SPOKANE, Wash. — Don’t be alarmed if you see bright red water flowing through the Spokane River on Tuesday.
The Spokane County Regional Water Reclamation Facility (SCRWRF) will conduct the dye tracer test on Aug. 5, from 11 a.m. to 3 p.m. using Rhodamine WT, an environmentally safe red dye added to treated wastewater before it enters the river.
SCRWRF said the test fulfills requirements under the facility’s National Pollutant Discharge Elimination System permit issued by the Washington State Department of Ecology. Water specialists will use the dye to study how treated wastewater mixes with river water and interactions with the Spokane Valley-Rathdrum Prairie Aquifer.
Researchers will use boats to collect water samples at various locations and depths. A drone will capture aerial footage of the mixing process.
According to SCRWRF, the red dye will be most visible at the intersection of North Havana Street and East Upriver Drive, near Spokane Community College. It will remain visible up to a half-mile downstream during the four-hour test.
Residents may notice the red coloration but should not be alarmed, as the dye poses no environmental or health risks.
For more information, visit spokanecounty.org.
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