For the first time in recent years, the state Department of Energy and Environmental Protection announced Friday that it is closing portions of the West Branch Farmington River and the Farmington River to fishing because of the effects that drought conditions and extended periods of very high temperatures are having on fish in those areas.

High temperatures the past few weeks have had a significant effect on the waters of the two rivers.

During the past week, daytime temperatures have been well into the 90s, and nighttime temperatures have remained above 70 degrees. These temperatures have led to some fish kills along the river, DEEP said.

“High daytime temperatures with limited nighttime cooling — combined with a lack of rain and low stream flows — are causing fish in these rivers to suffer from heat stress,” DEEP Deputy Commissioner Susan Whalen said in a news release.

“The stressed fish — particularly trout — are seeking refuge by congregating at the mouths of a number of tributary streams, where cooler water is entering the West Branch Farmington River and Farmington River,” she said.

Whalen said fishing would put additional stress on the fish, and lead to increased mortalities.

“To protect these fish, we are establishing refuges where fishing is prohibited on portions of the West Branch Farmington River and Farmington River around the mouths of several tributaries,” she said.

Refuges include: East Mountain Brook (Hallock Brook) in New Hartford; Cherry Brook and Rattlesnake Hill Brook in Canton; Burlington Brook; Hawley Brook in Avon; and Unionville Brook, Hyde Brook and the Pequabuck River, all in Farmington.

DEEP also is asking the public to avoid swimming, wading and boating in the refuge areas, because those activities also would disturb fish.

DEEP is posting these refuge areas with closure signs. All water within 100 feet of these signs are now closed to all fishing.

This closure is scheduled to continue through Sept. 15, but may be shortened if conditions improve sufficiently, DEEP said. Violation of the closure is an infraction with a fine of $154.

“This is the first time in memory that we have found it necessary to take action like this to protect our fisheries on these rivers, and it is not a step we are taking lightly,” Whalen said.

“The West Branch Farmington River and Farmington River are very popular and well known to anglers, who are attracted to the area from around the world to catch both wild brown trout that spawn in those waters, as well as fish stocked by DEEP,” she said.

While some portions of the West Branch Farmington River and Farmington River remain open to fishing, DEEP asks anglers to consider avoiding being out during the hottest times of day and to consider fishing upstream of the Collinsville impoundment, where the water temperatures are cooler and the fish are less stressed.