29th January, 2019

Structural Recycled Plastic Lumber Provides Complete Solution for Assabet River Rail Trail

The Assabet River Rail Trail in Massachusetts is a multi-use recreational trail that passes through the Marlborough, Hudson, Stow, Maynard and Acton communities. Spanning over 12 miles, this trail not only connects these 5 communities together, it also provides a safe path for pedestrian activities like biking and hiking.  

Built along the Marlborough Branch Railroad, which was active between 1853 and 1980, the now abandoned railroad was converted for pedestrian use in 2016, and as a part of the conversion, 450 feet of boardwalk spanning over wetlands needed to be constructed.

Project Date: 2018

Customer Overview

The Massachusetts DOT works to provide the safest and most reliable transportation systems in the State of Massachusetts, to strengthen both the economy and quality of life. They partner with cities and towns, public agencies and private business sectors, to support the environmental and transportation goals of the Commonwealth. With the conversion of the Assabet River Rail Trail, the MassDOT saw an opportunity to help bring the communities together.


The Assabet River Rail Trail is located in Middlesex County, Massachusetts. A new boardwalk was designed to accommodate activities like hiking and biking. Many components including substructure, top boards and piles were included in the walkway design. Each component had unique performance requirements, and the building material needed to meet each specification.

The piles would be partly submerged in water; rot, mold and degradation are common with traditional wood in wet conditions, so the new material needed to withstand these environments. The substructure needed to support light vehicular traffic and pedestrian traffic, so load-bearing requirements were important for this component. The top boards needed to be aesthetically pleasing and hold up against wear-and-tear from biking, hiking and inline skating activities. Finding a versatile and durable building material that met all requirements was crucial to project success.


FiberForce® structural plastic composite building material solved the design challenge. Structural recycled plastic lumber met the project requirements for all of the trail pathway components. Bedford Technology value engineered the design and was able to reduce the amount of material used, which lowered the cost for the installation.

This product doesn’t rot, mold or degrade when submerged in water, which met the durability requirement for the piles. FiberForce® also provided better structural performance compared to traditional wood for the substructure joist and stringer beams compared to traditional wood. The stone design finish on the deck boards provided non-slip properties that were safe for pedestrians and light-duty vehicular traffic.

Assabet boardwarlk


The MassDOT used FiberForce® which solved all of their project requirements and challenges. The biggest driver for using recycled plastic lumber was that it is a long-term building material that is built to last and doesn’t need to be replaced like traditional treated wood. Structural recycled plastic lumber was the best solution for all components including the piles, substructure and decking because it provides a long-lasting, safe and environmentally-friendly trail for pedestrians and vehicles.

“The Assabet River Rail Trail continues to be updated, with only the Stow section remaining. The environmentally-friendly boardwalk has been a great addition to our communities. Average traffic has been 100+ bikes and walkers per day”, said Tom Kelleher, President of Assabet River Rail Trail.


Looking for The Complete Solution for Your Next Boardwalk Project? Contact us today!