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Puget Sound shoreline next to the West Point Treatment Plant, Seattle

Puget Sound Beach CSO Control projects

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South Magnolia CSO Control Engineering Report (Facility Plan)

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Engineering Report (Facility Plan) for South Magnolia CSO Control Facility, Draft, December 2010This Engineering Report (Facility Plan) outlines improvements to the King County conveyance system serving the South Magnolia Basin that are necessary to control CSOs in compliance with RCW 90.48.480 and WAC 173-245-020 (22).

This report is submitted in compliance with the first of three compliance schedule dates noted in Section S18 of the West Point Treatment Plant National Pollutant Discharge Elimination System Permit (refer to page 53 of permit).

Final Engineering Report (Facility Plan), September 2011

Draft Engineering Report (Facility Plan), December 2010

Project links

This project was initiated to address the following:

  • Revised Code of Washington (RCW) 90.48.480: This law requires “the greatest reasonable reduction of combined sewer overflows.”
  • Washington Administrative Code (WAC) 173-245-020 (22): “The greatest reasonable reduction’ means control of each CSO in such a way that an average of one untreated discharge may occur per year.”