Holiday closure Monday May 28: Most county offices will be closed in observance of Memorial Day.
For questions about the Duwamish Waterway Programs, please contact Doug Marsano. 

Wastewater Treatment Division
King Street Center
201 S. Jackson St., Suite 505
Seattle, WA 98104-3855

Get Directions to our office location in Seattle, Washington.
The Duwamish Waterway... running towards a brighter future

Tool kit

Important dates

Process Timeline
LDWG formed 2000
Initial Assessments 2000-2003

Draft Remedial Investigation

  • Nature and extent of contamination
  • Associated ecological and human health risks
 2003-2010

Draft Feasibility Study

  • Cleanup objectives identified
  • Cleanup alternatives evaluated
 2007-2011
Proposed Plan (EPA) 2011-2012
Record of Decision (EPA) 2012-2013
Allocation of Costs 2011-2014
Early Action Projects (committed to prior to Superfund listing) 2013
Additional Cleanup 2014-2030