Combined Sewer System Long Term Control Plan - DC Water

Table of Contents
LIST OF TABLES
Table No. Title of Table Page No.
4-2 CSS and SSWS Monitoring Sites..................................................................... 4-6
4-3 Summary of CSS and SSWS Sampling ........................................................... 4-7
4-4 Event Mean Concentrations ............................................................................. 4-9
4-5 Detected Priority Pollutant Parameters............................................................ 4-10
4-6 Summary of Metals Sampling.......................................................................... 4-11
4-7 Summary of 97 th Percentile Daily Values for Metals at Monitored CSO and
Storm Water Outfalls ....................................................................................... 4-12
4-8 Results of Mixing Zone Analysis for CSO 021/ Potomac River as
Compared To DOH WQS ................................................................................ 4-12
4-9 BLM Calculated CMCs for Dissolved Copper ................................................ 4-13
4-10 Average Annual Flows..................................................................................... 4-17
4-11 Diurnal Dry Weather Flow Factors.................................................................. 4-18
4-12 Wet Weather Peaking Factors for Dry Weather Flow...................................... 4-19
4-13 Calibration Results........................................................................................... 4-20
5-1 Parameters for Receiving Water Monitoring ................................................... 5-3
5-2 Receiving Water Boundary Conditions – Event Mean Concentrations........... 5-6
5-3 Event Mean Concentrations for Streams and Other Permitted Discharges ..... 5-7
5-4 Monthly Dissolved Oxygen Event Mean Concentrations at Boundaries......... 5-7
5-5 Flow Varying Event Mean Concentrations for the Potomac River Boundary. 5-8
6-1 Annual CSO Overflow Predictions for Average Year ..................................... 6-2
6-2 Annual CSO Overflow Prediction for Average Year....................................... 6-2
6-3 Source of Pollutant Loads to Anacostia River Within District ........................ 6-4
6-4 Source of Pollutant Loads to Rock Creek Within District............................... 6-6
6-5 Source of Pollutant Loads to Potomac River Within District .......................... 6-7
7-1 Assessment of CSO Control Technologies ...................................................... 7-2
7-2 Comparison of Solids and Floatables Control Technologies........................... 7-27
7-3 Screening of CSO Control Technologies......................................................... 7-28
8-1 Existing Inflatable Dams.................................................................................. 5-9
8-2 Groundwater Diversion Projects...................................................................... 8-13
8-3 Orphan Storm Sewer Separation Project Summary......................................... 8-14
8-4 U.S. Soldier’s and Airman’s Home Project Summary..................................... 8-15
8-5 Areas Treated by LID-R................................................................................... 8-16
8-6 Application Rates used for Low Impact Development – Retrofit.................... 8-16
8-7 Anacostia River Tunnel Alternatives............................................................... 8-21
8-8 Load Comparison: Separation vs. CSO Control .............................................. 8-25
8-9 Performance of Preliminary CSO Control Alternatives................................... 8-29
8-10 Comparison of Preliminary Control Plan Alternatives .................................... 8-31
9-1 Anacostia River Final Alternatives .................................................................. 9-7
9-2 Facility Sizing: Anacostia River Final Alternatives......................................... 9-13
J:\1160\LTCP\LTCP Final\toc.doc vii FINAL - July 2002