The economically important Little Narragansett Bay watershed is feeling the pressures of development, population growth and climate change just like the better-known bodies of water to the north and south.
By FRANK CARINI/ecoRI News staff
ABOARD THE ELIZABETH MORRIS — Little Narragansett Bay is quietly tucked away between its noisier neighbors — Narragansett Bay and Long Island Sound. But this watershed on the Rhode Island-Connecticut border plays a vital role in southern New England’s economy. Boats of all sizes, from yachts to canoes, dot the water, especially on summer weekends. Tourist visit the area to swim, fish, observe wildlife, dine and shop.
The fact that the 317-mile Little Narragansett Bay/Pawcatuck River watershed is stressed and impaired is cause for concern, both economically and environmentally.
“This is our economy,” David Prescott, Save The Bay’s South Country coastkeeper, said shortly into a July 16 tour of the watershed. “We have to make sure we protect it.”
Before the Elizabeth Morris departed Viking Marina in Westerly, R.I., Save The Bay’s executive director, Jonathan Stone, told the 20 or so journalists, elected officials and scientists on board that the watershed needs protection from development, population growth and climate change.
“This is an incredibly beautiful space,” Stone said. “Its habitat and aquatic life is very valuable. The watershed is economically important to the region. It’s one of the gems in this part of the world.”
Little Narragansett Bay doesn’t garner the same attention that Narragansett Bay and Long Island Sound do, but this important economic, environmental and recreational resource is threatened by many of the same concerns — development pressures, human impacts and a changing climate. Because of its topography and shallow depths, it also faces different challenges.
The Pawcatuck River estuary has been studied for decades by state agencies, universities and environmental groups. While much has been done to clean up the pollution caused by industrial and manufacturing businesses, contaminated runoff from roads, roofs, lawns and farms remains a problem.
Prescott has been monitoring the watershed’s water quality and ecological health for the past seven years. He said Little Narragansett Bay is stressed by elevated bacteria levels, high nutrient loads, large, thick mats of macroalgae, poor flushing in shallow coves, and decreased dissolved oxygen levels. These stressors are threatening water quality, marine and coastal ecosystem health, and the region's recreational value, he noted.
Elevated bacteria readings have been documented in both wet and dry weather conditions in the upper estuary. Near the downtowns of Westerly and Pawcatuck, Conn., a number of outfall pipes directly discharge into the Pawcatuck River.
Save The Bay touted last week’s invitation-only outing as a call to action, to urge local communities — and not just Westerly and Stonington, Conn. — and their residents to help mitigate pollution impacts. The Providence-based nonprofit also would like agencies and officials in both states to better enforce the environmental regulations that protect this shared natural resource.
The environmental group is pushing watershed municipalities along the coast and upstream to develop plans to better manage stormwater runoff, ensure septic systems are working properly and to closely monitor the watershed.
Much like the problems facing areas of Narragansett Bay and Long Island Sound, contaminated stormwater and combined sewer overflow washing into Little Narragansett Bay are causing parts of the bay to degrade. This runoff and overflow carries oil, gasoline and grease, lawn fertilizer, pet waste and bacteria. This pollution has closed part of Little Narragansett Bay to shellfishing since 1991.
Since 2007, when Save The Bay opened its South Coast Center in Westerly, it has been testing, in cooperation with the University of Rhode Island’s Watershed Watch program, in six locations in Little Narragansett Bay/Pawcatuck River, documenting water temperature, clarity, salinity, and nutrient, dissolved oxygen and pH levels.
While continued monitoring shows water quality is impaired and problems persist, scientists need more data to fully understand the bay and its watershed, Stone said.
Much of the area in the watershed is built up and covered with impervious surfaces, which rushes stormwater pollution into Little Narragansett Bay. In fact, a third of Rhode Island’s runoff drains into the Pawcatuck River watershed, according to Prescott.
Thanks to large amounts of nitrogen, much of it from lawn fertilizers, contained in this runoff, thick mats of macroalgae — called “black ooze” or “black mayonnaise,” depending on whom you are speaking with — cover much of the bottom of Little Narragansett Bay between Watch Hill and Sandy Point.
This patchwork blanket of algae, which gives off a rotten-egg smell when a piece is pulled into a boat or some of it washes into shore, creates low-oxygen zones that suffocate eelgrass and iconic New England marine life such as oysters and scallops. In some places, this decaying organic matter is several feet thick and spreading, according to Prescott.
The University of Connecticut and the University of Rhode Island are both studying this algae formation, which shows no signs of disappearing.
“It’s not quite a dead zone, but it isn’t really what it should be,” Prescott said. “We don’t want to see Little Narragansett Bay any more impaired than it is now.”
This algae has always been at the bottom, but the amount of it is growing and impacting the natural flushing of the bay.
Exacerbating the bay’s flushing problem is the fact Sandy Point, a narrow island that was cut off from mainland Connecticut by the 1938 hurricane, is slowly moving to the north, creating a barrier that is impairing the bay’s ability to flush excess nutrients.
Erosion and more frequent and severe rains also are changing the currents, leading to poor flushing of the bay’s many shallow coves and the buildup of macroalgae.
A growing amount of the black mayo is washing up on the Borough of Stonington’s shore and having a huge impact on the oldest borough in Connecticut.
“This organic matter is decaying and smells awful,” Prescott said. “Residents have to keep their windows closed.”
Don’t feed the birds
Prescott noted, on more than one occasion during the two-hour cruise, the water-quality problems created by the feeding waterfowl such as Canada geese and swans, whose waste contributes to increased bacteria/nutrient levels.
Up until about four years ago, hundreds of swans and Canada geese often congregated at the mouth of the Pawcatuck River, because an elderly Stonington resident was routinely feeding them. After local officials explained the negative impact all these birds were having on the river’s ecosystem, the woman stopped and most of the birds left.
Many of the swans and geese that remain are found on private lawns that stretch to the riverbank. Long, native grasses and other shoreline vegetation would help keep waterfowl from congregating and would better filter runoff pollutants.
In fact, according to Save The Bay, there are a number of individual actions that, combined with state and local programs, would help minimize watershed impacts. Land conservation, salt-marsh protection and pump-out programs are among the measures state agencies and local groups have taken to protect the watershed.
Among some of the environmentally friendly actions individuals can take include: replacing your cesspool, installing a rain garden, using a rain barrel, properly maintaining your septic system and/or fertilizing and mowing your lawn less.
“Having a lush, green lawn is part of our culture and it’s hard to make changes,” said Cindy Sabato, Save The Bay’s director of communications. “If you can’t or don’t want to replace your lawn with a rain garden or native bushes and shrubs, apply less fertilizer and don’t fertilize before it is expected to rain.”