall Plaza’s new design inverts this dynamic. Sixty percent of its surface is either porous plant beds or made of permeable materials, meaning it can absorb up to 180,000 gallons (681,000 liters) in a single rainstorm, filtering it back into the groundwater system and avoiding downstream impacts. This rainwater is collected, treated by a stormwater filtration system, and then either cycled cleanly back into the groundwater system or stored in a 10,000-gallon (37,900 liters) underground tank. These measures ensure that Boston City Hall Plaza will be an asset for flood management rather than a liability.
The rainwater collected in the underground storage tank is also used to irrigate all the new planting areas across the entire plaza, eliminating the need to use municipal water. A public space long notorious for its lack of greenery, City Hall Plaza is now shaded and sheltered by 250 new trees, 3,000 new shrubs, and 10,000 new perennials and grasses. Within 10 years, the trees’ canopy will grow to cover 25,000 square feet (2,300 sq m) of the plaza’s surface, mitigating the urban heat island effect while sequestering 55,000 tons (49,900 metric tons) of carbon dioxide.
Besides making downtown Boston a safer and more sustainable place, these systems of green infrastructure make City Hall Plaza a more inviting place for everyday activity. Trees and shrubs give visitors a cool place out of the sun to relax in during the summer and protection from the wind in winter. Informational signage about the underground stormwater system is dispersed throughout the plaza, informing curious minds of all ages about the unseen work that goes into designing resilient built environments. These everyday material benefits help build a transparent case for sustainable design across Boston and beyond.
Bostonians are embracing City Hall’s welcoming new front yard. With its adaptable new venues, its universally accessible design, and its sustainable and forward-thinking engineering, Boston City Hall Plaza has come a long way from its days as a so-called red tundra. Rather than a place to merely pass through with a collar turned up to the wind, or avoid altogether, the plaza has become a destination—a place to come for lunch, a stroll, or a playground meetup.
MAURICIO GOMEZ is senior associate landscape architect for Sasaki and served as project manager for the Boston City Hall Plaza renovation. SHANE WOOLLEY is a communications and public relations coordinator for Sasaki.
