For the week of April 23 - 29, 2003

Elkhorn Creek
rising from the dead

Species diversity returning with water

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By GREG STAHL
Express Staff Writer

For a short stretch of Elkhorn Creek downstream from the Elkhorn Golf Course, Mother Nature is slowly reclaiming her natural processes.

This is the third consecutive spring that a half mile-long stretch of the creek has flowed in its historic channel, and water quality and species diversity in the area are on the upswing, said Stef Frenzl, the Wood River Land Trust’s Elkhorn Creek project coordinator.

Wood River Land Trust Elkhorn Creek Project Coordinator Stef Frenzl said the natural system at Elkhorn Creek is slowly reclaiming itself with some ongoing prodding and maintenance. Express photo by Willy Cook

"My overall feel is that it’s exciting," Frenzl said. "It’s really awesome to see people turning what I consider a degraded system, which is a straight narrow system where there’s no habitat, and turning it around."

In the winter of 2000, water was diverted away from a straight, narrow bypass canal and routed into the meandering historic channel. It was the first time the water was turned on in the original system in 40 years.

That winter, the water slowly crept down its long-abandoned, meandering pathway, overtaking sagebrush, desert grasses and thin icings of snow.

"This is so cool," Wood River Land Trust Executive Director Scott Boettger said as he pranced around enthusiastically. "This whole area will become a riparian corridor, a ribbon of life."

Now, after three years of springtime flows, this ribbon of life is slowly taking hold. Riparian plants—along with several non-native species—have reclaimed parts of the historic channel, and wetlands species like beavers, rainbow trout and aquatic insects have returned.

"Last year was the first in 50 years that we actually were able to video record spawning rainbow trout in that system," Frenzl said. "The reason that hasn’t happened in so long is there have been two dams preventing access to that drainage."

In addition to restoring flows to the historic channel, two fish ladders were installed in the system to enable the native rainbow trout to spawn. The nearby Sunrise Pond was also partially filled to increase riparian habitat. The pond had become stagnant because of tinkering with nature’s original designs.

Frenzl said some of the most exciting developments at Elkhorn Creek are related to the arrival of industrious beavers.

"The beavers have helped our restoration project," Frenzl said. "Although our project did not help the beaver move in, when they did move in, they helped our project."

First, beavers helped increase the amount of wildlife habitat by building dams, which create more wetlands.

Second, beaver ponds have helped filter and clean the system’s water.

"The water is definitely cleaner directly after a beaver dam than before," Frenzl said. "If beaver dams weren’t there, the water quality would definitely be worse."

Third, the dams help store water that otherwise might flush through the system during spring runoff. They continue to gradually release the stored water throughout the hot and arid months of summer.

Although the Wood River Land Trust has not yet catalogued the increasing species diversity in Elkhorn Creek, the slow process is certainly occurring, Frenzl said.

"It’s sort of a successional process. What we’re seeing is an increase of diversity, because there’s more water."

When the Elkhorn Creek project was conceived, a timeline was established for the gradual transfer of most of the creek’s flows to the historic channel.

For the last three years, high spring runoff flows were diverted into the original stream channel while normal flows continued down the irrigation ditch. Beginning this year, the opposite was planned to occur, but Frenzl said the exact timing of the transfer is dependent on a number of variables, including fish spawning seasons.

Boettger maintains the project was unique and worth the effort.

"That’s what’s rare about this project," Boettger said three years ago as he watched water gradually overtake the sagebrush in its path. "With the subtlest of touches, we’re recreating the natural process."

 

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