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Reports and Regulations

Seattle must meet state and federal regulatory requirements in order to comply with the Clean Water Act. The program is regulated via National Pollutant Discharge Elimination System (NPDES) permits.

2010-2015 NPDES Combined Sewer System Permit Fact Sheet (pdf)
2010-2015 NPDES Combined Sewer System Permit (pdf)

One requirement in the current permit is to provide realtime online reporting of overflows in Seattle.

Annual status reports




Modeling reports

Volume 1 - Final Flow Monitoring Summary Report Executive Summary (pdf)

Monitoring reports

Long-Term Control Plan Hydraulic Model Report

Volume 2 - Flow Monitoring Plan 2008-2009

Volume 3 - Flow Monitoring Plan 2009-2010

Volume 4 - Final Phase 1 Flow Monitoring Report

Volume 5 - Final Phases 2 and 3 Flow Monitoring Report