Department of Ecology News Release - July 7, 2014

Harmless dye test set for 3 Cowlitz Co. creeks
Understanding creek health for salmon recovery

LONGVIEW – Weather permitting, scientists from the state Department of Ecology will release a harmless red-orange, fluorescent dye into Germany, Mill and Abernathy creeks, west of Longview, sometime during the weeks of July 7 and 14.

The harmless dye called Rhodamine WT helps state researchers measure the speed of water through a section of a stream.

At the low concentrations used for the study, the dye doesn’t affect humans, fish or wildlife, and dissipates quickly. The effort is funded by the state Salmon Recovery Funding Board.

“The tests help tell us if our efforts to restore these creeks for salmon are working,” said Stephanie Estrella, a scientist with Ecology’s Environmental Assessment Program, who will be conducting the work.

The creeks are tributaries to the Lower Columbia River. They receive intensive monitoring as part of several experimental, watershed-scale evaluations to help environmental scientists better understand how salmon and trout respond to the latest approaches to restore habitat. These improvements include adding shade, woody debris and protecting natural streamside areas.

Ecology has received permission to access the sampling sites.

Researchers will track the dye plume with fluorometers that measure dye concentration in the water. Tracking the speed of the dye from upstream to downstream helps researchers calculate how long it takes for water to travel through that section of stream. The information will be incorporated into calculations so scientists better understand the creek’s overall water quality.

This short video from the Little Spokane River shows what the dye test looks like.



Sandy Howard, communications, 360-407-6408, @ecologyWA