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Draft Environmental Impact Statement

Photo of DEIS Cover

On the Path to a Preferred Alternative


SR 520 Draft EIS at a Glance:

What is an Environmental Impact Statement and what's in it?
An Environmental Impact Statement (EIS) is a document that provides comprehensive information about a project's purpose and need, proposed plans, and potential environmental effects in areas such as wetlands and wildlife, noise and future traffic operations. Creating an EIS is required as part of the National Environmental Policy Act (NEPA) and the State Environmental Policy Act (SEPA). Before an EIS can become final, it must be released in draft form for the public to review, comment on and ask questions about.

Why is the SR 520 Bridge Replacement and HOV Project's draft EIS important to me?
Publishing the draft EIS is a key step along the path to identifying a preferred alternative for the bridge replacement. This is an important opportunity for the public to formally comment on the project's effects and have their comments tracked, published and addressed by the project team in the final version of the EIS.

What is evaluated in the SR 520 Bridge Replacement and HOV Project's draft EIS?
The SR 520 draft EIS looks at 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.

How can I see the draft EIS?
There are a number of ways to receive and/or review the draft EIS:

  • View the draft EIS below.
  • Request a daft EIS CD by emailing SR520Bridge@wsdot.wa.gov
    Please be sure to provide your name, phone number and mailing address in the email.

August 11, 2006 — Draft Environmental Impact Statement

  • Cover and Table of Contents (pdf 427 kb)
  • Chapter 1 - Introduction to the project (pdf 1.1 mb)
  • Chapter 2 - Project Area: Then and Now (pdf 3.5 mb)
  • Chapter 3 - Developing the Alternatives (pdf 5.4 mb)
  • Chapter 4 - Comparison of the Alternatives (pdf 2.3 mb)
  • Chapter 5 - Detailed Comparison of Alternatives: Seattle (pdf 3.8 mb)
  • Chapter 6 - Detailed Comparison of Alternatives: Lake Washington (pdf 556 kb)
  • Chapter 7 - Detailed Comparison of Alternatives: Eastside (pdf 2.9 mb)
  • Chapter 8 - Construction Effects (pdf 1.6 mb)
  • Chapter 9 - Other Considerations and Index (pdf 717 kb)
Appendices and Addenda
A Description of Alternatives and Construction Techniques
Appendix (pdf 1 mb) Addendum (467kb)
B Agency Coordination and Public Involvement (pdf 629 kb)
C Air Quality Discipline Report
Appendix (pdf 1.1 mb) Addendum (pdf 722 kb)
D Cultural Resources Discipline Report
Appendix (in four parts): Part 1 (pdf 5.1 mb) Part 2 (pdf 5.5 mb)
Part 3 (pdf 5.8 mb) Part 4 (pdf 5.3 mb)
Addendum (in four parts) - Part 1 (pdf 5.4 mb) Part 2 (pdf 5.2 mb)
Part 3
(pdf 5.3 mb) Part 4 (pdf 5.2 mb)
E Ecosystems Report
Appendix (in three parts):
Part 1 (pdf 3.8 mb) Part 2 (pdf 5.2 mb) Part 3 (pdf 4.7 mb)
Addendum (in two parts): Part 1 (pdf 6.2 mb) Part 2 (pdf 6.8 mb)
F Energy Discipline Report
Appendix (pdf 322 kb) Addendum (pdf 800kb)
G Environmental Justice Analysis
Appendix (pdf 1.1 mb) Addendum (pdf 1.1 mb)
H Geology and Soils Discipline Report
Appendix (in two parts): Part 1 (pdf 5.2 mb) Part 2 (pdf 5.4 mb)
Addendum (pdf 4.1 mb)
I Hazardous Materials Discipline Report
Appendix (pdf 1.3 mb) Addendum (pdf 2 mb)
J Indirect and Cumulative Effects Discipline Report
Appendix (in three parts):
Part 1 (pdf 6.1 kb) Part 2 (5.4 mb) Part 3 (pdf 4.7 mb)
Addendum (pdf 4.7 mb)
K Land Use, Relocations and Economics Discipline Report
Appendix (pdf 5.6 mb)
Addendum (in two parts): Part 1 (pdf 4.6 mb) Part 2 (pdf 4.2 mb)
L Navigable Waterways Discipline Report
Appendix (pdf 2.7 mb) Addendum (pdf 766 kb)
M Noise Discipline Report (in three parts):
Part 1 (pdf 5.7 mb) Part 2 (pdf 6.1 mb) Part 3 (pdf 5.4 mb)
Addendum (pdf 3.9 mb)
N Public Services and Utilities Discipline Report
Appendix (pdf 783 kb) Addendum (pdf 1.1 mb)
O Recreation Discipline Report
Appendix (in two parts): Part 1 (pdf 5.5 mb) Part 2 (pdf 4.8 mb)
Addendum (in four parts): Part 1 (pdf 5.8 mb) Part 2 (6.1 mb)
Part 3 (4.7 mb) Part 4 (5.9 mb)
P Draft Section 4(f) Evaluation
Appendix (in four parts): Part 1 (pdf 5 mb) Part 2 (pdf 4.7 mb)
Part 3 (pdf 5.4 mb) Part 4 (pdf 2.7 mb)
Addendum (in four parts): Part 1 (pdf 4 mb) Part 2 (pdf 5.6 mb)
Part 3 (pdf 4.7 mb) Part 4 (pdf 6 mb)
Q Social Discipline Report
Appendix (pdf 6.9 mb) Addendum (pdf 1.2 mb)
R Transportation Discipline Report
Appendix (in six parts):
Part 1 (pdf 5.1 mb) Part 2 (pdf 5.4 mb) Part 3 (pdf 5.2 mb)
Part 4 (pdf 5.6 mb) Part 5 (pdf 6.2 mb) Part 6 (4.6 mb)
Addendum (pdf 6.5 mb)
S Visual Quality and Aesthetics Discipline Report
Appendix (in two parts): Part 1 (pdf 5 mb) Part 2 (pdf 4.4 mb)
Addendum (pdf 950 kb)
T Water Resources Discipline Report
Appendix (pdf 6.1 mb) Addendum (pdf 1.7 mb)
U 8-Lane Alternative Report (in two parts):
Part 1 (pdf 4.4 mb) Part 2 (pdf 4.4 mb)
V 6-Lane Alternative Options Report (in two parts):
Part 1 (pdf 5.2 mb) Part 2 (pdf 5.7 mb)
W Madison Park Bicycle/Pedestrian Path Options Technical Memorandum (in four parts):
Part 1 (pdf 6.3 mb) Part 2 (pdf 5.7 mb) Part 3 (pdf 4 mb) Part 4 (pdf 6.2 mb)
X Pacific Street Interchange Option Location Analysis (pdf 1.3 mb)

Can I still comment on the draft EIS?
The official comment period for the draft EIS ended on October 31, 2006. The comment period lasted for 74 days; from August 18, 2006 through October 31, 2006. All comments received during the comment period will be addressed in the final EIS.

Will there be a supplemental draft EIS?
In 2009, project planners will provide the public with a supplemental draft EIS. The supplemental study will contain more detailed information on what the 4+2 replacement SR 520 corridor could look like.

For more information:
Call:
206-770-3500
E-mail: SR520Bridge@wsdot.wa.gov