IRU helps win flows for scenic Twin Falls waterfall

The dramatic Twin Falls waterfall near Twin Falls, Idaho. (Photo by Kevin Lewis)

In a win for rivers and recreation, Idaho Rivers United and American Rivers have put a stop to Idaho Power’s plans to eliminate flows over 130-foot Twin Falls during certain times of year.

On April 17, 2014, the Federal Energy Regulatory Commission ruled in favor of Idaho Rivers United and American Rivers, who argued the Idaho Power proposal would “eliminate the unique photography and viewing opportunities as well as reduce the number of visitors spending money in the local area.”

Idaho Power had proposed to eliminate flows completely from September 1 to March 31 and in the early-morning and late-evening hours from April 1 to August 31.

“There has to be a balance between river flows and energy production, and FERC agreed that aesthetics and other uses deserved protection,” said IRU Conservation Director Kevin Lewis. 

FERC ruled that the economic benefit to Idaho Power of completely diverting the river at the Twin Falls Project does not outweigh the loss of aesthetic and recreational opportunities on the Snake River.

At 130 feet tall, Twin Falls is one of the three largest waterfalls on the Snake River. Before 1935, all of the Snake River plummeted over Twin Falls, which consisted of a north and south falls divided by a large bedrock outcropping. 

When Idaho Power began operating the Twin Falls Project in 1935 all of the flow over the south falls was diverted into the powerhouse. Despite this scenic loss, sightseers still arrived to view the formerly-dramatic falls.

In 1995, Idaho Power expanded the hydropower project and also eliminated most of the flow from the north falls. Following the successful protest by Idaho Rivers United and American Rivers, however, the new FERC license requires Idaho Power to release 300 cubic feet per second to sustain the north falls.