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Reports and Regulations

Seattle must meet state and federal regulatory requirements in order to comply with the Clean Water Act. Seattle developed a 2010 CSO Reduction Plan Amendment (pdf) to describe the effort to reduce CSOs.

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.

Status Report

2012 3rd Quarter Progress Report (pdf)

2011 Annual Progress Report (pdf)

Overflow Reports

The permit also requires monthly and annual reports of overflows in Seattle. All documents are in PDF format.

2014 Monthly Reports

October

September

August

July

June

May

April

March

February

January

Annual Reports

2013

2012

2011

2010

2009

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