Washington State Department of Ecology - August 2, 2013


Little Spokane River turning red for science

SPOKANE – Scientists from the Washington Department of Ecology (Ecology) will use a harmless fluorescent dye to track how fast water travels through the Little Spokane River as part of a larger effort to study dissolved oxygen and pH in the water this summer.

“If residents see a reddish fluorescent tint in the creek during either the week of August 5 or August 12, they needn’t worry,” said Scott Tarbutton, an environmental scientist for Ecology. Tarbutton added “Using dye for this type of study is very common, and research has long shown that the dye does not affect human health or aquatic life in any way at the low concentrations we use.”

Researchers will track the dye plume with an instrument able to detect the dye in the river.

“This study is part of our effort to understand the causes of low dissolved oxygen and high pH in the stream” said Elaine Snouwaert, who is coordinating Ecology’s water quality improvement plans for the Little Spokane River watershed.

The information will be used in computer models to help scientists understand the river’s water quality problems.

Parts of the Little Spokane River and several of its tributaries do not meet water quality standards for dissolved oxygen and pH endangering fish and other aquatic life. Nutrients and sunlight contribute to conditions creating excessive weeds and algae growth that cause oxygen and pH problems. Low flow levels can make these problems worse.

The Little Spokane River and its tributaries also fail water quality standards for bacteria, temperature and turbidity. In early 2012, Ecology published a draft plan to address these problems. The plan was approved by the U.S. Environmental Protection Agency in April 2012.

To see what the dye looks like view this short YouTube video from a 2009 Hangman Creek study.


Media Contact:

Brook Beeler, communication manager,@ecyspokane (Twitter), 509-329-3478, brook.beeler@ecy.wa.gov

For more information:

Little Spokane River water quality improvement projects (www.ecy.wa.gov/programs/wq/tmdl/littlespokane/index.html)

Ecology's social media (www.ecy.wa.gov/about/socialmedia.html)