DEEP spearheads new method to improve stream management efforts

A new cost-effective method to monitor stream connectivity — which is vital for a healthy fish habitat — has been developed by the state Department of Energy and Environmental Protection.

DEEP said it deploys trail cameras at seven “study” streams around the state and set them to take a photo every hour. The photos are saved to a memory card, and collected every three to five weeks.

“It’s a method that allows us to begin to identify the issues,” Corinne Fitting, a supervising environmental analyst with DEEP, said in a statement. “Once you’ve documented impact, the next steps are to figure out why and how we can deal with it, but the first step is saying ‘there’s a problem here,’ and the trail cameras are allowing us to do that.”

For many fish species, including the brook trout, a healthy stream provides the environment for a full range of life activities — shelter, food and reproduction. But low water levels can present problems, whether caused by man-made interventions such as dams, or natural phenomena like the statewide drought seen this year.

Stream connectivity during droughts is a concern in the Water Planning and Management Division of DEEP, the statement said.

Gauging stations that cost $20,000 to $25,000 to install, with an annual operating and maintenance cost of $15,000, is one way to measure stream flow discharge, according to DEEP. But since 2017, DEEP staff has used digital trail cameras, at a cost of about $500 per unit, at seven streams around the state to successfully evaluate connectivity.

Now, DEEP hopes to build upon its success.

Christopher Belluci, who co-authored a study based on DEEP’s work in 2017, said the measurements meant that several miles of streams have been added to the state’s “Impaired Waters List.”

“We’ve increased the miles that we attribute as flow-impaired substantially in part because of this method, and now we can feel fairly confident that yes, we have evidence, we have metrics that we’ve calculated,” Belluci said.

Philip Trowbridge, assistant director of DEEP’s Water Planning and Management Division, said having a process to identify areas where there isn’t enough water and streams are going dry will better inform planning documents and decisions on managing water balances.

Currently, DEEP staff have about 30 trail cameras deployed.

Given the amount of time required to process this data, the news release said staff are continuing to find innovative ways to review photos and categorize them.

Trowbridge said of the three main stressors contributing to stream impairment — nutrients, urban runoff and flow — the most challenging to measure previously was flow.

DEEP has deployed trail cameras to monitor stream levels as a cost-effective method to better inform stream management efforts. A still photograph taken at the Mill River in Cheshire on Sept. 25, this stream is Category 1 — completely dry.

“I’d say this was a gamechanger in our ability to investigate and follow-up on localized issues for one of our major stressors,” he said.

The images were then evaluated and placed into one of six categories of connectivity established by staff, who were trained in order to standardize image interpretation. Categories

1-3 represent streams at different levels of disconnected flow, with Category One being completely dry. Categories 4-6 represent streams at different levels of connected flow, with Category Six representing healthy flows above “bankfull” discharge.