Georgia DOT Environmental Considerations

Eugene Hopkins, P.E. GDOT, Office of Road Design

Georgia DOT’s function

Design, build, and maintain State routes, US routes and Interstate HighwaysProvide financial assistance to Local governments on other transportation facilitiesOther modes of transportation GDOT is involved with include: airports, ports, bike paths, railroads, public transportation, park and ride lots, etc.

Georgia DOT’s Function (cont’d)

GDOT generally uses a mix of federal and state tax revenuesFederal oversight is required for any project that uses federal fundsFederal Highway Administration reviews project environmental documents for compliance

Concept Development

“Concept decisions shall be sensitive to environmental resources. Wherever possible, environmental resources are to be avoided, but where avoidance is not prudent, the impacts are to be minimized and mitigated.”

-- GDOT Plan Development Process, pg 32

Environmental ConsiderationsMost projects are linear corridors that have the

potential to impact environmental resources including:

EcologyHistorySocio Economic, (Environmental Justice)ArcheologyDirect property damages including displacements and impacts to access. Environmental laws and rules such as: National Environmental Policy Act (NEPA) and Georgia Environmental Policy Act (GEPA)

All projects require an environmental evaluation

Ecological resources

Jurisdictional Waters of the USStream buffers of state watersThreatened & Endangered speciesMigratory birdsEssential fish habitatInvasive speciesFloodplains

Balance of Impacts

Balance of Impacts

Section 106 of the National Historic Preservation ActSection 4(f) of USDOT ActArchaeological Resource Protection ActNative American Grave Protection & Repatriation ActTitle VI of the Civil Rights Act Executive Order 12898 – Environmental JusticeNoise Abatement – 23 CFR 772The Clean Air ActSurface Transportation & Uniform Relocation Assistance Act

Section 6(f) of the Land & Water Conservation FundThe Clean Water ActExecutive Order 11990 – Protection of WetlandsExecutive Order 11988 – Floodplain ManagementRivers & Harbors Act of 1899Coastal Zone Management Act of 1972Endangered Species Act of 1973Fish & Wildlife Coordination ActFarmland Protection Policy Act of 1981ETC. . . .

Natural Resource laws

Section 404 of the Clean Water ActFish & Wildlife Coordination ActErosion & Sedimentation ActSection 7 of the Endangered Species ActMigratory Bird Treaty Act

Natural Resource laws (cont’d)

Magnuson-Stevens Fishery Conservation & Management ActExecutive Order 13112 – Invasive SpeciesSections 9 and 10 of the Rivers & Harbors ActExecutive Order 11988 – Floodplains

Jurisdictional Waters of the US

Wetlands, streams (& their buffers), open watersDelineate boundaries – place on project layouts & plansOccurs during concept stage

Gum swamp wetlands

Bottomland hardwood wetlands

Streams – Chattooga River

Intermittent streams

Open waters

Stream buffers

Essential Fish Habitat

Identify EFH – waters & bottom habitats necessary to a marine species’ lifecycle Coastal counties – Camden, Glynn, McIntosh, Liberty, Bryan, & Chatham

Essential Fish Habitat

GDOT Stormwater Detention Policy

The roadway construction produces a 10% increase in peak flow volume for the design year storm event at any outfall,In areas where existing storm drain systems downstream of the project have been determined not to have sufficient capacity to carry the required design storm event,At outfall locations where significant portions of the receiving channel is in a degraded or unstable condition,The project impacts an existing detention facility,At outfall locations where the receiving channel is located in or leads to an environmentally sensitive area (wetlands, habitats, etc.), orAs an alternative to mitigation of environmental impacts.

GDOT Stormwater Detention Policy (cont’d)

Detention facilities, when utilized, will be designed so as not to increase the post-development peak flow over the pre-development peak flow. The facility will be designed and analyzed using the 2, 5, 10, 25, 50, and 100-year storm events.The use of detention facilities shall not be required on projects where the disturbed area is less than five acres.In all cases the engineer should use sound engineering judgment to determine the most appropriate solution involving detentionInfiltration has been used on a limited basis primarily on projects that may impact Threatened and Endangered species

GDOT Erosion Sedimentation and Pollution Control Plan (ESPCP)

GDOT Erosion Sedimentation and Pollution Control Plan (ESPCP)

Prepare detailed ESPCP plan for each stage of construction in accordance with EPD general permit number GAR100002All ESPCP plans prepared for GDOT projects must be certified by a GSWCC level II engineerAll temporary and permanent BMPs meet or exceed the requirements of the Georgia Soil and Water Conservation Commission

GDOT Environmental Policy Overview

All projects adhere to a stringent environmental processImpacts are Avoided, Minimized and Mitigated ESPCP plans are prepared to meet or exceed permit requirementsStormwater detention policy with considerations for infiltration is applicable on all projectsConcrete ditch paving use is minimizedUnnecessary concrete ditch paving is removed and replace with pervious materialsGrass slopes and swales are used to the extent possibleStream buffers are identified, impacts are minimized and impacted buffers are restored

Future considerations

Future laws and rules should clearly differentiate between linear and non-linear projectsOn linear projects, mitigation efforts, such as infiltration basins, typically cause significant additional impacts on riparian buffers that would have otherwise not been impactedLinear projects tend to have numerous, minor impacts whereas non linear project have significant impacts on a small number of watersheds