Washington Pedestrian Bridge – Large Scale Built Design – By: BETA Engineering

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Project Statement:
Listed on the National Register of Historic Places, the Washington Bridge, once a city street connector and interstate highway carrier, is now a preserved landmark and vital link in the region’s growing bike path, pedestrian way and park system. The design and geographical location promote the attraction of thousands of bicycle commuters and recreational users as it supports health, educational and economic growth and sustainability.

Project Narrative:

Role of the landscape architects’ leadership and involvement:
The Landscape Architects’ skills in place making promoted historic, social, economic and environmental awareness and sustainability while ensuring safety, accessibility and constructability. Each year, a Rhode Island ASLA chapter delegation has met with state legislators at the National Chapter’s Advocacy Day in Washington D.C. to ensure their support for transportation, recreation and environmental bills relevant to landscape architecture and land stewardship. The Linear Park would not have been possible if it weren’t for federal transportation funding. The Landscape Architect extended an invitation to the legislators to attend the opening ceremony to see the results of their endorsements. “Investing in improvements to our public parks creates good-paying jobs and makes Rhode Island an even better place to live, work, and raise a family,” said Congressman David Cicilline. “This park will provide a beautiful vantage point to take in our Capital City, and make Providence a safer and healthier place to enjoy the outdoors,” said Senator Sheldon Whitehouse. (See Image 1)

Project location, scope and size:
The 1,800 foot long spandrel arch structure of the Washington Pedestrian Bridge extends from Rhode Island’s Capitol City of Providence, across the Seekonk River to the city of East Providence. Both cities are in Providence County, a diverse urban community with a population of 632,000 (60% of Rhode Island’s total population). In the conceptual phase of the project landscape architectural consultant was added to the project design team to evaluate the conversion of the existing bridge to a separate pedestrian/bikeway structure so that the northern sections of the bridge could be demolished to make way for a new structure that now carries part of the ten lane Interstate 195. The project scope was to preserve and rehabilitate the south side of the historic landmark while transforming the existing narrow access path into a seven foot wide pedestrian walkway with an eleven to twelve foot wide bike path separated by a five foot median. Adjacent to the operator’s house in the middle of the bridge would be a fourteen by forty foot overlook plaza to serve as a stopping point for pedestrians and cyclists. (See Image 2)

Site and context investigation:
The Seekonk River flows into the northern tip of the Narragansett Bay, at the bridge crossing, as it makes its way to the Atlantic Ocean. The bridge is the southern terminus of the Blackstone River Watershed and Blackstone Valley National Heritage Corridor, known for its historic mill buildings and role in the industrial revolution (It became a national park in 2010). The Bridge is centrally located central to all of these features and the RI bikeway system. (See Image 3)

Design program, design philosophy, design intent:
The primary design philosophy was to create a safe, comfortable and healthy environment that offers opportunities for education and the discovery with topics on the history of the bridge structures, the transportation history of the river crossing, the settlements of the east and west banks and the geography and ecology of the area were designed by the Landscape Architect in coordination with an historic consultant. (See Images 4-10)

Materials and installation methods:
The repurposing of granite materials and the design of new granite features to fit in with the restored pieces to make a cohesive whole was the most challenging. Granite pieces from the north side piers were marked and carefully removed during demolition. They were stored and laid out in protected areas where they were measured and inspected for damage and usability. Those chosen were cleaned and restored. The Landscape

Architect participated in the restoration process to assure that the pieces fit into the wall and bastion seat designs and that the repaired areas blended in with the repurposed pieces. (See Images 11-14)

Environmental impact and concerns:
Concerns with the Washington Bridge Bike Path project stemmed from demolition equipment and material creating large amounts of debris, contaminants, and erosion along both banks of the Seekonk River. Throughout the permitting process, the design team worked with the RI Department of Transportation to develop an action plan for how to situate demolition equipment, where to store and transfer demolition debris, and how to identify and store reusable materials to be used in the repurposed areas of the Washington Bridge. The Landscape Architects from the design team would later use the saved pieces to highlight unique characteristics of this historic bridge such as the bastion seats. The Landscape Architect also worked with the University of Rhode Island, RI Coastal Resource Management and the Rhode Island Department of Transportation to devise a rooftop planter system using native groundcover materials. During Value Engineering the system was replaced by ornamental grasses requiring minimal maintenance and a self-watering storage tank system within the planters.

Collaboration with the client and other designers, client program, other significant issues:
The design team consisted of a consulting engineer firm, architect and landscape architect. The design went through a process of submissions and review by the various state agencies. The team collaborated on the detailing of the bronze and granite elements and worked to resolve paving material issues. Stone pavers were originally planned for the median and pedestrian way but the weight, cost and constructability became prohibitive. The landscape architect and engineer worked on a solution to use color and stamping on the actual concrete decking that would recall historic materials used on the 1875 Washington Bridge.

Local Significance:
“This project was always about more than just rebuilding a bike path,” RIDOT Director Peter Alviti Jr. said. “The Washington Bridge is part of our collective history, and with the opening of the new Linear Park, we are positioning it to play an important role in our future as well. In addition to restoring a vital connection for bike and pedestrian commuters, it will support development in the area while also celebrating the rich history of this bridge and its neighboring communities. In short order, the new park is sure to emerge as one of our state’s crown jewels.” The recognition by this public official of the successful Washington Pedestrian Bridge project sheds a pleasant light on the public’s understanding of the design profession, stewardship responsibilities and the relationship of the built environment to its context and surroundings.

Special Features:
This project is a unique example of finding a creative and sustainable solution to a transportation problem that positively affects all users. A park and interstate highway are two very conflicting uses, yet the design is able to soften the conflict by allowing a space between the highway and pedestrian bridge along with screen walls and fencing as buffers. Special features add layers of detail that gives the park its own unique character. One such detail is an etched black granite dedication plaque, imbedded on each entrance pylon that names the Linear Park after George Redman, the East Providence resident who was instrumental in the development of the adjoining East Bay Bike Path. (See Image 15) of local history. This is achieved in the overlook plaza, an area with granite screening walls and planters to buffer the highway noise and pollution. Here one can enjoy vistas, restored architectural features and interpretive elements that were called for in the design program. The materials and furnishings chosen by the Landscape Architects were intended to embrace the historic character, exemplified by the ornamental lighting that is similar to the original bridge lights, the custom bike racks, seating, bollards and chain, to the granite signage pylons with a memorial plaque that mark entry and a bridge plaque granite stand. As an educational enhancement four interpretive panels.

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