PHOTOS: See inside the new stormwater tank in downtown Spokane

SPOKANE, Wash.– On Monday, the city marked the completion of the final combined sewer overflow (CSO) tank that is part of a network of more than two dozen tanks designed to alleviate flooding and prevent tainted water from entering the Spokane River.

This final addition is the second largest tank in the system, but it will be the most active, according to City of Spokane Director of Engineering Services Kyle Twohig. The tank is located behind the downtown library, underneath the new plaza on Spokane Falls Boulevard. The CSO 26 tank can hold 2.2 million gallons of wastewater.

“The river is just, it’s our backbone. This is what we live on,” Twohig said. “It’s just so exciting to do something that’s going to improve the health of this river for generations.”

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