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Tips

Summary: Seattle Public Utilities (SPU) has limited options and restrictive requirements for allowing property owners, builders and developers to construct new and/or modify existing structures over an existing public sewer and/or storm drain mainline through a build-over agreement. This is due to the long term obligations SPU has to its stakeholders toward repairing, maintaining and upgrading the City of Seattle’s public sewer and storm drainage mainline infrastructure.

Date Revised: 02/03/2023

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