Why does WSDOT prepare environmental documentation?

We prepare project environmental documents to meet the requirements of federal and state environmental regulations, NEPA and SEPA. These laws are designed to ensure that environmental considerations are weighed appropriately along with other factors in decision making. 

Completing environmental documentation allows us to move the SR 520 program toward construction.
 

What documentation has WSDOT already completed?

In 2006, WSDOT released the SR 520 Bridge Replacement and HOV Project Draft Environmental Impact Statement. This draft environmental impact statement evaluated plans and potential effects for a "No Build" Alternative, a 4-Lane Alternative and a 6-Lane Alternative, along with design options for the 6-Lane Alternative. An eight-lane alternative was also considered, but was eliminated from further evaluation before the draft EIS was published. 
 

What are NEPA and SEPA?

NEPA is the National Environmental Policy Act, and it went into effect in 1970. It established a process to ensure that information on the environmental effects of a federally funded project is available to the public and decision-makers before a project is implemented. For large projects, NEPA requires the preparation of an environmental impact statement that evaluates environmental effects and identifies any reasonable alternatives that could eliminate or reduce these effects. Smaller projects, or those with fewer impacts, may be required to develop an Environmental Assesment, or qualify for a categorical exclusion.

Washington’s State Environmental Policy Act legislation went into effect in 1971 and established an environmental review process consistent with NEPA for all state projects that are likely to have significant effects on the environment.