The City of Sumner authorized the preparation of the Comprehensive Sewer Plan Amendment in accordance with WAC 173-240-050 as administered by the State of Washington Department of Ecology. This plan updates the previous Comprehensive Sewer Plan prepared by Parametrix, Inc. in November 1989.

Since preparation of the 1989 Comprehensive Sewer Plan, the City of Sumner has experienced major demographic changes that affect the City’s wastewater collection system, including:
• Reduction of the total Urban Growth Area (UGA).
• Increased industrial development along 142nd Avenue East.
• Amendment to the Comprehensive Land Use Plan.
• Increase in City growth pattern predicted at 3.5 percent per year.
It is the intent of this document to analyze the City’s collection system and to identify system deficiencies for existing and future flow conditions. If any deficiencies are identified in the City’s collection system, improvement and cost recommendations will be developed.