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Long-Term Control Plan

The Plan to Protect Seattle's Waterways

In 2012, 154 million gallons of untreated sewage and stormwater flowed into our lakes, creeks, and Puget Sound. Seattle Public Utilities is preparing a long-range plan that will create a comprehensive strategy to reduce these Combined Sewer Overflows (CSOs). The plan will:

  • Identify areas of Seattle where CSO reduction projects are required
  • Evaluate solutions for reducing CSOs in affected areas
  • Select a preferred alternative for each affected area
  • Recommend a schedule for designing and constructing projects from 2016-2025

SPU is preparing a programmatic Environmental Impact Statement (EIS) to identify potential impacts to people and the environment. Scoping was conducted in 2011 to determine the range or “scope” of issues to study in the EIS. Since then, federal and state regulators have provided SPU with the option of developing a new approach to the plan that addresses both sewage overflows and stormwater discharges, so there is a new scoping effort underway for the EIS.

View the following to learn more about the plan and provide feedback:

How to Provide Input
May 20 – June 20, 2013

  • Online:
    Watch the video overview of the Plan and complete a short survey at the end.
  • Mail or email:
    Betty Meyer
    betty.meyer@seattle.gov
    Seattle Public Utilities, Suite 4900
    P.O. Box 34018
    Seattle, WA  98124-4018
  • In person:
    Attend a scoping open house.
    Monday, June 3, 2013
    4:30-6:30 p.m.
    Seattle City Hall, Bertha Knight Landes Room
    600 4th Avenue, Seattle

Background of Long-Term Control Plan (LTCP)

View the timeline for the LTCP (pdf)

LTCP Glossary of Terms (pdf)

In 2010 the Sounding Board was formed to guide the development of the LTCP. Sounding Board members were recruited from throughout the city to provide a diverse set of perspectives. They considered input from their colleagues and neighbors, as well as staff recommendations, to provide constructive advice about important investment decisions.

Sounding Board members:

  • Developed an understanding of the data and rationale for projects,
  • Assisted in developing and applying criteria to make decisions about the best alternatives,
  • Reviewed and commented on the elements of the LTCP, and
  • Provided guidance on public involvement activities and communications

More Information