Final SD Model BMP Design Manual Appendices

329 Pages·2015·12.29 MB·English

Table of Contents
Appendix A Submittal Templates ...................................................................................... A-1
A.1 Standard SWQMP ........................................................................................................................................... A-2
A.2 PDP SWQMP................................................................................................................................................... A-3
Appendix B Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods ..
..................................................................................................................... B-1
B.1 DCV .................................................................................................................................................... B-2
B.1.1 Runoff Factor ............................................................................................................................................ B-2
B.1.2 Offline BMPs ............................................................................................................................................ B-3
B.1.3 85th Percentile, 24-Hour Storm Event ................................................................................................. B-3
B.2 Adjustments to Account for Site Design BMPs ......................................................................................... B-6
B.2.1 Adjustment to Impervious Runoff Factor ........................................................................................... B-6
B.2.2 Adjustment to DCV ................................................................................................................................. B-8
B.3 Harvest and Use BMPs ................................................................................................................................. B-11
B.3.1 Planning Level Harvest and Use Feasibility ....................................................................................... B-11
B.3.2 Harvested Water Demand Calculation ............................................................................................... B-13
B.3.3 Sizing Harvest and Use BMPs .............................................................................................................. B-17
B.4 Infiltration BMPs ........................................................................................................................................... B-18
B.4.1 Simple Method ........................................................................................................................................ B-19
B.4.2 Percent Capture Method ....................................................................................................................... B-20
B.4.3 Technical Basis for Equivalent Sizing Methods ................................................................................ B-24
B.5 Biofiltration BMPs ......................................................................................................................................... B-26
B.5.1 Standard Biofiltration BMP Footprint Sizing Factors ...................................................................... B-28
B.5.2 Basis for Minimum Sizing Factor for Biofiltration BMPs ............................................................... B-29
B.6 Flow-Thru Treatment Control BMPs (for use with Alternative Compliance) .................................... B-33
B.6.1 PDP Most Significant Pollutants of Concern .................................................................................... B-33
B.6.2 Selection of Flow-Thru Treatment Control BMPs ........................................................................... B-36
B.6.3 Sizing Flow-Thru Treatment Control BMPs: .................................................................................... B-44
Appendix C Geotechnical and Groundwater Investigation Requirements ....................... C-1
C.1 Purpose and Phasing ....................................................................................................................................... C-1
C.2 Geotechnical Feasibility Criteria .................................................................................................................... C-2
C.2.1 Soil and Geologic Conditions ................................................................................................................. C-2

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C.2.2 Settlement and Volume Change ............................................................................................................. C-3
C.2.3 Slope Stability ............................................................................................................................................ C-3
C.2.4 Utility Considerations .............................................................................................................................. C-3
C.2.5 Groundwater Mounding ......................................................................................................................... C-4
C.2.6 Retaining Walls and Foundations .......................................................................................................... C-4
C.2.7 Other Factors ............................................................................................................................................ C-4
C.3 Groundwater Quality and Water Balance Feasibility Criteria ................................................................... C-5
C.3.1 Soil and Groundwater Contamination .................................................................................................. C-5
C.3.2 Separation to Seasonal High Groundwater .......................................................................................... C-5
C.3.3 Wellhead Protection ................................................................................................................................. C-5
C.3.4 Contamination Risks from Land Use Activities .................................................................................. C-6
C.3.5 Consultation with Applicable Groundwater Agencies ....................................................................... C-6
C.3.6 Water Balance Impacts on Stream Flow............................................................................................... C-6
C.3.7 Downstream Water Rights ...................................................................................................................... C-7
C.3.8 Other Factors ............................................................................................................................................ C-7
C.4 Geotechnical and Groundwater Investigation Report Requirements ..................................................... C-7
C.4.1 Site Evaluation .......................................................................................................................................... C-7
C.4.2 Field Investigation .................................................................................................................................... C-8
C.4.3 Reporting Requirements by Geotechnical Engineer .......................................................................... C-8
C.4.4 Reporting Requirements by the Project Design Engineer ............................................................... C-10
C.5 Feasibility Screening Exhibits ...................................................................................................................... C-15
Appendix D Approved Infiltration Rate Assessment Methods for Selection and Design of
Storm Water BMPs ......................................................................................... D-1
D.1 Introduction ................................................................................................................................................... D-1
D.2 Role of Infiltration Testing in Different Stages of Project Development ............................................. D-1
D.3 Guidance for Selecting Infiltration Testing Methods ............................................................................... D-2
D.3.1 Desktop Approaches and Data Correlation Methods ....................................................................... D-4
D.3.2 Surface and Shallow Excavation Methods .......................................................................................... D-5
D.3.3 Deeper Subsurface Tests ........................................................................................................................ D-8
D.4 Specific Considerations for Infiltration Testing ....................................................................................... D-10
D.4.1 Hydraulic Conductivity versus Infiltration Rate versus Percolation Rate .................................... D-10
D.4.2 Cut and Fill Conditions ........................................................................................................................ D-10
D.4.3 Effects of Direct and Incidental Compaction .................................................................................. D-12

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D.4.4 Temperature Effects on Infiltration Rate .......................................................................................... D-12
D.4.5 Number of Infiltration Tests Needed ................................................................................................ D-13
D.5 Selecting a Safety Factor .............................................................................................................................. D-13
D.5.1 Determining Factor of Safety .............................................................................................................. D-14
D.5.2 Site Suitability Considerations for Selection of an Infiltration Factor of Safety ......................... D-15
D.5.3 Design Related Considerations for Selection of an Infiltration Factor of Safety ....................... D-16
D.5.4 Implications of a Factor of Safety in BMP Feasibility and Design ............................................... D-18
Appendix E BMP Design Fact Sheets ................................................................................ E-1
E.1 Source Control BMP Requirements ............................................................................................................. E-2
E.2 SD-1 Street Trees ........................................................................................................................................... E-15
E.3 SD-5 Impervious Area Dispersion.............................................................................................................. E-19
E.4 SD-6A: Green Roofs ..................................................................................................................................... E-23
E.5 SD-6B Permeable Pavement (Site Design BMP)...................................................................................... E-27
E.6 SD-8 Rain Barrels .......................................................................................................................................... E-28
E.7 HU-1 Cistern .................................................................................................................................................. E-29
E.8 INF-1 Infiltration Basin ................................................................................................................................ E-33
E.9 INF-2 Bioretention ........................................................................................................................................ E-38
E.10 INF-3 Permeable Pavement (Pollutant Control) ...................................................................................... E-46
E.11 PR-1 Biofiltration with Partial Retention ................................................................................................... E-54
E.12 BF-1 Biofiltration ........................................................................................................................................... E-62
E.13 BF-2 Nutrient Sensitive Media Design ....................................................................................................... E-70
E.14 BF-3 Proprietary Biofiltration Systems ...................................................................................................... E-73
E.15 FT-1 Vegetated Swales .................................................................................................................................. E-74
E.16 FT-2 Media Filters ......................................................................................................................................... E-80
E.17 FT-3 Sand Filters ........................................................................................................................................... E-83
E.18 FT-4 Dry Extended Detention Basin ......................................................................................................... E-89
E.19 FT-5 Proprietary Flow-Thru Treatment Control BMPs ......................................................................... E-94
E.20 PL Plant List .................................................................................................................................................. E-95
Appendix F Biofiltration Standard and Checklist .............................................................. F-1
F.1 Pollutant Treatment Performance Standard ................................................................................................ F-8
F.2 Guidance on Sizing and Design of Non-Standard Biofiltration BMPs ................................................ F-11
F.2.1 Guidance on Design per Conditions of Certification/Verification ............................................... F-11
F.2.2 Sizing of Flow-Based Biofiltration BMP ............................................................................................ F-12

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Appendix G Guidance for Continuous Simulation and Hydromodification Management
Sizing Factors ................................................................................................. G-1
G.1 Guidance for Continuous Simulation Hydrologic Modeling for Hydromodification Management
Studies in San Diego County Region 9 ....................................................................................................... G-1
G.1.1 Introduction G-1
G.1.2 Software for Continuous Simulation Hydrologic Modeling ............................................................. G-1
G.1.3 Climatology Parameters .......................................................................................................................... G-2
G.1.4 LAND CHARACTERISTICS AND LOSS PARAMETERS ........................................................ G-7
G.1.5 MODELING STRUCTURAL BMPS (PONDS AND LID FEATURES) ............................... G-13
G.1.6 FLOW FREQUENCY AND DURATION .................................................................................... G-18
G.2 Sizing Factors for Hydromodification Management BMPs ................................................................... G-21
G.2.1 Unit Runoff Ratios ................................................................................................................................ G-25
G.2.2 Sizing Factors for "Infiltration" BMP ................................................................................................ G-27
G.2.3 Sizing Factors for Bioretention ........................................................................................................... G-32
G.2.4 Sizing Factors for Biofiltration with Partial Retention and Biofiltration...................................... G-37
G.2.5 Sizing Factors for Biofiltration with Impermeable Liner ................................................................ G-43
G.2.6 Sizing Factors for "Cistern" BMP ....................................................................................................... G-49
Appendix H Guidance for Investigating Potential Critical Coarse Sediment Yield Areas H-1
H.1 Criteria for GLU Analysis.............................................................................................................................. H-3
H.2 Optional Additional Analysis When Potential Critical Coarse Sediment Yield Areas are Present
Onsite H-18
Appendix I Forms and Checklists ...................................................................................... I-1
Glossary of Key Terms ............................................................................................................... i

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M ODE L BM P DE S I G N M A N UAL

Appendix

A
Submittal Templates

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Appendix A: Submittal Templates
Appendix A Submittal Templates
The following templates were developed to assist the project applicant and the plan reviewer:
• Standard SWQMP
• PDP SWQMP

A-1 June 2015
Appendix A: Submittal Templates
A.1 Standard SWQMP

Place holder for jurisdiction specific guidance.

A-2 June 2015
Appendix A: Submittal Templates
A.2 PDP SWQMP

Place holder for jurisdiction specific guidance.

A-3 June 2015
M ODE L BM P DE S I G N M A N UAL
Appendix

B
Storm Water Pollutant Control
Hydrologic Calculations and Sizing
Methods

June 2015