Restoring the Pawcatuck
By ALAN
DESBONNET/ecoRI.org News contributor
Historically, dams
were erected throughout New England during the heyday of the Industrial
Revolution to harness the power of running water for the production of hard
goods, ranging from textiles to weaponry. Today, many of these dams still
exist, often as no more than relics of a bygone manufacturing era.
The Pawcatuck River borders Rhode Island and Connecticut, and is the main tributary feeding into Little Narragansett Bay. It once served as a migratory fish pathway connecting saltwater and freshwater environments.
The Pawcatuck River borders Rhode Island and Connecticut, and is the main tributary feeding into Little Narragansett Bay. It once served as a migratory fish pathway connecting saltwater and freshwater environments.
Now, decades after adoption of the interstate management plan, accomplishing the goal of rehabilitating the river for fish migration is tangible. Open access to spawning and feeding habitat for salmon, alewives, shad, Atlantic herring and blueback herring, to name a few, is poised to occur.
Restoration of free and open access to riverine ecosystems is neither simple nor straightforward, however. It’s a highly complex undertaking that crisscrosses environmental, social and economic interests.
“People live along the river, there are businesses on the river, and there is a large contingency of user groups that recreate on and along the river,” said Chris Fox. “And all this has to be taken into consideration as part of the goal of fish passage. The fish are only part of a pretty complicated jigsaw puzzle.”
Fox is executive director of the Wood-Pawcatuck Watershed Association (WPWA), the leading environmental organization involved in creation of the 1992 management plan. The WPWA was the first group in Rhode Island to undertake a permitted dam removal project, and its work, in cooperation with regulators, has led to a new way of thinking and permitting.
Open space
This project has
opened about 1,500 acres of habitat, much of it relatively undisturbed,
undeveloped riparian ecosystem, that is mighty inviting as spawning and forage
area for shad, herring and salmon, according to Fox.
Despite the benefits of dam removal, the Horseshoe Falls in Shannock is both scenic and historic, and public opinion suggested removal wasn’t going to be an agreeable solution.
“There was no way residents were going to be happy with a part of their history and culture being taken way, whether for fish or otherwise,” Fox said. “There was little opposition to enhancing fish passage, but lots with regard to removal of a cultural icon of such historic value and significance to the town and the people who live there.”
Unfortunately when logjams like this occur in the resources management realm, the end result is often litigation and lasting bitterness, or at the very least, a dissatisfactory compromise.
“People in this area highly value the river as a resource, and truly did want to see fish have free passage,” Fox said. “So they asked us to find another way, and we did by getting creative.”
The project team came up with a design that allows the Horseshoe Falls to remain intact, but is modified to include a non-intrusive fish passageway that guides fish around the dam, and includes an innovative eel way to promote passage of the American eel, which is a species of special concern. The passageway is also crafted in a way that blends into the dam site and adjacent properties, to the extent that the rockwork is historically correct in both texture and color with the original, historic dam and neighboring stone walls.
While the Horseshoe Falls presented perhaps the most difficult challenge, there is still more to do before the watershed provides free and open access from Little Narragansett Bay into Worden’s Pond.
The dam at Kenyon Industries holds back enough water for fire suppression at the facility, and is a last major hurdle. Removal of this dam would put a burden on the company, which would then need to implement expensive fire suppression options that it can ill afford. So, Fox and the project team decided to create a type of fish passage that is relatively new but has proven successful in other river restoration — a natural rock ramp that presents fish with steps to “climb” up and over the retention basin.
“While removal of the dam would be the ideal ecological solution,” Fox said, “a compromise that allows fish passage while still allowing adequate water retention for fire suppression was the practical outcome that provided the biggest ecologic bang with the smallest economic sting to our industry partner.”
Despite the benefits of dam removal, the Horseshoe Falls in Shannock is both scenic and historic, and public opinion suggested removal wasn’t going to be an agreeable solution.
“There was no way residents were going to be happy with a part of their history and culture being taken way, whether for fish or otherwise,” Fox said. “There was little opposition to enhancing fish passage, but lots with regard to removal of a cultural icon of such historic value and significance to the town and the people who live there.”
Unfortunately when logjams like this occur in the resources management realm, the end result is often litigation and lasting bitterness, or at the very least, a dissatisfactory compromise.
“People in this area highly value the river as a resource, and truly did want to see fish have free passage,” Fox said. “So they asked us to find another way, and we did by getting creative.”
The project team came up with a design that allows the Horseshoe Falls to remain intact, but is modified to include a non-intrusive fish passageway that guides fish around the dam, and includes an innovative eel way to promote passage of the American eel, which is a species of special concern. The passageway is also crafted in a way that blends into the dam site and adjacent properties, to the extent that the rockwork is historically correct in both texture and color with the original, historic dam and neighboring stone walls.
While the Horseshoe Falls presented perhaps the most difficult challenge, there is still more to do before the watershed provides free and open access from Little Narragansett Bay into Worden’s Pond.
The dam at Kenyon Industries holds back enough water for fire suppression at the facility, and is a last major hurdle. Removal of this dam would put a burden on the company, which would then need to implement expensive fire suppression options that it can ill afford. So, Fox and the project team decided to create a type of fish passage that is relatively new but has proven successful in other river restoration — a natural rock ramp that presents fish with steps to “climb” up and over the retention basin.
“While removal of the dam would be the ideal ecological solution,” Fox said, “a compromise that allows fish passage while still allowing adequate water retention for fire suppression was the practical outcome that provided the biggest ecologic bang with the smallest economic sting to our industry partner.”
All access
Twenty years after
adoption of the interstate management plan, the Pawcatuck River watershed is
nearing the goal of open access for fish to move up and down its length. The
total cost of dam removal and building fish passages is estimated to be $3.5
million. Fox is aware that even project proponents will want to know: “Was it
worth it?”
“Removing barriers along the river, regardless of anything else, restores the ecosystem to a natural state and that can’t be a bad thing,” Fox said.
Granted, things have changed in the watershed, and will continue to do so, particularly in light of climate change. However, Fox said, “We’ve provided the opportunity [for the watershed] to respond naturally to change, and that, in and of itself is worth the cost in time, effort and real dollars.”
A big challenge according to Fox, will be monitoring the fish passage, which “is usually a low priority for funding, especially in today’s trying economy.” The state Department of Environmental Management (DEM) and the WPWA will perform, at a minimum, monitoring for presence or absence of migratory species. But Fox noted that biologists are keen to find funding to support more aggressive fish sampling practices that will provide the ability to better measure outcomes of the restoration efforts.
Alan Desbonnet is Rhode Island Sea Grant’s assistant director. He was part of the Sea Grant effort that designed the interstate management plan. This story originally appeared in the Summer/Fall 2013 edition of 41°N, a publication of Rhode Island Sea Grant and the Coastal Institute at the University of Rhode Island.
“Removing barriers along the river, regardless of anything else, restores the ecosystem to a natural state and that can’t be a bad thing,” Fox said.
Granted, things have changed in the watershed, and will continue to do so, particularly in light of climate change. However, Fox said, “We’ve provided the opportunity [for the watershed] to respond naturally to change, and that, in and of itself is worth the cost in time, effort and real dollars.”
A big challenge according to Fox, will be monitoring the fish passage, which “is usually a low priority for funding, especially in today’s trying economy.” The state Department of Environmental Management (DEM) and the WPWA will perform, at a minimum, monitoring for presence or absence of migratory species. But Fox noted that biologists are keen to find funding to support more aggressive fish sampling practices that will provide the ability to better measure outcomes of the restoration efforts.
Alan Desbonnet is Rhode Island Sea Grant’s assistant director. He was part of the Sea Grant effort that designed the interstate management plan. This story originally appeared in the Summer/Fall 2013 edition of 41°N, a publication of Rhode Island Sea Grant and the Coastal Institute at the University of Rhode Island.