WSDOT Projects

New Design Options - West-side Mediation Process

West side mediation design options:
• 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)


WSDOT continues to participate in the mediation process. The mediation participants continue to consider ways to improve these design options. Further evaluation of the recommended design options will be included in the supplemental draft environmental impact statement.

 
6-Lane Design Options — Eastside

South Kirkland Park & Ride Transit Access
Provides improved access for transit to the South Kirkland P&R from eastbound SR 520, and from the South Kirkland P&R to westbound SR 520.  Can be built on either 108th Avenue NE or on Bellevue Way.  See associated plans and cost estimates below.

View South Kirkland transit access plan at Bellevue Way (jpg 268 kb)

View South Kirkland transit access plan at 108th Avenue NE (jpg 289kb)


Align SR 520 Bicycle/Pedestrian Path to the North
Keeps SR 520 bike path to the north of the highway as it extends to the east from the SR 520 bridge east highrise; couples with a realigned Points Loop Trails separated by a buffer to distinguish between the local and regional trails, while eliminating sharp turns and crossings over the highway.

View Medina/Points plans with north-side bike path (jpg 312 kb)


Eliminate Evergreen point Freeway Transit Stop
Removes both eastbound and westbound freeway transit stops at Evergreen Point Road.  Reduces footprint of future highway in Medina at Evergreen Point Road area; lessens property impacts.

View Medina/Points plans with north-side bike path, no Evergreen Point transit station (jpg 317 kb)

New 6-Lane Design Options — Seattle

Pacific Street Interchange 
This option would relocate the Montlake/SR 520 interchange north to Pacific Street (see plans below) by adding a bridge between Pacific Street and SR 520 near Marsh Island.

View Pacific Interchange Option (jpg 598 kb) as developed by WSDOT .
View Pacific Interchange Option simulation (jpg 70 kb).


Second Montlake Bridge
Adds second three-lane drawbridge parallel and just east of current Montlake Bridge across Montlake Cut for more traffic capacity to/from Montlake/SR 520 interchange.  Each bridge would provide one-way, three-lane traffic flow in either the north- or southbound direction. 

View proposed Second Montlake Bridge option (jpg 194 kb)


Remove Montlake Transit Freeway Stop
Removes both the eastbound and westbound Montlake freeway transit stops.  Reduces the footprint of the 6-Lane Alternative through Montlake neighborhood by approx. 40 feet. 

View narrowed SR 520 bridge plans without a Montlake transit freeway stop (jpg 219 kb)

Why the new options?

They represent many common goals that WSDOT, its partner agencies and the local communities are hoping to achieve:

• Narrow the 6-Lane Alternative through Portage Bay and Montlake
• Improve transit reliability between Sound Transit’s proposed LINK light rail station at Husky Stadium and buses on SR 520
• Improve HOV access
• Design the project to enhance local communities — architectural treatments, highway lids, vistas, etc. 
• Design a facility that is structurally feasible and cost effective
• Preserve options for future high capacity transit (HCT)

WSDOT is pleased that the options proposed by Montlake start with the
assumption of the 6-Lane Alternative, with the Evergreen Point Floating Bridge
being built first. The neighborhood recognizes the importance of preserving this
facility and keeping it safe for its many thousands of daily travelers. This is WSDOT’s first priority.

Written detail of the design options at specific locations is flushed out below.  Scroll down for more.

Details

Throughout the development of these Westside options, WSDOT has worked
closely with the Montlake and other Westside community leaders and
consistently weighed new options against these common goals. WSDOT has
held regular meetings to report on analysis completed and worked with these
communities and our partner agencies to determine what options should move to
the next stage of analysis.

Using all of the information and feedback received, WSDOT has determined that
the following four design options for the 6-Lane Alternative should move forward
for further analysis:

• No Freeway Transit Stop at Montlake: WSDOT will further explore the
  option of eliminating the Montlake Freeway Transit Stop as a way to reduce
  lane-width through Montlake and Portage Bay. WSDOT is working with Metro
  and Sound Transit to determine how this function could be served without the freeway transit stop.
  
• High-Level Structure Across Portage Bay: WSDOT has determined that a
  high-level bridge through Portage Bay and Montlake is possible. The option
  that WSDOT will explore further is a concrete structure type known as a box
  girder. It would include architectural features in the design to enhance the
  aesthetics of the structure. This option allows the inclusion of noise walls
  along Portage Bay — a key consideration to mitigate highway noise.
  
• Pacific Street Interchange: Another option is to remove the SR
  520/Montlake interchange, and replace it with a new interchange at Pacific
  Street. This would narrow the 6-Lane Alternative across Portage Bay by
  eliminating the on-off ramps at Montlake. The Pacific Interchange would
  involve a new crossing of the Ship Canal from SR 520 to Pacific Street, with
  the connection point occurring adjacent to the Arboretum near Marsh Island.
  The Pacific Street Interchange could be applied to either a high-level structure or the currently planned 6-Lane Alternative at Portage Bay.
  
• Second Montlake Bridge: At the request of several partner agencies,
  WSDOT will further review the addition of a second bridge across the
  Montlake cut that would be similar in design to the current Montlake Bridge.
  This would be evaluated to determine whether it would offer improved transit
  operations through the Montlake corridor.

Design Options Eliminated
There were a number of other ideas evaluated that are not moving forward for
further review. Two of these were the bridge types initially recommended by the
Montlake community. Both the suspension bridge and cable-stayed bridge
structures were eliminated for the following reasons:

• Suspension Bridge: WSDOT determined that a suspension bridge would
  not work for three primary reasons. First, suspension bridges need to travel
  in a fairly straight line, which was not possible within this curved corridor.
  Secondly, a connection could not be made to the new Pacific Street
  Interchange over Marsh Island. Finally, the size of the three to four support
  towers for a suspension bridge, at approximately 630’ in height, would have
  been nearly the height of the Space Needle and out of character with the
  surroundings.
  
• Cable-Stayed Bridge: WSDOT determined that a cable-stayed bridge has
  two primary fatal flaws that make it infeasible in this area. With such a high
  bridge, noise would reach a larger group of neighborhoods in the area than
  the currently planned structure. It is highly likely that noise walls could not be
  installed on this type of structure due to instability that would be created with
  wind. Without noise walls, it would be nearly impossible to mitigate noise
  issues. Similar to the suspension bridge, the size and scale of the support
  towers, at nearly 500’ in height, was also an issue.