WSDOT - SR 520 Bridge and HOV Project - Library

Technical Documents

This page contains studies, reports SR 520-related legislation and findings. The documents are listed in chronological order and categorized by topic.

Conceptual plans and costs-by-segment

A3 - Seattle City Council resolution application to the 6-Lane Alternative with no Montlake transit stop (pdf 797 kb)
K - Six-lane corridor with tunnel through the Arboretum and tunnel under the Montlake Cut (pdf 831 kb)
L - Six-lane corridor with shallow tunnel through the Arboretum (Foster Island Berm) and bridge over the Montlake Cut (pdf 640 kb)

House Bill 2878 - 2008 Supplemental Transportation Budget

House Bill 2878 as passed by legislature and signed by Gov. Gregoire (external site) - March 2008 (pdf 320 kb)

House Bill 1773 - Establishing State Tolling Authority and Statewide Guidelines for Tolls

House Bill 1773 as passed by legislature and signed by Gov. Gregoire (external site) - March 2008 (pdf 80 kb)

House Bill 3096 - Financing the SR 520 Bridge Replacement and HOV Project

House Bill 3096 as passed by legislature and signed by Gov. Gregoire (external site) - March 2008 (pdf 20 kb)

Early Pontoon Construction Project Draft Purpose and Need Statement

Draft Purpose and Need Statement - January 2008 (pdf 243 kb)

SR 520 Finance Plan

SR 520 Finance Plan - January 2008 (pdf 621 kb)
SR 520 Toll Traffic and Revenue Technical Report (pdf 1.5 mb)

SR 520 Draft High Capacity Transit Plan

Draft High Capacity Transit Plan - October 2007 (pdf 3.7 mb)

Toll Feasibility Study

SR 520 and I-90 Toll Feasibility Analysis: Traffic and Revenue Forecasts Technical Memorandum May 2007 (pdf 1.8 mb)

ESSB 6099 as passed by the 2007 Legislature

Engrossed Substitute Senate Bill 6099 (External site) - April 2007 (pdf 24 kb)

Washington Office of State Treasurer’s Report on SR 520 Bridge Replacement and HOV Project Funding Alternatives

Treasurer's Letter – March 30, 2007 (pdf 32 kb)
Final Report – March 28, 2007 (pdf 904 kb)
Governor's Letter – April 3, 2007 (pdf 38 kb)

Governor Chris Gregoire's Findings on the Project

A Path Forward to Action: Findings and Conclusions for the Alaskan Way Viaduct and Seawall replacement and State Route 520 Bridge Replacement Projects December 15, 2006 (pdf 335 kb)
Governor’s press conference December 15, 2006 (video)

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)