CSO Long Term Control Plan II Long Term Control Plan Flushing Bay TABLE OF CONTENTS EXECUTIVE SUMMARY ...................................................................................................... ES-1 1.0 INTRODUCTION ..........................................................................................................1-1 1.1 Goal Statement ................................................................................................................ 1-1 1.2 Regulatory Requirements (Federal, State, Local) ........................................................... 1-2 1.3 LTCP Planning Approach ................................................................................................ 1-3 2.0 WATERSHED/WATERBODY CHARACTERISTICS ...................................................2-1 2.1 Watershed Characteristics ............................................................................................... 2-1 2.2 Waterbody Characteristics ............................................................................................. 2-33 3.0 CSO BEST MANAGEMENT PRACTICES ...................................................................3-1 3.1 Collection System Maintenance and Inspection Program ............................................... 3-3 3.2 Maximizing Use of Collection System for Storage ........................................................... 3-3 3.3 Maximizing Wet Weather Flow to WWTPs ...................................................................... 3-4 3.4 Wet Weather Operating Plan ........................................................................................... 3-4 3.5 Prohibition of Dry Weather Overflows .............................................................................. 3-5 3.6 Industrial Pretreatment Program ...................................................................................... 3-5 3.7 Control of Floatables and Settleable Solids ..................................................................... 3-6 3.8 Combined Sewer Replacement ....................................................................................... 3-6 3.9 Combined Sewer Extension ............................................................................................. 3-7 3.10 Sewer Connection & Extension Prohibitions ................................................................... 3-7 3.11 Septage and Hauled Waste ............................................................................................. 3-7 3.12 Control of Runoff .............................................................................................................. 3-7 3.13 Public Notification ............................................................................................................. 3-8 3.14 Characterization and Monitoring ...................................................................................... 3-8 3.15 CSO BMP Report Summaries ......................................................................................... 3-8 4.0 GREY INFRASTRUCTURE .........................................................................................4-1 4.1 Status of Grey Infrastructure Projects Recommended in Facility Plans .......................... 4-1 4.2 Other Water Quality Improvement Measures Recommended in Facility Plans (Dredging, Floatables, Aeration) ...................................................................................... 4-4 4.3 Post-Construction Monitoring ........................................................................................... 4-4 5.0 GREEN INFRASTRUCTURE .......................................................................................5-1 5.1 NYC Green Infrastructure Plan (GI Plan)......................................................................... 5-1 5.2 Citywide Coordination and Implementation ..................................................................... 5-1 5.3 Completed Green Infrastructure to Reduce CSOs (Citywide and Watershed) ............... 5-2 5.4 Future Green Infrastructure in the Watershed ................................................................. 5-4 6.0 BASELINE CONDITIONS AND PERFORMANCE GAP ..............................................6-1 6.1 Define Baseline Conditions .............................................................................................. 6-1 6.2 Baseline Conditions – Projected CSO Volumes and Loadings after the Facility Plan and GI Plan .............................................................................................................. 6-5 6.3 Performance Gap ............................................................................................................. 6-9 Submittal: December 29, 2016 i with CSO Long Term Control Plan II Long Term Control Plan Flushing Bay 7.0 PUBLIC PARTICIPATION AND AGENCY COORDINATION ......................................7-1 7.1 Local Stakeholder Team .................................................................................................. 7-1 7.2 Summaries of Stakeholder Meetings ............................................................................... 7-1 7.3 Coordination with Highest Attainable Use ....................................................................... 7-5 7.4 Internet Accessible Information Outreach and Inquiries .................................................. 7-5 8.0 EVALUATION OF ALTERNATIVES ............................................................................8-1 8.1 Considerations for LTCP Alternatives Under the Federal CSO Policy ............................ 8-1 8.2 Matrix of Potential CSO Reduction Alternatives to Close Performance Gap from Baseline ................................................................................................................. 8-15 8.3 CSO Reductions and Water Quality Impact of Retained Alternatives ........................... 8-53 8.4 Cost Estimates for Retained Alternatives ...................................................................... 8-59 8.5 Cost-Attainment Curves for Retained Alternatives ........................................................ 8-62 8.6 Use Attainability Analysis ............................................................................................... 8-87 8.7 Water Quality Goals ....................................................................................................... 8-90 8.8 Recommended LTCP Elements to Meet Water Quality Goals ...................................... 8-91 9.0 LONG-TERM CSO CONTROL PLAN IMPLEMENTATION .........................................9-1 9.1 Adaptive Management (Phased Implementation) ............................................................ 9-1 9.2 Implementation Schedule ................................................................................................ 9-1 9.3 Operational Plan/O&M (Operation and Maintenance) ..................................................... 9-2 9.4 Projected Water Quality Improvements ........................................................................... 9-2 9.5 Post Construction Monitoring Plan and Program Reassessment .................................... 9-2 9.6 Consistency with Federal CSO Policy ............................................................................. 9-3 9.7 Compliance with Water Quality Goals ........................................................................... 9-37 10.0 REFERENCES ........................................................................................................... 10-1 11.0 GLOSSARY ............................................................................................................... 11-1 APPENDICES Appendix A: Supplemental Tables Appendix B: Public Meeting Materials Submittal: December 29, 2016 ii with CSO Long Term Control Plan II Long Term Control Plan Flushing Bay LIST OF TABLES Table ES-1. Classifications and Standards Applied .............................................................................. ES-3 Table ES-2. CSO Discharges Tributary to Flushing Bay (2008 Typical Year) ...................................... ES-4 Table ES-3. Model Calculated 2008 Baseline Fecal Coliform Maximum Monthly GM and Attainment of Existing WQ Criteria .................................................................................................... ES-15 Table ES-4. Model Calculated Baseline DO Attainment – Existing WQ Criteria (2008)...................... ES-15 Table ES-5. Comparison of the Model Calculated 2008 Baseline and 100% Flushing Bay CSO Control Fecal Coliform Maximum Monthly GM ................................................................ ES-16 Table ES-6. Model Calculated 2008 Baseline and 100% CSO Control DO Attainment of Class SC WQ Criteria ...................................................................................................................... ES-17 Table ES-7. Model Calculated 2008 Baseline Enterococci Maximum 30-day GM and Attainment of Potential Future Primary Contact Water Quality Criteria ................................................. ES-18 Table ES-8. Model Calculated 2008 100% CSO Control Enterococci Maximum 30-day GM and Attainment of Potential Future Primary Contact WQ Criteria .......................................... ES-19 Table ES-9. Retained Alternatives ....................................................................................................... ES-20 Table ES-10. Flushing Bay Retained Alternatives Summary (2008 Rainfall) ....................................... ES-21 Table ES-11. Cost of