Stormwater Management Standards Manual 2008 …

1 1 Third Edition Stormwater Standards Manual September 2008 Page 2 TMACOG Stormwater Management Standards Manual THIRD EDITION SEPTEMBER 2008 ACKNOWLEDGMENTS Thank you to the members of the Stormwater Action Group for their dedication and hard work in preparing this Manual , and in particular to Jason Sisco of the Wood County Engineer s Office, Marcus Ricci of the Lucas Soil and Water Conservation District, and Travis Andres, TMACOG intern and University of Toledo Graduate Student. This document was prepared with funding from members of the TMACOG Stormwater Coalition. Cover image: Image Science and Analysis Laboratory, NASA Johnson Space Center 10 July 2006. Astronaut Photography of Earth Display Record.: Edition Stormwater Standards Manual September 2008 Page 3 TABLE OF CONTENTS FIGURES ..14 TABLES.

2 15 EXECUTIVE SUMMARY ..16 CHAPTER 1 - CHAPTER PURPOSE OF THE Manual AND REVISION IMPACTS OF DEVELOPMENT ON WATER Changes in Watershed Hydrology ..22 Changes in Stream Morphology ..22 IMPACTS OF DEVELOPMENT ON WATER FRAMEWORK FOR DESIGN OF Stormwater Management Nonstructural Controls ..26 Structural Controls ..26 CHAPTER 2 Stormwater Management SUBMITTAL CHAPTER DEFINITIONS OF DISTURBANCE, CONSTRUCTION ACTIVITY, AND Disturbance: ..28 Construction Activity: ..28 Development: ..29 EXEMPTIONS FROM THESE DISTURBANCE IN FLOODPLAINS, FLOODWAYS OR SITE PLAN APPROVAL Submittal Requirements for Site Additional Submittal Requirements for Site Plans Greater than 100 Acres ..31 CONTACT INFORMATION FOR LOCAL CHAPTER 3 RUNOFF REDUCTION HIERARCHY AND PERFORMANCE CRITERIA FOR RUNOFF AND CHAPTER RUNOFF REDUCTION Non-Structural Controls.

3 39 Structural Controls ..40 RUNOFF Development of 100 acres or less ..42 Development greater than 100 acres ..45 Downstream Analysis ..46 CONTROL DRAINAGE Pumps ..47 Capacity ..48 Third Edition Stormwater Standards Manual September 2008 Page Drainage Structure Location ..49 Curb Inlets ..49 Pipe Criteria ..49 CHAPTER 4 - CONSTRUCTION SITE RUNOFF CONTROL ..51 CHAPTER PURPOSE AND Exclusions: Activities that are not Subject to Construction Site Runoff Control ..52 Conflicts, Severability, Nuisances and Responsibility ..52 APPLICATION Compliance with State and Federal DUTY TO INFORM CONTRACTORS AND DEVELOPMENT OF Stormwater POLLUTION PREVENTION PLANS (SWP3) ..53 Site Description and Site Map ..54 A Soils Engineering Report: ..55 PERFORMANCE Non-Structural Preservation Measures.

4 55 Erosion Control Stabilization ..56 Permanent Stabilization of Conveyance Channels ..57 RUNOFF CONTROL SEDIMENT CONTROL Timing ..57 Sediment Settling Silt Fence and Diversions ..58 Inlet Protection ..59 Off-Site Tracking of Sediment and Dust Control ..59 State Surface Water Modifying Controls ..60 NON-SEDIMENT POLLUTANT Waste Materials ..60 Concrete Truck Wash Fuel/Liquid Tank Storage ..61 Toxic or Hazardous Waste Contaminated Soils Disposal and Runoff ..61 COMPLIANCE WITH OTHER TRENCH AND GROUND WATER INTERNAL FINAL CHAPTER 5 - POST-CONSTRUCTION RUNOFF CONTROLS ..63 CHAPTER RUNOFF General Guidelines ..63 Grass RUNOFF Third Edition Stormwater Standards Manual September 2008 Page Filter Sand Filter.

5 67 RUNOFF Bioretention Cells ..74 Stormwater Wetland ..87 Wet Detention Ponds ..94 Dry Extended Detention Basins ..100 ADDITIONAL Stormwater Management BMPS..105 CHAPTER 6 ILLICIT DISCHAGE DETECTION AND CHAPTER THIS CHAPTER IS INTENDED TO PROVIDE GUIDANCE INTRODUCTION TO ILLICIT Types of Illicit Discharges ..106 Mode of Entry ..106 Why Are Illicit Discharge Detection and Elimination Efforts Necessary? ..107 PERMIT MAPPING, Outfall Reconnaissance Inventory (ORI) Materials ..108 Outfall Reconnaissance Inventory (ORI) Field PLAN TO DETECT & ELIMINATE ILLICIT Priority Areas ..109 Dry Weather Field Screening ..112 Tracing Procedures ..113 PUBLIC Local Agency Contact Information:..114 CHAPTER 7 - RIPARIAN SETBACKS ..116 CHAPTER Exclusions: Situations that are not Subject to Riparian Setbacks.

6 117 Conflicts, Severability, and Responsibility ..117 ESTABLISHMENT OF A RIPARIAN Adjustments for Slopes in Setback Areas ..118 Wetlands within Riparian Setback Area ..118 Identifying Setbacks on Required USES PERMITTED IN THE RIPARIAN USES PROHIBITED IN THE RIPARIAN Non-conforming Structures or Uses in the Riparian Setback ..120 BOUNDARY INTERPRETATION AND APPEALS VARIANCES WITHIN RIPARIAN INSPECTION OF RIPARIAN CHAPTER 8 - REGULATORY FLOODPLAIN AND CHAPTER LANDS SUBJECT TO THESE CONTROL Regulatory Floodplain ..124 Third Edition Stormwater Standards Manual September 2008 Page Regulatory PROHIBITED OPEN SPACE PERMITTED USES IF SPECIFICALLY ADDITIONAL PERFORMANCE Standards FOR THE REGULATORY CONSTRUCTION Development Proposals.

7 127 CHAPTER 9 - NATURAL WETLANDS PROTECTION ..129 CHAPTER WETLANDS IDENTIFICATION AND WETLANDS AUTHORITY AND GENERAL Antidegradation Rules ..133 Compensatory Mitigation ..133 OAK OPENINGS PLAN REVIEW CHAPTER 10 - INSPECTION AND PROHIBITION OF NON- Stormwater GUARANTEES FOR COMPLETION OF FACILITY ACCESS AND PENALTIES FOR APPENDIX A: GLOSSARY ..137 AH AO ACCELERATED SOIL APPROPRIATE BANKFULL BASE BASE FLOOD ELEVATION (BFE) ..138 BASE BEST Management PRACTICE (BMP) ..138 BUFFER STRIP/ BUFFER BUILDING CAPACITY (ADEQUATE DOWNSTREAM Stormwater CAPACITY) ..138 Third Edition Stormwater Standards Manual September 2008 Page 7 CATCH CHANNEL CHECK CONCENTRATED ANIMAL FEEDING OPERATION (CAFO) ..139 CRITICAL DAMAGED/DISEASED DEPRESSIONAL STORAGE DESIGN DETENTION DETENTION DISTURBED DRAINAGE DRAINAGE DRAINAGE AREA (ALSO SEE WATERSHED).

8 141 EARTH EROSION AND SEDIMENT EXCEPTIONAL FUNCTIONAL VALUE EXTENDED FINAL FINAL FIRST FLOODPLAIN (SEE REGULATORY FLOODPLAIN) ..142 FLOOD-PRONE FLOODWAY (SEE REGULATORY FLOODWAY)..142 FLOODWAY FLOW FLOW GEOTEXTILE GROUND Third Edition Stormwater Standards Manual September 2008 Page 8 GROUND WATER HAZARDOUS HYDRIC HYDROPHYTIC IMPERVIOUS INTENSITY-DURATION-FREQUENCY LAND LANDSCAPE LARGER COMMON PLAN OF LINEAR MANNING'S ROUGHNESS COEFFICIENT ("N") ..144 MITIGATION (SEE WETLAND MITIGATION) ..144 MULTI-FAMILY MAXIMUM EXTENT NGVD ..145 NPDES ..145 NATURAL NATIONWIDE PERMIT (NWP) ..145 NON-POINT SOURCE NON-STRUCTURAL NOXIOUS OFF-LINE BMP ..145 OFF-SITE OHIO EPA GENERAL CONSTRUCTION OHIO RAPID ASSESSMENT ONE HUNDRED YEAR FLOOD (100-YEAR FLOOD).

9 146 ONE HUNDRED YEAR ORDINARY HIGH WATER PEAK PLAT, PLATING POST-CONSTRUCTION RUNOFF PRE-CONSTRUCTION PRELIMINARY PROTECTED Third Edition Stormwater Standards Manual September 2008 Page 9 PUBLIC ROAD QUALIFIED WETLAND RAINWATER AND LAND DEVELOPMENT RATIONAL REGULATORY REGULATORY RELEASE RETENTION RETENTION REVERSE SLOPE RIPARIAN RIPARIAN RIPARIAN RUNOFF RUSLE (REVISED UNIVERSAL SOIL LOSS EQUATION) ..149 SEDIMENT SEDIMENT SHEET SHORT SOIL AND WATER CONSERVATION SOIL SOIL DISTURBING SOIL GROUP, SOIL SPECIAL FLOOD HAZARD AREA (SFHA) ..150 SOURCE STORM Stormwater Stormwater QUALITY Stormwater Stormwater Standards Stormwater STRUCTURAL SUBSTANTIAL SWPPP ( Stormwater POLLUTION PREVENTION PLAN) ..151 Third Edition Stormwater Standards Manual September 2008 Page 10TN.

10 151 TEMPORARY SOIL EROSION AND SEDIMENT CONTROL TEN YEAR FREQUENCY TIME OF TWO YEAR FREQUENCY TREATMENT UNSTABLE WATER WATERBODY WETLAND WET WETTED APPENDIX B: BEST Management PRACTICES ..154 CONSTRUCTION SITE RUNOFF CONTROL ..154 1. VEGETATION Description ..154 Design 2. Description ..154 Design 3. Description ..155 Design Material ..155 Site Preparation ..155 Anchoring ..155 4. STABILIZATION OF DENUDED Description ..158 Design 5. TEMPORARY Description ..158 Design Seedbed ..159 Third Edition Stormwater Standards Manual September 2008 Page 11 Soil Seeding Mulching ..159 6. PERMANENT Description ..160 Design Seedbed Soil Seeding Dates and Soil Conditions ..160 Mulching or Matting ..160 7. Description ..161 Design Site Preparation.