Bringing oysters and other shellfish back to city’s shoreline would help improve water quality
By KEVIN PROFT/ecoRI News staff
PROVIDENCE — Around the turn of the 20th century, the Providence and Seekonk rivers teemed with oysters. The brackish conditions of the city’s waterfront supported an oyster population millions strong.
There were 5,000 acres of leased oyster beds in the Providence River and upper Narragansett Bay, according to the Narragansett Bay Commission (NBC). In an age of oil and railroad barons, Providence had oyster barons, said John Torgan, director of ocean and coastal conservation at The Rhode Island Nature Conservancy.
The local oyster industry peaked in 1911, and its decline was evident by the 1920s. A combination of factors, including polluted water and sedimentation, accounted for the drop-off. The Great Depression further repressed the industry, and then the hurricane of 1938 dealt it a blow from which it would never recover.
Rhode Island eventually banned shellfishing in the upper Narragansett Bay because of sediment and bacterial contamination. Since then, erosion and more sedimentation have further degraded oyster habitat along the Providence waterfront; oyster larvae latch onto hard structures such as rock and other oyster shells and can’t anchor onto the increasingly muddy habitat surrounding Providence today, Torgan said.
The Seekonk River was 37 feet deep in 1910, but sedimentation had reduced its depth to just 6 feet by 2010, according the NBC.
Rhode Island’s capital lost more than a tasty shellfish when its oyster population crashed. The ecological benefits of oysters are numerous. A single adult oyster can filter up to 50 gallons of water daily, removing nutrients and improving water quality. Oyster reefs, which develop as new oysters grow on older or dead oysters, act as coastal buffers, reducing wave action and erosion during storms and creating conditions that allow marsh habitat to expand.
As sea level rises and more frequent storms hammer the coast, oyster reefs offer a natural infrastructure solution to help keep the coastline intact. Additionally, reefs act as prime habitat for other marine life such as crabs and juvenile finfish.
An oyster population numbering in the thousands endures in the waters around Providence, according to Torgan, but compared to historical highs it’s down by some 90 percent. Since 2008, when the first phase of the NBC’s combined sewer overflow project was completed and began reducing pollutants and untreated sewage entering the upper bay, oyster numbers have increased in the Providence and Seekonk rivers, leading some to believe that the time is right for restoration of oyster and other shellfish reefs along the city’s waterfront.
Scheri Fultineer, department head of landscape architecture at the Rhode Island School of Design, believes it’s time for Providence oysters to make a comeback. She is helping lead a multiyear, collaborative effort to begin restoring shellfish populations along the Providence waterfront. She and her team are approaching a major milestone of the restoration effort: the deployment of a series of sculptural reefs into The Cove at India Point Park.
“Rhode Island has historically been an oyster state since the time of the Native Americans,” Fultineer said.
She said this restoration project invests in that shellfishing culture, while also helping the environment. Rhode Island has hundreds of miles of coast, and as sea level rises, it needs help adapting to prevent erosion, she added.
The project began in 2012 as an EPSCoR-funded course at RISD. Students from the landscape architecture department and the sculpture department collaborated with consultants from the University of Rhode Island, Rhode Island College and Roger Williams University to develop viable, sculptural shellfish habitat capable of engaging the public. The project resulted in five possible follow-up projects, including a Providence-based reef project that Fultineer and her collaborators were able to secure additional funding for in the form of a STAC grant.
Visibility was a big factor in choosing the Providence project, said Fultineer, who wants to maximize the project’s educational impact. Because the shellfish reefs will be placed in the intertidal zone, park-goers will be able to see the sea life growing on them at low tide.
Scientists know a lot about best practices for restoring shellfish habitat, Fultineer said, but getting the public to care is a different matter. To further fulfill the educational mission of the project, Fultineer plans to recruit local schools to help monitor the reefs once they are deployed.
Last summer, students from RISD, Roger Williams, Rhode Island College and Brown University experimented with materials and forms to determine which maximized oyster settlement. More than 40 experimental tiles, varying in texture, material and shape, were deployed into tanks and open water at the Roger Williams University hatchery and were monitored for shellfish and sea life settlement, according to Dante Gamache, a research assistant in RISD’s landscape architecture department. Some tile monitoring studies also were conducted at Bold Point in East Providence, across the river from India Point Park.
Gamache and three colleagues also designed and built three reef prototypes. One consists of staggered concrete plates around a central vertical spine, while the other two are spherical in nature.
“They’re all different, and each has advantages and disadvantages,” said Emily Vogler, a landscape architecture faculty member at RISD who gave a recent presentation about the project at the Community Boating Center at India Point Park.
Each prototype is relatively small and modular, so it can be deployed without heavy equipment, either individually or clustered. The prototypes maximize surface area for shellfish to settle on by offering an interior and exterior surface, a rare feature among artificial reefs, according to Vogler. The interior spaces also provide protective habitat for juvenile finfish, she said.
Three of each prototype will be deployed in the water off India Point Park. While the small scale of the deployment means the environmental benefits will be minimal, Vogler said the educational benefits and the ability to collect more data about each prototype are important.
“We see this as an opportunity to discuss the role of habitat in public parks,” said Vogler, noting that most parks are just lawns with trees. “There’s an opportunity to have a conversation about urban ecology.”
The initial reef proposal included a larger deployment of prototypes, but Friends of India Point Park (FIPP) was resistant to the idea.
“Initially, we were quite concerned because there were a lot of forms in the water,” said David Riley, co-chair of FIPP. Riley said he was concerned about the community reacting negatively to seeing artificial reefs in what he described as the most beautiful feature of the park. “We have spent 15 years trying to minimize the impact of the built environment in the park,” he said.
After the proposal was scaled back, FIPP endorsed it, and Riley is now enthusiastic about the project.
Before the reefs can go in the water, the team needs to obtain the proper paperwork, including a 3-year trial permit from the Coastal Resources Management Council (CRMC). Following the trial period, there will be another discussion about how to proceed, Vogler said.
Health concerns about people harvesting and eating oysters off the reefs have been raised, according to Fultineer. Shellfishing is illegal north of Rocky Point in Warwick because of high levels of pollutants in the water.
“Siting the reefs so people can see, but not get to them is important,” Fultineer said. She said the goal of the project is environmental restoration, not growing culinary oysters.
The Nature Conservancy’s Torgan noted that while he understands the health risk, oysters are already growing along the Providence waterfront. “We aren’t going to be able to keep it a secret,” he said. “They are here and it’s a good thing.”
Torgan suggested that rather than prevent oyster restoration in the upper bay, and miss out on the environmental benefits of healthy oyster reefs, existing laws preventing taking oysters simply need to be enforced.
Vogler said the team would like to deploy reefs at other locations in Narragansett Bay or in the brackish rivers north of India Point Park. Comparing data between sites would be valuable, she said. Longer term, Vogler said the team hopes to create open-source plans detailing how communities around the world can create and deploy reefs where they live.