SPOKANE COUNTY, Wash. – Spokane County environmental officials conducted water quality testing Tuesday using red dye in the Spokane River to better understand how treated wastewater affects the waterway.
Red dye was added to the treated wastewater at the Spokane County Regional Water Reclamation Facility. Once that wastewater flows to the Spokane River, the dye shows how the two waters mix, and that’s what scientists want to track.
“Where does it mix in and how fast does it mix. What zones are going to be impacted the most before it’s fully diluted?” said Hannah Thomascall, Water Reclamation Project manager.
From there, scientists are able to see how the treated wastewater impacts certain parts of the river.
“They’ll look at this and see if there’s any harmful impacts they might be having, especially in those acute mixing zones for things like plant life that lives here and fish,” Thomascall said.
These results go to the Department of Ecology and determine if the wastewater is clean enough to continue to be dumped into the river.
“That tells us what we can discharge into the river as far as nutrients, pollutants, metals, things like that,” Thomascall said.
This is the second time in 15 years that the Spokane County Regional Water Reclamation Facility has done this study.
Melinda Martin, who lives in Spokane County, was among those who observed the testing.
“It’s fascinating watching it kind of like disperse out and just watching how the river absorbs things,” Martin said.
The dye used is not harmful to people, plants or animals that use the river. Scientists say this study will make the river cleaner.
“I’m absolutely for it. I think clean water is 100% important for our community. And I’m just 100% in support of making sure that we have a healthy environment,” Martin said.
This dye dilutes from the water just a few hours after it is added. The results of this study will be available in the coming months.
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