The Wellington Underpass project will create a safer, more accessible connection for pedestrians and cyclists while closing a key gap in the Mystic River Greenway. Once complete, the shared-use path will link Torbert MacDonald State Park, Station Landing/Wellington Massachusetts Bay Transportation Authority (MBTA) Station, and the Wellington Greenway, improving mobility, recreation, and community access along the Mystic River.
Nitsch Engineering is providing land surveying, structural engineering, transportation engineering, hydraulic modeling, and environmental permitting services for the project. The design includes a timber boardwalk beneath the Fellsway Bridge (Route 28) along the north bank of the Mystic River, creating a safe and Americans with Disabilities Act (ADA)-compliant route through a previously inaccessible section of the corridor.
To support design development, Nitsch conducted a detailed survey of the project area to document existing topography, property lines, utilities, and rights-of-way. Using this information, our team established the path alignment, established the underpass plan and profile in compliance with ADA standards, determined the limits of the proposed boardwalk along the Mystic River, and designed the boardwalk approaches on the riverbank and connections to existing walkways and bike lanes along Route 28.
Nitsch also designed the timber boardwalk structure, which consists of a certified IPE timber deck supported by timber joists and beams, helical piles, and two abutments with shallow foundations. Throughout preliminary design, we worked closely with the Mystic River Watershed Association (MyRWA), the City of Medford, and other stakeholders to build consensus around the project vision and design approach.
Because the proposed structure is located within a Federal Emergency Management Agency (FEMA)-regulated floodway, Nitsch developed a hydraulic model to represent the flow below the proposed underpass. Using the FEMA Hydrologic Engineering Center’s River Analysis System (HEC-RAS) model of the Mystic River basin as the base, we modified the model to incorporate the proposed piers and deck of the underpass; the results demonstrated that the project would not reduce flood storage capacity or increase water surface elevation of the Mystic River. We submitted a No-Rise Certification to the City of Medford.
Nitsch guided the project through a complex permitting process, evaluating impacts to environmental resources and Environmental Justice populations and coordinating approvals with the City of Medford, Massachusetts Department of Transportation (MassDOT), Department of Conservation and Recreation (DCR), and MyRWA. Our team prepared and supported permitting efforts under the Wetlands Protection Act, US Army Corps of Engineers’ Chapter 91, and Massachusetts Environmental Policy Act (MEPA).
The project is currently under construction and is anticipated to be completed in spring 2028.
Key Collaborators
Owner: City of Medford in collaboration with MassDOT, Department of Conservation and Recreation, and Mystic River Watershed Association
Landscape Architect: Copley Wolff Design Group
Environmental Consulting: LEC Environmental Consultants
