Highway and Road Projects: When to Treat Runoff William Fletcher Water Resources Program Coordinator Geo/Environmental Section ODOT

Drivers Clean Water Act 401 Water Quality Certification for projects requiring 404 permits 401 Water Quality Certification for projects requiring 404 permits NPDES MS4 permits NPDES MS4 permits TMDLs and 303(d) listings for water quality limited streams TMDLs and 303(d) listings for water quality limited streams

Drivers Endangered Species Act Stormwater management expectations are incorporated into SLOPES IV

Triggers Adding New Impervious Surface Area New roads New roads New or modified alignments New or modified alignments Wider roads, including wider shoulders Wider roads, including wider shoulders

A touch of Pragmatism No one really cares about very small increases in non-traffic bearing new impervious surface area, as long as it doesn’t change the treatment or routing of stormwater from other impervious surfaces Bases for signs Bases for signs Police car pads Police car pads Guardrail flares Guardrail flares

What about bike paths and sidewalks? Not if they are separated from the road, where the intervening ground is unpaved and vegetated, However Bike paths that are really widened roads, and sidewalks that include adding curbs do trigger the need for treatment

Triggers Modifying the drainage system Changing the type of conveyance (ditch to pipe etc.) Changing the type of conveyance (ditch to pipe etc.) Changing the location of the conveyance Changing the location of the conveyance Enlarging the conveyance Enlarging the conveyance Substantially increasing the amount of water carried by the conveyance (Changing the CIA) Substantially increasing the amount of water carried by the conveyance (Changing the CIA)

More Pragmatism Minor changes, such as relocating an inlet, do not trigger the treatment requirement Minor changes, such as relocating an inlet, do not trigger the treatment requirement Repairs to the drainage system do not trigger the treatment requirement Repairs to the drainage system do not trigger the treatment requirementHowever A major replacement of a system could require treatment. A major replacement of a system could require treatment.

Triggers Adding, Replacing or Widening Stream Crossing Structures

Not included are: Seismic Retrofits Seismic Retrofits Repaving Repaving Structural Repairs Structural Repairs Culvert End Replacements or Extentions Culvert End Replacements or Extentions

Triggers Projects that require a CWA 404 permit and “involve” impervious surfaces. Projects that require a CWA 404 permit and “involve” impervious surfaces. “Involve” includes all of the above plus projects that reconstruct a road by removing pavement down to base grade and repaving the surface. “Involve” includes all of the above plus projects that reconstruct a road by removing pavement down to base grade and repaving the surface.

This does not include fixing sink holes in the road, utility repair, or replacing short segments of highway to repair damage. This does not include fixing sink holes in the road, utility repair, or replacing short segments of highway to repair damage.

Water Resources Goals Treat All the stormwater from the Contributing Impervious Area Generated by the Water Quality Design Storm Using Preferred Best Management Practices

Do you need to build something? Not Necessarily Right soils and enough room to infiltrate the stormwater Right soils and enough room to infiltrate the stormwater Sheet flow from the edge of pavement through vegetation Sheet flow from the edge of pavement through vegetation Divert stormwater through vegetation Divert stormwater through vegetation

Preferred BMPS Infiltration techniques Infiltration techniques Bioretention facilities Bioretention facilities Bioslope (“Ecology Embankment”) Bioslope (“Ecology Embankment”) Amended Soil Swales and Filter Strips Amended Soil Swales and Filter Strips Treatment wetlands Treatment wetlands

Resources ODOT Stormwater Management Program Web Page ODOT Stormwater Management Program Web Page ODOT Geo/Environmental Section Technical Bulletin 09-02(b) ODOT Geo/Environmental Section Technical Bulletin 09-02(b) ODOT Water Quality Guidance Document, with Appendices ODOT Water Quality Guidance Document, with Appendices ODOT Hydraulics Manual ODOT Hydraulics Manual DEQ 401 Program Web Page DEQ 401 Program Web Page SLOPES IV (on ODOT G/E Web Page) SLOPES IV (on ODOT G/E Web Page)