Testing the waters: Dedicated volunteers create storehouse of valuable data

Testing the waters: Dedicated volunteers create storehouse of valuable data


On water-testing day, it’s good to be the coastkeeper.

Twice a month between May and October, Save the Bay coastkeeper David Prescott goes out on the Pawcatuck River and Little Narragansett Bay to take water samples. If the rain and wind aren’t too unbearable, Prescott heads out on the water for half a day of sampling and testing. Over the past year, he’s also taken Annakate Hein, an AmeriCorps volunteer with Save the Bay and a future environmental educator.

On the first sampling day of August, the river was smooth, the sun was shining, and the day was glorious.

“These are the mornings I live for,” said Prescott, from behind the wheel of Save the Bay’s 18-foot Parker, named Coastkeeper II.

Prescott is one of 400 monitors, mostly volunteers, who provide samples for testing through the University of Rhode Island’s Watershed Watch program.

This is the program’s 26th season of water testing, said director Linda Green, and 275 sites in Rhode Island, southeastern Connecticut, and southern Massachusetts are now regularly sampled.

Six of those sites are monitored by Prescott, who samples from several areas south of the Route 1 bridge in the Pawcatuck River, including directly north and south of the two wastewater treatment plant outlets.

In Little Narragansett Bay, he takes samples off of Barn Island, Sandy Point, and Watch Hill Harbor. The sites were chosen based on data from a survey by Rhode Island and Connecticut agencies, he said. By keeping sites the same, he’s generated six years of data on the same places. The consistency’s important; it takes at least five years of data to spot trends through the noise, he explained.

“It gives a really good overall picture of the river,” Prescott noted.

This is Save the Bay’s seventh year of testing in the Pawcatuck River watershed, and the sixth in conjunction with Watershed Watch. The sites have remained roughly the same, although the Watch Hill Harbor site was added after the first year, and the Sandy Point collection point had to move when the island did after Superstorm Sandy. (On the first sampling day after the October 2012 storm, Prescott intended to navigate to the coordinates he used off Sandy Point, but the location was now dry land. He now samples from about 30 feet away.)

Going out at set times, regardless of the weather, provides valuable information, Prescott because weather changes can alter the features of a waterway.

“Rainstorms have a huge impact on the health of the river,” he said.

The frequent trips also allow him to make pertinent observations, such as the one about Sandy Point’s mobility.

“The island’s moving,” he said. “There’s no question. The island’s been moving for a while.”

He could also point out different species in the water, and whether or not they were plentiful on any given day.

“We’re seeing a lot more warm-water species,” he noted.


Lately, he’s been using his time on the water to assist the University of Rhode Island and the Rhode Island Department of Environmental Management with a study of blue crabs. He sets out traps for the blue crabs, a species that prefers warmer water, and documents the number, size and gender of his catches.

Twice a month, Prescott tests for dissolved oxygen, salinity, clarity, and chlorophyll. Once a month, he also tests the water for bacteria and nutrients.

Some of the tests are chemical, like the dissolved oxygen test. After collecting water samples in specially designed jars that prevent atmospheric oxygen from contaminating the sample, specific chemicals are added to fix the dissolved oxygen in the water. The dissolved oxygen is measured later, in a laboratory. Others are physical, like the clarity test. A black-and-white instrument called a Secchi disk is lowered into the water and the operator measures how deep it can go before it’s no longer visible. Salinity is measured by putting a few drops of water on a refractometer, then visually measuring the results.

And some tests are a combination of the two. Chlorophyll, which is a measure of how much plankton is in the water, is measured by using a long rod to take deep water samples. The water is taken back to the Save the Bay office in Westerly, where the chlorophyll is separated from the water by letting the sample flow through filter paper. The paper is then dried and frozen, and taken to Watershed Watch for testing once a month.

It was that type of data that was missing when the Wood Pawcatuck Watershed Association, in conjunction with University of Rhode Island hydrology professor Arthur J. Gold, started Watershed Watch, according to Denise Poyer. There were 10 testing sites initially, said Poyer, the association’s program director. Now, the association samples over 30 sites, and other organizations have joined the effort.

Among the many agencies and groups that use Watershed Watch’s vast storehouse of data is the Rhode Island Department of Environmental Management. The department is required to report this data to the federal Environmental Protection Agency, Poyer said, but lacks the resources to test everything.

“Their resources have been limited, and they’re even more limited now,” she noted.

There are many groups that sample water in the Pawcatuck River watershed besides Save the Bay and the watershed association. The western edge of the watershed is monitored by CUSH, Stonington-based Clean Up Sound and Harbors.

Claire Gavin, a retired toxicologist who started CUSH’s water-sampling program, doesn’t need a boat to take water from the Anguilla Brook.

“We do a lot of wading,” she said.


There aren’t many places where the brook is accessible to CUSH’s volunteers, Gavin said. Some areas are swampy, while others are in residential backyards. Among the sites where they can take samples is where the brook flows next to the Handlebar Café in Pawcatuck.

The Anguilla Brook is a high-quality trout stream, Gavin said, and the major freshwater inlet for Wequetequock Cove, which contains a great deal of algae. Any pollution picked up by the brook will flow into the cove.

CUSH regularly tests for chlorophyll, dissolved oxygen, salinity, and temperature. The organization also measures the stream flow. When the water’s too cold or too deep, CUSH volunteers use an improvised golf ball retriever to take the sample, invented by Jean Pillo of the Eastern Connecticut Conservation District.

“We try for half way between surface and bottom,” Gavin said.

Once a month, there’s a test for phosphorus and nitrogen levels.

“The nitrogen is what’s of real interest to us, because it fertilizes the algae in the cove,” she said.

Gavin stepped up to the plate to run CUSH’s water-sampling program at the request of Gracelyn Guyol, CUSH’s founder and former president. From both her career and her childhood exploring Ohio marshes, Gavin realizes how important clean water is, she said.

With her on this particular August day was David Moore, another sampling volunteer. An avid fisherman and retired environmental toxicologist, Moore noted that he also understands the importance of clean water.

“I just wanted to make certain we do our part,” he said.

CUSH is closely monitoring Wequetequock Cove, Gavin said, because of the dense algae.

“Its water quality is really low,” said Gavin. “There’s not a whole lot of water going into that cove.”

The Anguilla Brook appears to be the cove’s major freshwater source, and, based on salinity measurements, the CUSH volunteers don’t see a lot of water mixing between the cove and Little Narragansett Bay.

“It’s very mysterious,” said Gavin.

Prescott has also seen readings that indicate something possibly anomalous. In Watch Hill Harbor, where many people swim, boat, and play, there have been some “weird spikes” in the bacteria counts, he said.

Other groups that run sampling programs in the area include the North Stonington Citizens Land Alliance and the Watch Hill Conservancy, among others. The groups are careful not to duplicate each other’s work.“There’s a lot of collaboration that goes on,” said Moore.

All of the sampling programs in this area receive their training, equipment, and laboratory analyses from Watershed Watch, Green explained, while volunteers provide the legwork and time commitment. Watershed Watch works with agencies to determine which water bodies need testing, and trains volunteers in the spring. Although there is a large group of dedicated volunteers, Green said, they could always use more volunteers in urban areas statewide.

Without testing, Green asked, how could anyone know whether the water around them is safe?

“We all love the water and we want to enjoy the water, but we want to do it safely,” said Prescott.

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