Hundreds of miles in Clark Fork River system now reopened to native Montana trout and other fish species
The arrival of spring has warmed the Clark Fork River, enticing the first fish to climb the new fish ladder at PPL Montana’s Thompson Falls hydroelectric plant.
“Climbing the new fish ladder may seem instinctively routine to the migrating fish, but it means a great deal to everyone who values Montana’s rich fisheries habitat,” said Mark Wilson, field supervisor with the U.S. Fish and Wildlife Service’s Division of Ecological Services in Helena.
“The advanced fish passage system that PPL Montana funded, built and dedicated last year is helping one of the great symbols of Montana’s legendary fisheries habitat — the native bull trout — reach its spawning area on the Clark Fork River,” Wilson said.
Dedicated in September and funded entirely by PPL Montana, the Thompson Falls ladder was built in collaboration with federal and state fisheries agencies and the Confederated Salish and Kootenai Tribes. It has reopened hundreds of miles of the upstream Clark Fork River and its tributaries for bull trout — listed as threatened by the U.S. Fish and Wildlife Service — and westslope cutthroat trout and other fish species.
“Several weeks ago we monitored the arrival of an adult rainbow trout, the first fish that climbed the ladder and was released safely into the upstream reservoir,” said Jon Jourdonnais, manager of hydro licensing and compliance for PPL Montana.
“Montana enjoys a healthy, diverse and dynamic river fisheries population, and PPL Montana is proud to do its part, in collaboration with agency partners, to protect this valuable natural resource,” he said.
An upstream movement of fish is expected in the coming weeks as spring water temperatures continue to increase, supporting the general upstream migration, Jourdonnais said.
Thompson Falls’ steel and concrete ladder system — which replaced an experimental, small-scale temporary fish ladder used since 2003 — has 48 step pools that permit fish to gradually ascend about 75 feet to the top of, and over, the dam.
According to the U.S. Fish and Wildlife Service, it’s the first full-length fish ladder in the continental United States specifically designed to accommodate bull trout, a federally listed threatened species. It’s also the tallest fish passage facility of its kind in Montana.
Advanced biological monitoring, trapping and tagging technology, and adaptive ladder operations, will allow fisheries biologists to better support and enhance fish movement patterns and timing of runs in the Clark Fork River.
The Thompson Falls fish ladder project is part of PPL Montana’s federal operating license in compliance with the Endangered Species Act.
PPL Montana provides safe, reliable energy from coal-fired power plants at Colstrip and Billings, as well as 11 hydroelectric plants along West Rosebud Creek and the Missouri, Madison, Clark Fork and Flathead rivers. It has a combined generating capacity of more than 1,200 megawatts and has offices in Billings, Butte and Helena. PPL Montana and its 500 employees are dedicated to Montana and its communities, supporting educational, environmental and economic development programs across the state. PPL EnergyPlus operates a trading floor in Butte that markets and sells power for PPL Montana in wholesale and retail energy markets throughout the western United States. PPL Montana and PPL EnergyPlus are subsidiaries of PPL Corporation (NYSE: PPL). More information about PPL Montana is available at www.pplmontana.com.