An environmental group’s planned removal of a local dam to help restore habitat for migratory herring and other fish species is gaining momentum following a recent regulatory ruling and a funding award.
The North and South Rivers Watershed Association seeks to demolish Peterson Pond Dam in Third Herring Brook, a 5-mile tributary to the North River that straddles the Hanover-Norwell line.
In February, the state waived the requirement of a full environmental impact report for the estimated $500,000 project, which the association is pursuing in partnership with Hanover Mall. Then in June, the Massachusetts Environmental Trust — funded through the sale of specialized license plates — awarded a $20,000 grant to support the dam removal, said Samantha Woods, the association’s executive director.
Woods said the state ruling would save the project time and money, while the grant would “help in leveraging additional state and federal grants.”
Hanover Mall, which owns the dam, has already pledged $75,000 to support its demolition after having previously contributed $25,000 for a feasibility study and permitting. Woods is optimistic the association will secure the funding needed for the project to go forward in late 2020 or early 2021.
Peterson Pond Dam is one of many such barriers erected in New England during Colonial times and the later industrial era to power mills. Most became obsolete by the early 1900s, but many remain in place.
In recent times, there has been a push to remove the antiquated structures to return migratory herring and other fish species whose use of the waterways was impeded in the past by the dams.
Over the past five years, two of four dams that stood in Third Herring Brook have been removed through efforts led by the Watershed Association: the Mill Pond Dam in 2014, and the Tack Factory Dam in 2017. Peterson Pond Dam would be the last to go: The association is not seeking to remove the fourth dam — the Jacobs Pond Dam — because that Norwell pond is a popular recreational resource. But the group hopes to install a fish ladder at the site.
Woods said there are signs the effort is having a positive effect. One is that blueback herring — which had continued to spawn downstream of the dams — have been spotted further upstream now that the dams are gone. And brook trout, confined until now to the Third Herring tributaries because dam activity made the brook too warm, have recently been seen in the brook.
Norwell Selectwoman Alison Demong, who previously worked for the association, is excited to see the progress made with the dam removals.
South Shore residents “value our natural resources, and I’m just grateful that we have a watchdog organization like the watershed association that has been able to focus on restoring the health to our waterways,” she said.
Ed Callahan, general manager of Hanover Mall, said for years the mall has tried to care for its section of the brook, which runs along the back side of the property, including by erecting fences to curtail trash dumping into the waterway.
He said PREP Property Group, which purchased the mall in 2016 and is preparing to redevelop it, is happy to partner in removing Peterson Pond Dam.
“To continue the goal of the watershed association to take these three dams down for the benefit of Third Herring Brook and the benefit of the fish species, that’s something we are on board with,” he said.