1. Managing the Environmental & Project Development Process StormwaterManagement

2. Regulations Federal Water Pollution Control Act (Clean Water Act) Federal Water Pollution Control Act (Clean Water Act) National Environmental Policy Act (NEPA) National Environmental Policy Act (NEPA) ORC Chapter 6111 (Water Pollution Control) ORC Chapter 6111 (Water Pollution Control) Ohio EPA National Pollutant Discharge Elimination System (NPDES) Permits Ohio EPA National Pollutant Discharge Elimination System (NPDES) Permits Construction General Permit (CGP) Construction General Permit (CGP) Watershed Specific CGP Watershed Specific CGP

3. Stormwater Pollution Managing the Environmental & Project Development Process Primary Pollutants Sediment Sediment Heavy Metals Heavy Metals Oil & Grease Oil & Grease Solids Solids Salt SaltSources Brake dust, tire wear, fluids Brake dust, tire wear, fluids Litter Litter Construction Construction Maintenance Activities Maintenance Activities Atmospheric Deposition Atmospheric Deposition

4. Stormwater Regulations Managing the Environmental & Project Development Process Permits Construction General Permit Construction General Permit Watershed Specific Permit(s) Watershed Specific Permit(s) Administered by OEPA Administered by OEPA Earth-disturbing activities > 1 acre Earth-disturbing activities > 1 acre Primary Requirements: Temporary sediment and erosion controls during construction Temporary sediment and erosion controls during construction Post-construction stormwater management controls after construction (permanent) Post-construction stormwater management controls after construction (permanent)

5. ODOT Responsibilities Managing the Environmental & Project Development Process Stormwater Management Plan Required for ODOT’s “MS4” Stormwater Permit Required for ODOT’s “MS4” Stormwater Permit Reduce the discharge of pollutants from ODOT’s storm sewer system Reduce the discharge of pollutants from ODOT’s storm sewer system Minimum Control Measures (MCM’s) Minimum Control Measures (MCM’s) MS4 = Municipal Separate Storm Sewer System

6. NPDES Managing the Environmental & Project Development Process Supplemental Specification 832 Supplemental Specification 832 Temporary sediment and erosion control during construction Temporary sediment and erosion control during construction Stormwater Regulations & ODOT Responses L&D Manual, Vol. 2 Drainage Design Post construction stormwater management controls (after construction - permanent) Post construction stormwater management controls (after construction - permanent)

7. NPDES Managing the Environmental & Project Development Process Post-Construction Stormwater Management Required to Treat: Required to Treat:  Water Quality Remove pollutants Remove pollutants  Water Quantity Amount of stormwater that enters a stream Amount of stormwater that enters a stream Challenge Comply with permit requirements Comply with permit requirements Fit into linear project footprint Fit into linear project footprint Limited ability to acquire right of way Limited ability to acquire right of way

8. NPDES Managing the Environmental & Project Development Process ODOT BMP Toolbox Vegetated Filter StripVegetated Filter Strip Vegetated BiofilterVegetated Biofilter Manufactured SystemsManufactured Systems Extended DetentionExtended Detention Retention BasinRetention Basin Infiltration TechniquesInfiltration Techniques Bioretention CellBioretention Cell Constructed WetlandsConstructed Wetlands Post-Construction Stormwater Management

9. NPDES STORMWATER Managing the Environmental & Project Development Process Vegetated Filter Strip Vegetated portion of the graded shoulder Vegetated portion of the graded shoulder Vegetated foreslope Vegetated foreslope Vegetated Biofilters Vegetated portion of the Vegetated portion of the graded shoulder graded shoulder Vegetated slope Vegetated slope Vegetated ditch Vegetated ditch Post-Construction Stormwater BMPs

10. NPDES STORMWATER Managing the Environmental & Project Development Process Manufactured Systems Proprietary underground structureProprietary underground structure Offline configuration with existing storm sewerOffline configuration with existing storm sewer Removes particulate matter through settlement or other meansRemoves particulate matter through settlement or other means NOTE: There are many different types of manufactured systems from a variety of companiesNOTE: There are many different types of manufactured systems from a variety of companies Post-Construction Stormwater BMPs

11. NPDES STORMWATER Managing the Environmental & Project Development Process Extended Detention “Dry pond”“Dry pond” Captures storm water during rain events and slowly releases the entire captured volume over a period of time leaving a dry bottomCaptures storm water during rain events and slowly releases the entire captured volume over a period of time leaving a dry bottom Retention Basins “Wet pond”“Wet pond” Has a minimum water surface elevation between storms that is defined as the permanent pool.Has a minimum water surface elevation between storms that is defined as the permanent pool. Captures storm water during rain events and slowly releases the captured volume over a period of time.Captures storm water during rain events and slowly releases the captured volume over a period of time. Post-Construction Stormwater BMPs

12. NPDES STORMWATER Managing the Environmental & Project Development Process Post-Construction Stormwater BMPs Infiltration Techniques Storm water filters through substrate consisting of soil, sand, or gravel Discharges treated storm water into ground water rather than into surface waters Bioretention Cells Depressed, low-lying areas that treat storm water through evapotranspiration and filtering Underlying perforated storm sewer or underdrain carries treated storm water to an outlet Extensive vegetation assists in the filtration of the storm water prior to filtering through the soil Constructed Wetlands Treat storm water through bio-retention Designed in a similar manner as a retention basin Depressed, heavily planted areas designed to maintain a dry weather flow depth of 0.5 to 2 feet

13. NPDES STORMWATER Managing the Environmental & Project Development Process Stormwater Associated with Construction Activity in the Big Darby Creek Watershed and Olentangy Watershed Watershed Specific Permits includes: Groundwater Recharge, if applicable Riparian Setback Mitigation Temporary Sediment Basin Locations Ohio EPA review and approval of SWPPP

14. Managing the Environmental & Project Development Process Stormwater Associated with Construction Activity in other specific watersheds: OEPA has developed TMDL Reports for 50 impaired watersheds The following watersheds have water quality report recommendations for developing a watershed specific Construction General Permit:  Chagrin River  Little Miami River

15. Construction Activity Stormwater Permits Managing the Environmental & Project Development Process Consequences for ODOT: Increased project footprint Increased project footprint Additional assessment and documentation: Additional assessment and documentation:  Wider ditches, stormwater ponds & wetlands  Structural additions, manufactured systems… Increased mitigation: Increased mitigation:  Stream restoration  Environmental covenants On going Research On going Research

16. Questions? Managing the Environmental & Project Development Process Becky Humphreys (614)387-1125 Stormwater Program ManagerBecky.Humphreys@dot.state.oh.us