Olmsted’s Emerald Necklace: Opportunities To Expand Non-Motorized Transportation in Boston

by Phil Goff, Planner, Alta Planning + Design

Frederick Law Olmsted’s Emerald Necklace is Boston’s late-19th century gem that helped open the design/engineering profession’s eyes to the ability of well-designed landscapes to tie together parts of the city with a network of green spaces, boulevards, parks and carriageways. Like Central Park and others, it was also a master work of civil engineering as Olmsted’s team channelized the Muddy River floodway into a beautiful man-made riparian corridor. The Emerald Necklace struggles to live up to this pedigree however, as it has been whittled away for decades by automobile infrastructure that removed green space, severed connections to nearby communities and compromised walking and bicycling.

Emerald Necklace.

Help is on the way. Due to the combined efforts of the Massachusetts Department of Conservation and Recreation (DCR), Massachusetts DOT (MassDOT), the City of Boston and the Town of Brookline, a number of new initiatives and projects have either begun or are on the drawing board. While the automobile will continue to be a significant presence along the Necklace, the various projects will increase greenspace and improve non-motorized transportation and recreation. This was the subject of the opening day plenary session at the ITE National meeting in Boston this summer. Speakers for the session included Margaret Dyson from the City of Boston, Julie Crockford from the Emerald Necklace Conservancy and Phil Goff from Alta Planning + Design’s Boston office.

Starting in the 1940s, a handful of urban expressways were built in Boston to carry the ever-growing numbers of suburbanites wishing to access the city by car. Planners looked at the existing natural corridors and rivers to build new highways and expressways. Fortunately, a few of the largest and most destructive interstates — the SW Corridor through the South End and Roxbury for example — were stopped by community protests. Others were built however, including the Bowker Overpass at the north end of the Emerald Necklace and the Casey Overpass at the south end. Both featured multi-lane highways elevated high above their adjacent neighborhoods with on and off ramps that dumped thousands of cars onto the adjacent surface streets. The meandering parkway paralleling the Emerald Necklace became a four-lane road with cars traveling 40–50 mph.

The Bowker collected traffic to/from the parkway and other local streets and provided the seamless connection to Storrow Drive, the expressway running along the Charles River. The overpass’s size and clumsy design severed the connection between the Back Bay Fens — one of the Olmsted parks along the Emerald Necklace — and the Charles River Basin, Charles Elliot’s grand open space developed in stages throughout the first half of the 20th century. Currently, there is no physical connection between the two greenway systems. Within the 21st century context of a re-orientation of cities to nature and promoting Complete Streets and active recreation, the City of Boston, state agencies and advocates have begun to emphasize the importance of a seamless greenway system.

Charlesgate: before and after.

Starting in 2009, Alta, along with Halvorson Design Landscape Architects, developed the Charles River Basin Connectivity Study. Funded by MassDOT, with management support from DCR, the Study creates a long-term blueprint for pedestrian and bicycle connectivity between the river and the many neighborhoods, institutions, transit stations, commercial districts and green spaces that lay adjacent to the eight-mile-long Basin. One of the highest priority projects is a short/mid-term solution to the broken connection between the Basin and the Emerald Necklace (long term plans have looked at replacing the Bowker with surface streets and new open spaces). This can be done by widening sidewalks, enhancing crosswalks and building new paths through the “lost park” between the east and west bound travel lanes of Storrow Drive. Facilitating access for peds and bikes to the river esplanade requires a new traffic signal and crosswalk at the Harvard Bridge. The first phase of the final design work is being funded by the Solomon Foundation with Halvorson providing the park design and Alta providing design support for the intersection improvements and the new traffic signal.

Alta is also working to close another critical gap in pedestrian and bike connectivity: a ¾ mile stretch between Netherlands Road and MA State Route 9 in the Town of Brookline. Currently this portion is a complex obstacle course of missing sidewalks, lack of street crossings, and broken paths that dramatically compromise the Emerald Necklace experience for those walking or bicycling (ADA connections are non-existent as well). The Town funded a master plan for this difficult stretch and has grant money to implement the improvements at the infamous Rt. 9 crossing.

This is where the Necklace is sliced by a six-lane portion of Rt.9 with an on/off ramp at one side making the connection even more difficult. Though a signalized crossing exists <200’ away, most cyclists, runners and walkers instead wait for gaps in traffic and dash across. A cut in the three-foot-wide raised median provides a perilous refuge for those making it only half-way across (which is typical). The redesign by Alta and engineering firm GPI includes narrower travel lanes, a wide crosswalk and wider median (from three to nine feet). Final determination of a new ped-actuated signal is on-going. New geometry for the on/off ramps at the south end will improve safety and connectivity as well, especially with the raised path-crossing to slow cars.

Emerald Necklace Crossing.

Other improvements planned for the ¾ mile stretch include replacing a short portion of one travel lane with a two-way cycletrack, newly paved path segments and a trail-crossing signal. All of these will ultimately be designed in accordance with new pedestrian and bicycle connectivity guidelines developed by the Emerald Necklace Conservancy non-profit and recently adopted by DCR. The Guidelines will be used for numerous projects intended to promote more walking, bicycling, running and skating along one of the premiere greenways in the U.S. Ultimately, one of the greatest testaments to Olmsted’s planning and design will be the extent in which the community and government agencies can restore the Emerald Necklace as an interlinked public green space for people, not just for automobiles.