Coastal, River, & Wetland Restoration
Sustainable Design Consultant for:- Hearthstone Quarry Brook Riparian Restoration Project
Design, Construction Oversight & Monitoring
the challengeDue to heavy stormwater runoff from its urban surroundings, the Hearthstone Quarry Brook in Chicopee, MA suffered from severe erosion and channel incision. The brook runs through dense residential area and receives stormwater runoff from area roads, highways, homes, and parking lots. When a planned road expansion caused even more stormwater flow to the brook, the City of Chicopee recognized that this additional flow would aggravate the existing problems of severe channel incision, erosion, and loss of wetland resources and represented a threat to both infrastructure (a main road and a sewer siphon) and private property due to ongoing stream instability. Constraints included a narrow construction access corridor, presence of regulated resource areas, extremely steep and hazardous banks, and the need to gain permission from numerous private landowners to perform stream stabilization work.
the interdisciplinary approach The Bioengineering Group led the planning of the project by identifying the causes of the instability problems, devising solutions to systematically address the problems, and assisting the city of Chicopee in securing an EPA s. 319 grant. Working in collaboration with municipal and state personnel, as well as the city’s engineering team, our staff performed design, permitting, and construction phase services, and to use bioengineering techniques to stabilize a geomorphically restored channel, abate non-point source pollution, and enhance the brook habitat. After conducting a channel assessment, gathering field data, and using HEC2 modeling, the team established the final design for the project. In order to account for the site’s steep banks and dense tree canopy, shade-tolerant vegetation selection was critical. Our staff integrated vegetation into gabion structures, which were designed to maintain proper channel dimensions as well as gradient and riparian functions, and, where practical, employed low cost natural log structures to provide further grade control and aquatic habitat. Due to limited access outlets, the confined incised valley, adjacent residential property, and saturated clay soils, we had to closely supervise construction and make on-site modifications to the engineering designs. A later phase addressed upstream detention and infiltration of stormwater captured from the Mass Turnpike to abate peak flows. Furthermore, our staff designed a monitoring scheme to assess and document pre-and post-construction channel stability, habitat values, and vegetation performance.
the resultsThe project received one of the largest EPA grants in the state’s 319 grant program history, won a regional ACEC award, and is recognized for increasing property values of the adjoining corridor. The monitoring protocol documented clear and specific habitat and water quality benefits from the project, and the protocol itself has become the standard used within the state for similar projects. The project represents a successful collaboration between two state transportation agencies, a municipality, and private landowners, with additional state and federal funding, and has helped build recognition and support for an increasing amount of related work throughout the decade since its successful completion. Several technical articles have been published about the project design approach and monitoring results, contributing much-needed peer-reviewed documentation in this rapidly evolving field.