Ohio's Standards for Stormwater Management, Land Development and Urban Stream Protection

The Rainwater and Land Development manual defines Ohio's standards and specifications for stormwater management practices implemented during land development. The purpose of this manual is to provide professionals involved in the planning, design, and implementation of land development projects with guidance on how to select, design, and locate stormwater management practices that minimize the adverse impacts of stormwater runoff during and after construction.

Practices detailed in this manual are designed to ensure compliance with Ohio's water quality laws, rules, regulations and policy. Apply these practices based on applicable regulatory requirements, project needs, and site-specific conditions or circumstances. Alternate methods may be available to satisfy a regulatory program requirement but may require the regulated entity to demonstrate the alternate method meets pertinent regulatory requirements.

Originally published by the Ohio Department of Natural Resources in 1996, the Rainwater and Land Development manual is provided by the Ohio Environmental Protection Agency in a series of chapters, subchapters, and appendices. The most current versions are made available for separate downloads through the links below.

The Rainwater and Land Development manual is periodically updated to include additional practices as well as new information on already included practices as research and development occur. Previous versions are archived below for reference.

PLEASE NOTE: A comprehensive revision of the Rainwater and Land Development manual (2006 version with updates through 2014) is currently in progress. New or updated chapters and subchapters will be individually posted throughout the revision process.

Rainwater and Land Development Chapters

Cover and Introductory Information

Introductory Information, including the cover and table of contents (updated 11/06/2014)

Chapter 1 - Planning Stormwater Management for Development Projects

Chapter 1 - Selecting Storm Water Management Practices for Development Projects (2006)

STORMWATER MANAGEMENT PLANNING

• 1.1 — Stormwater Management Objectives (5/2022)
• 1.2 — Development Strategies (11/2022)
• 1.3 — Stormwater Pollution Prevention Plan (under development)

STORMWATER RESOURCE MANAGEMENT PRACTICES 

• 1.4 — Soil Restoration (10/2021)
• 1.5 — Stream Setback (11/2022)
• 1.6 — Wetland Setback (11/2022) 

Chapter 2 - Post-Construction Stormwater Management Structural Practices

Chapter 2 - Post-Construction Stormwater Management Practices 

RUNOFF REDUCTION PRACTICES 

• 2.1 — Impervious Surface Disconnection (10/2021)
• 2.2 — Sheet Flow to Grass Filter or Conservation Area (10/2021)
• 2.3 — Grass Swale (10/2021)
• 2.4 — Green Roof (10/2021)
• 2.5 —  Rainwater Harvesting (10/2021)
  • Rainwater Harvesting Spreadsheet (under development) 

POST-CONSTRUCTION STRUCTURAL PRACTICES 

• 2.6 — Wet Extended Detention Basin (05/2022)
• 2.7 — Dry Extended Detention Basin (2006)
• 2.8 — Extended Detention Constructed Wetland (05/2022)
• 2.9 — Bioretention (03/2023)
• 2.10 — Pervious Pavement (2006)
• 2.11 — Infiltration Basin (2018 Provisional)
• 2.12 — Infiltration Trench (2006)
• 2.13 — Sand Filter (2006)
• 2.14 — Underground Storage Facility (11/2022)
• 2.15 — Other Technologies (under development)

COMMON DESIGN STANDARDS 

• 2.16 — Water Quality Volume (10/2021)
• 2.17 — Soil Infiltration Rate (2018 Provisional)
  • Kfs Correction Spreadsheet (2019)
• 2.18 — Water Quality Flow (10/2021)

APPENDICES 

• 2.A.1 — Design Examples (under development)
• 2.A.2 — Non-traditional Development Guidance (under development)
• 2.A.3 — Critical Storm Method (2022)
• 2.A.4 — Practice Testing Criteria (under development)
• 2.A.5 — Adjusting Hydrologic Soil Group for Construction

Chapter 3 — Non-Sediment Pollution Prevention on Construction Sites

See Chapter 8.

Chapter 4 - Permanent Runoff Control Practices

Chapter 4 - Permanent Runoff Control (2006)

• Grassed Swale
• Level Spreader
• Rock Lined Channel
• Outlet Protection
• Diversion
• Terrace
• Subsurface Drainage

Chapter 5 - Temporary Runoff Control Practices

Chapter 5 - Temporary Runoff Control (updated 3/03/2014)

• Rock Check Dam
• Slope Drain
• Temporary Diversion
• Stream Utility Crossing
• Temporary Stream Crossing
• Water Bar
• De-Watering Measures

Chapter 6 — Sediment Control Practices

Chapter 6 — Sediment Control (2006)

• Sediment Basin
• Sediment Trap
• Silt Fence
• Storm Drain Inlet Protection
• Filter Berm
• Filter Socks

Chapter 7 - Soil Stabilization Practices

Chapter 7 - Soil Stabilization (2006)

• Phased Disturbance
• Clearing and Grubbing
• Tree and Natural Area Preservation
• Construction Entrance
• Dust Control
• Grade Treatment
• Top Soiling
• Temporary Seeding
• Mulching
• Permanent Seeding
• Sodding
• Temporary Rolled Erosion Control Products (Erosion Control Matting)
• Turf Reinforcement Matting

Chapter 8 - Small Construction Site Controls

Chapter 8 - Additional Construction Site Pollution Controls and Small Lot Building Sites (2006)

• Additional Construction Site Pollution Controls
• Small Lot Building Sites

Appendices

Appendix 1 — Post Construction Storm Water Design Examples (under revision)

Appendix 2 — NPDES Permits for Storm Water Discharges from Construction Sites

Appendix 3 - Development Permitting and Approval Process in Ohio

Appendix 4 - Overview of Stream/Wetland Regulations (updated 5/08/2012)

Appendix 5 - Resource Agencies (updated 11/06/2014)

Appendix 6 - Soils with Greatest Potential Use for Infiltration

Appendix 7 - Planning for Streams

Appendix 8 - Glossary

Appendix 10 - Alternative Pre-Treatment for Dry Extended Detention Ponds (updated 5/08/2012)

Archives

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Critical Storm Method

Stream Channel and Flood Plain Erosion

To control pollution of public waters by soil sediment from accelerated stream channel erosion and to control flood plain erosion caused by accelerated stormwater runoff from development areas, the increased peak rates and volumes of runoff shall be controlled such that:

1. The peak rate of runoff from the critical storm and all more frequent storms occurring on the development area does not exceed the peak rate of runoff from a one year frequency storm (of 24 hours duration) occurring on the same area under pre-development conditions.
2. Storms of less frequent occurrence than the critical storm, up to the one hundred year storm, have peak runoff rates no greater than the peak runoff rates from equivalent size storms under pre-development conditions.

The critical storm for a specific development area is determined as follows:

1. Determine by appropriate hydrologic methods the total volume of runoff from a one-year frequency, 24-hour storm occurring on the development area before and after development.
2. From the volumes determined in (a), determine the percentage increase in volume of runoff due to development, and using this percentage, select the 24-hour critical storm from this table.

If the percentage of increase in volume of runoff is:

Download the Ohio Storm Water Control Guidebook

Practice Data Sheets

• Bioretention Data Sheet
• Sediment Basin Data
• Sediment Trap Data  

Technical Memos

These technical memorandums provide updated or new design guidance until a full revision of the Rainwater and Land Development Manual can be issued.

• Gravel, Artificial Turf and Non-Typical Landcover
• Sediment Storage Design for Post-Construction Practices
• Bioretention Filter Bed Area and Ponding Depth Revision
• Runoff Reduction Credit as Groundwater Recharge Mitigation (Big Darby Watershed)
• WQv Drawdown Compliance in Underground Detention Facilities

Contacts