CONWAY — Residents stopped by Town Hall this week to get an inside look at the town’s efforts to prevent and prepare for future flooding.
Rosalie Starvish, a senior project manager and water resources engineer with GZA GeoEnvironmental Inc., and Nicolas Miller, a fluvial geomorphologist with Field Geology Services, have been looking into changes to the South River watershed that could reduce flooding in the town center as part of a Municipal Vulnerability Preparedness (MVP) grant, a program that aims to help communities build climate resilience.
“We’re taking this holistic approach driven by the science of fluvial geomorphology,” Miller said to preface Tuesday’s information session.
According to the University of Massachusetts Amherst’s Center for Agriculture, Food and the Environment, “Fluvial geomorphology is the study of the interactions between the physical shapes of rivers, their water and sediment transport processes, and the landforms they create” that focuses on the movement and evolution of rivers.
“We realize part of Shelburne Falls Road washes out, but the problem is larger than that,” Miller explained. “Why is Shelburne Falls Road washing out? What can we do to prevent that sort of thing from happening as frequently?”
By analyzing the topography of the South River, Miller and Starvish created designs for lowering the South River floodplain by removing 40,000 cubic yards of “legacy sediment” from a section of the river north of Eldridge Road and east of Route 116 by the former Tucker & Cook Reservoir.
“Legacy sediment” describes excess fine-grained sediment like silt, clay and sand that collects as a result of human activity. According to Miller, this section of the watershed functioned as a wetland before the now-damaged dam was built and the legacy sediment accumulated.
Miller displayed photos of one area of the South River with “highly eroding” legacy sediment stretching 10 feet high.
“Removing this sediment will give us space to store water, space to store sediment nutrients, but it’s also preventing this eroding sediment from being mobilized and coming downstream where it’s forming enlarged bars in the South River, increasing bank erosion and flooding pressure,” Miller explained.
According to Starvish, removing the sediment would also help restore habitats for species that roamed the wetlands before the sediment piled up, as well as the river’s current crew of fish and other wildlife species that the state’s Natural Heritage & Endangered Species Program lists as either “threatened” or of “special concern,” like the marbled salamander, northern parula, riffle snaketail and wood turtle.
In 2016, the town pursued a river restoration project at the South River Meadow, removing 3,500 cubic yards of sediment and lowering the floodplain by about 3 feet. Along with the installation of boulder deflectors along the right bank, these changes have narrowed the river channel through the meadow by 20 feet, curbing erosion of the bank, Miller said.
“It’s working as designed,” he said. “This gave us the idea to keep looking for other opportunities.”
Besides excavating the 40,000 cubic yards of sediment, the two are also looking into lowering the South River floodplain by the historic Burkeville Covered Bridge at the corner of Ashfield and Main Poland roads. Unlike the other design, this project includes pathways for residents and visitors, a parking lot for vehicles at the top of the hill and a picnic area overlooking the river.
A graphic of the first proposed design for a walkway along the section of the South River between Ashfield and Main Poland roads in Conway. Credit: Graphic by GZA GeoEnvironmental Inc. 
A graphic of the second proposed design for a walkway along the section of the South River between Ashfield and Main Poland roads in Conway. Credit: Graphic by GZA GeoEnvironmental Inc. 
A graphic of the third proposed design for a walkway along the section of the South River between Ashfield and Main Poland roads in Conway. Credit: Graphic by GZA GeoEnvironmental Inc. 
A rendering of the third proposed design for a walkway along the South River between Ashfield and Main Poland roads in Conway, with a foot bridge connecting the west and east sides. Credit: Graphic by GZA GeoEnvironmental Inc.
Starvish outlined three potential plans for the walkway: a path only along the east side of the river; a path along both sides of the river, with a “low-water crossing” connecting the west and east side for visitors to wade through the water; and a pathway along both sides featuring a “more robust” foot bridge.
Although Starvish said the third option comes with a higher price tag, she described it as “more amenable” for visitors crossing.
“It’s exciting that there are a lot of opportunities for resilience work in the South River Watershed,” Starvish said.
Miller and Starvish reminded attendees of the information session that the projects remain in the early phases, and the pair will continue tweaking designs and pursuing permits in the next year. Depending on whether the town continues to earn MVP grants and which projects the Conway MVP Core Group members decide to prioritize, work on the “legacy sediment” removal project could start in 2028, Starvish estimated.
“One project isn’t going to solve everything,” Miller told attendees, “but it’s going to help, and that’s what we can do right now.”
