The city of Spokane has sent out for rebid the contract for a projected $3.7 million combined sewer overflow tank to be built on east Sprague Avenue near the Hamilton overpass, says city spokeswoman Marlene Feist. 

The project was sent out for rebid because one of the contractors contested the results, and the city found enough irregularities with the bid to warrant a rebid, Feist says. Construction is set to begin in early fall, she says, and should be completed in about a year. 

“The tank will hold combined stormwater and sanitary sewage overflow during storms, when the systems can become overwhelmed, so that water doesn’t go into the river,” Feist says. 

Its maximum capacity is expected to be about 300,000 gallons. 

The city of Spokane provided the engineering services for the project, and the city’s wastewater department is providing funding for it, Feist says. 

The tank is part of the city’s larger integrated clean water plan, which aims to manage better waste and storm water runoff and to reduce the amount of pollutants entering waterways, in accordance with the federal Clean Water Act. 

The city of Spokane must substantially reduce its combined sewer and stormwater runoff by the end of 2017, as mandated by the U.S. Environmental Protection Agency and Washington State Department of Ecology. The city began last year its about $300 million plan for projects during the next five years to bring the area’s runoff in line with the mandates.

Projects will include 11 combined sewer overflow tanks, not including a 1.5 million gallon tank under construction at Underhill Park or a 1 million gallon basin at 21st Avenue and Ray Street. The city’s plan also includes more stormwater drainage and an additional level of treatment at the Riverside Park Water Reclamation Facility.