The Monsignor William J. Casey Overpass is the elevated section of Route 203 which carries the Arborway over Washington and South Street in the Jamaica Plain neighborhood of the City of Boston. The Overpass is located directly north of the Forest Hills Station. (See locus map). The area around the overpass serves many neighborhoods and traveling consistencies including pedestrians, cyclists, MBTA riders and motorists. The area also acts as an important gateway to such Boston institutions as Franklin Park, Forest Hills Cemetery, Shattuck Hospital and the Arnold Arboretum. In 2010, the overpass was determined to be structurally deficient, suffering from numerous superstructure and substructure problems due to a combination of deterioration and original design flaws and beyond the point of effective repair.
This project consists of removing the existing structurally deficient 1,650’ Casey Overpass and replacing it with a simplified at-grade reconstructed roadway network. A new fully accessible Orange Line access/egress headhouse will replace the existing substandard exit only headhouse. Bicycle and pedestrian accommodations will be enhanced throughout the project limits. The Route 39 bus will be relocated to the reconstructed upper busway at Forest Hills Station. The project will result in the reconnection of the Arborway and Emerald Necklace Park from the Arnold Arboretum to Franklin Park.
The streetscape has been designed with permeable pavers along sidewalks and bike paths. The runoff of water into these pavers will help to water the trees planted within the permeable paver areas. Existing granite block and cobblestone are being reclaimed from the project area for use in the proposed medians and short retaining walls. There is a net increase of approximately 560 trees. These proposed trees will contribute to the reconnected Emerald Necklace Park and Arborway. The project area contains four larger plaza areas: Toole Square, Southwest Corridor Park Plaza, MBTA North Plaza, and Shea Square Plaza. Each of these areas has unique aspects.
- Toole square has been redesigned as a passive park, with winding paths.
- Southwest Corridor Park Plaza creates a grander entrance to Southwest Corridor Park, with an innovative bicycle roundabout to direct bicycles and pedestrians through the entrance and an “urban park” of trees.
- The MBTA Forest Hills Station North Plaza has been designed to provide clear paths for MBTA patrons while opening the plaza to possible other uses, such as farmers’ markets.
- Shea Square replaces the existing Shea Circle, providing historical information about the old circle, Franklin Park and Morton Street, while creating a small resting area and park where the travel lanes of the rotary currently are.
The Upper Busway of the Forest Hills MBTA Station is designed to minimize light pollution to neighboring communities, with short walls placed to block headlights from hitting the houses without impeding views, and a landscaped buffer area along the Busway to provide separation.
View historical information on the Design/Planning process for the Casey Arborway Project on the Project Overview page.