Spokane Combined Sewer Overflow

Since 1998, CTE has provided management and technical leadership to the Spokane CSO Reduction Program.  Although the area receives only about 16 inches of annual precipitation, resultant CSO's are in conflict with existing state requirements limiting such occurrences to one per structure per year - much more restrictive than national guidelines.  Our efforts have involved system definition and modeling, coordinating water quality information, developing alternatives and costs, and facilitating the alternative selection process.  In addition, we have designed and put into operation a "linear" storage unit to address overflows from structures near the treatment plant.