"With billions of dollars at stake, local and state officials around the country are questioning the cost and benefit of continued work to control combined sewer overflow (CSO), including here in Seattle, where more than $1.2 billion in ratepayer dollars are on the table."
"King County has outlines of a control plan to limit pollution from overflows of small amounts of raw sewage from some storm drains during heavy rain. CSO work has been under way in Seattle and King County for decades, and pollution from overflows already is greatly reduced.
But getting the last percentages of control is very expensive. It's so expensive that it could siphon off the region's capacity to do other environmental work, local officials say, even though study after study has shown stormwater runoff, not the remaining volume of combined sewer overflows, is the largest source of pollution to Puget Sound."