LITTLE COMPTON, R.I. — For the past four summers, the town has been working on a study to answer an important question: Does Little Compton have enough water?

Although the data collected doesn’t warrant any alarm for the current condition of the town’s water supply, the study does highlight issues with the supply that could worsen in the future without attention.

There are two big challenges for local water supply resilience that spurred the Conservation Commission to study it, Don McNaughton, the chair of the commission, said: Everyone in the area relies on wells and those wells draw on pockets of water caught in fractured bedrock. 

Although there are some shared wells in town, there is no municipal water supply that the town can rely on, McNaughton said.

“We have to care for our water supply because there is not help coming from elsewhere,” he said.

If Little Compton saw major issues with its supply, there isn’t infrastructure to pipe water in from a different part of the state, and trucking water is possible but expensive.

Unlike many other parts of the state, Little Compton has a bedrock aquifer that doesn’t absorb and retain water the way aquifers in sandy soil do. (Adam Yorks, who tests household wells for the study, put it like this: “We don’t have a well that we’re sticking straws through.”)

The bedrock fractures the wells tap into are “somewhat random,” said University of Rhode Island professor Thomas Boving. “And it is very difficult to predict where those fractures are in the first place.”

Boving, who is a professor of civil and environmental engineering and geosciences and has helped conduct the Little Compton study during the past few years, said that can make it hard to tell how much water an area has.

With these challenges in mind, the Conservation Commission decided to test household wells in the summer, which is the highest period of demand on water because of the increase in use for things such as pools, landscaping, and an influx of visitors to second homes and rentals.

More than 10% of the town’s households agreed to participate. Starting in summer 2019, wells were tested for measures like water temperature, pH, and electric conductivity in July and then again in September.

The study shows that overall water quality is good in Little Compton, but the supply is reliant on precipitation levels.

Electrical conductivity — which correlates to the concentration of dissolved solids including salt, septic waste, and fertilizer in the water — fluctuates with the amount of rain Little Compton gets.

The summers of 2019 and 2021, which saw normal to high precipitation, tested normal for salinity and conductivity, Boving said. But in 2020, when there were dry conditions, the conductivity went up.

Those readings could indicate saltwater intrusion, which happens when a well has been so depleted of fresh water that salt water from the nearby ocean works its way into the negative space.

The high conductivity during drier years could also show the aquifers weren’t being replenished with much fresh water to dilute solvents from septic systems, homes wastes, and fertilizer, according to the study summary.

For now, the testing shows the more than 150 wells included in the study do not have unsafe levels of any of those dissolved solids.

“We saw an increase in electric conductivity but not to the point where the water turns into spaghetti water,” Boving said. “What we have right now is kind of a canary in the coal mine. We’re not at the point where people have to shut down their wells.”

“The fact that precipitation levels so quickly affect [conductivity readings] is indication that our freshwater resources, particularly near the coast, are finite in nature,” according to the study summary. “It hints at our vulnerability to drought and, in coastal locations, to saltwater intrusion that will be exacerbated by sea level rise.”

Both high concentrations of salts and other pollutants could also increase during more extreme periods of drought, which are expected in Rhode Island as global temperatures rise, Boving said.

Carol Trocki, a member of the Conservation Commission who has been involved in the study, said she hopes the data will “get the conversation started” about the precariousness of freshwater resources.

Trocki noted that although residents shouldn’t be worried about their water now, it’s important to start thinking about what else should be studied and how the town, if it needs to, might remedy potential problems.

The analysis of the data collected for the study this past summer will be finalized this winter and added to the last three years, McNaughton said.

More data is being tracked through a “continuous logger” that was installed at a well near the coast and collects water quality information throughout the year. Another logger might also be installed at a well near the Tiverton/Little Compton line, McNaughton said.

McNaughton has already brought the study to several neighborhood and community groups to make them aware of the potential issues and what they can do to protect the local water supply, such as reducing use and preventing contaminants from entering the supply.

“The best way to prepare for our future is to care for our water now,” he said.

Colleen Cronin is a Report for America corps member who writes about environmental issues in rural Rhode Island for ecoRI News.