Updated: August 27, 2020

What’s happening now? East side of I-5: 1st Ave NE between NE 92nd St and NE 95th St, and between NE 92nd St and NE 100th St Beginning as soon as August 24 and continuing over two months, crews will be working on 1st Ave NE between NE 92nd St and NE 95th St, and between NE 92nd St and NE 100th St as a part of a bicycle lane installation. During this work, the southbound travel lane will be closed, and the northbound travel lane will be open (see detour map below). Work during this time includes: Sidewalk, curb ramp, and gutter restoration

Paving and striping

Between the hours of 9 AM and 3 PM, traffic will be reduced to one lane and directional travel will be maintained with flaggers. Impacts include temporary wait periods, pedestrian detours, and changes to the King County Metro bus stop at NE 92nd St. East side of I-5: 1st Ave NE between NE 100th St and NE 103rd St Intermittent lane closures along 1st Ave NE between 7 AM and 3:30 PM, with northbound and southbound traffic maintained

Temporary bridge deck handrail work

Walkway construction and installation

Ongoing concrete work for several pier columns: Placing forms and rebar cages Placing concrete Allow concrete to cure Removing the forms once concrete has cured

Concrete work for retaining wall and bridge footings: West side of I-5: north side of North Seattle College and along N 100th St Construction of structural earth wall

Concrete work for two remaining pier columns

Placing forms and rebar cages Placing concrete Allow concrete to cure Removing the forms once conrete has cured

Installation of bridge girder temporary support blocks

Setting of bridge girders Our commitment to be a good neighbor We will keep you informed and minimize our impacts. During construction, we're committed to working closely with project neighbors and will:

Be available for questions

Provide advance notice about construction through email updates and other promotions

Work closely with North Seattle College to communicate major milestones to students, faculty, and staff

Ensure project signage is clear and effective to encourage safety and caution near active work zones

Maintain access to businesses What to expect during construction Dust, noise, and construction vehicle activity, including cranes

Some nighttime and weekend work

Detours for people walking and biking

Traffic lane restrictions and closures

Construction staging and parking impacts near the construction sites, including on the North Seattle College campus on the west side and NE 100th St (at 1st Ave NE) on the east side

Closure of the North Seattle Park & Ride on 1st Ave NE Long-term closure of North Seattle Park & Ride The North Seattle Park and Ride (10001 1st Ave NE) will now be closed until fall 2021 for construction of the Northgate Ped/Bike Bridge project. The Seattle Department of Transportation is partnering with the Washington State Department of Transportation and King County Metro during the construction of the bridge. The lot will be used to stage equipment and materials for the duration of the closure. For more details, including alternative parking areas, view the full notice here. Questions? Contact the project team at NorthgateBridge@seattle.gov If you need this information translated, please call 206-905-3620 Si necesita traducir esta información al español, llame al 206-905-3620 如果您需要此信息翻譯成中文 請致電 206-905-3620

Project overview

The Northgate neighborhood is a major residential and employment destination that continues to grow. With the completion of Sound Transit’s Link light rail station in 2021, the neighborhood is poised to become one of the region’s most active transit hubs. Today, a 10-lane interstate divides the neighborhood, and to walk between North Seattle College and the existing transit center is 25 minutes or more.

Connecting communities on the east and west sides of I-5 in Northgate

We designed a new, accessible, all ages and abilities pedestrian and bike bridge over Interstate 5 (I-5) in Northgate. The Northgate Ped/Bike Bridge will improve access to communities, services, and opportunities on the east and west sides of I-5 in Northgate and Licton Springs, helping knit together a historically divided area. It’ll also reduce travel time for people walking and biking between the east and west sides of I-5. When complete, the bridge will help connect the neighborhood’s thriving job and retail centers with the rest of the city and region.

The new bridge will span roughly 1,900 feet over I-5, landing at North Seattle College on the west side and at 1st Ave NE and NE 100th St, near the future light rail station, on the east side.

The project consists of four main parts:

Bridge spans over I-5

Western approach between North Seattle College and wetland area, connecting to College Way N and N 100th St

Eastern approach between I-5 and 1st Ave NE at NE 100th St, near the King County Transit Center

Multi-use path along 1st Ave NE

The project will benefit the area by providing:

A new connection over I-5, decreasing travel times for people walking and biking between the 2 sides of the highway

Safety improvements and access for people walking and biking throughout the Northgate area

Better access to regional transit at the King County Transit Center and future Link light rail station, resulting in increased use of transit facilities

Improved connections between the Northgate retail center for its employees and customers and for residents and visitors to other nearby amenities, such as parks and medical and social services

Project location







Design renderings

The view from I-5 traveling north.



The user experience walking or biking across the bridge.



A view of the bridge, looking east.



1st Ave NE street improvements

1st Ave NE features

Upon project completion, 1st Ave NE will be restored and include a new2-way protected bike lane (PBL), between 92nd and 103rd alongthe west side of the street (see image below).

At NE 103rd St, people biking will use the crosswalk to accessthe east side of the street, where a multi-use path or widenedsidewalk will continue north to Northgate Way.

1st Ave NE will have one vehicle travel lane in each directionwith a left‑turn pocket at 100th St. The existing transit center busstops will be relocated to the east side of 1st Ave NE, betweenNE 100th and NE 103rd streets. King County Metro plans to restore transit stops on 1st in 2021.



North Seattle's growing bike network

Once complete, the PBL will connect with the new NorthgateBridge at NE 100th St, the existing bike lanes on 92nd, and othercommunity connections in the area. Theseimprovements will provide easy access to regional transit and tothe citywide network of walking and biking routes.

Protected bike lanes combine the elements of a multi-use pathwith a conventional bike lane. They provide space for bikes thatis separated from vehicles, parking lanes, and sidewalks.





Recent cost-saving changes

We formed a new design team in 2016 to help reduce project costs and meet project goals. The team developed a bridge design that includes the following cost-saving changes and design improvements:

Original design (prior to 2017) Revised design (2017 to present) 20-foot-wide walkway on bridge 16-foot-wide walkway on bridge 2,100-foot-long bridge length Shortened bridge length to 1,900 feet East approach conflicted with WSDOT Park-and-Ride at 1st Ave NE East approach modified as it touches down near 1st Ave NE, simplifying the connection and preserving the WSDOT Park-and-Ride lot West approach included stairs at the North Seattle College, with limited sight distance West approach modified to improve sight distances and make a more direct connection Complicated construction approach Standard construction approach to reduce project duration Tube/truss design (enclosed) More open structure and more graceful bridge transition

Finally, an added benefit of the revised design is enhanced user experience with features such as a wetland wildlife overlook and a view of arriving light rail trains at NE 100th St.

What we’ve heard through design

Based on community input throughout the project, we know there’s interest in:

Minimizing environmental impacts of the bridge by making sure, for example, that the project doesn’t disturb wildlife during construction and ensuring the bridge’s drainage system (for stormwater) is designed to enhance wetlands on the west end

Ensuring safety and security of all bridge travelers

Wayfinding and traffic control

The experience of people biking and using other wheeled devices (e.g., scooters, wheelchairs, strollers, rollerblades, suitcases, etc.)

Connecting the bridge to other infrastructure, including neighborhood bike routes

Separating or managing modes of traffic on the bridge

Other topics of interest included the project’s cost, the bridge’s durability, and maintaining vegetation.

We value the community input provided to date and thank you all for your continued interest.

Tree mitigation plan

Throughout our preconstruction outreach, the project team heard from many people asking about our tree mitigation plan. We will be removing 93 trees during this project, and we will be planting 464. The map below shows the full details. You can click on the map to download a PDF of the plan.





Designing for a safer bridge

During each phase (planning, design, and pre-construction) of public outreach, we heard that bridge safety is a priority for all bridge users. The sections below outline how safety is incorporated into all aspects of the bridge's design.

Design and accessibility

Throughout the design process, we used an approach called Crime Prevention Through Environmental Design (CPTED). This approach is based on the idea that people's behavior within an urban environment is influenced by the design of that environment.



CPTED strategies include things like providing ample lighting to avoid blind spots, maximizing sight distance and visibility (sometimes called "passive surveillance"), and using materials that promote easy maintenance. This strategy also aims to create spaces that give a sense of ownership of public space and a sense of shared responsibility for personal security.



There are several safety elements on the bridge, including:

Minimal surface area for vandalism

Overhead pedestrian lighting

Emergency call boxes

Pedestrian guardrails

Lighting on handrails

Throw fences

The City of Seattle strives to make city programs, services, and activities equally accessible to all. Our bridge design complies with 2010 ADA Standards and includes the following features:

A bridge slope of 4.3%, except between the Sound Transit mezzanine and the NE 100th St level, which is 8.1%. This section has ADA-compliant handrail grips and 1.8%-slope landings every 30 feet to provide resting places.

Elevator access via the Northgate Station Garage, including where the bridge connects to the Northgate Link light rail station, during normal hours of operation.

Curb ramps along 1st Ave NE and NE 100th St, where the bridge spur lands.

Accessible pedestrian signals at the intersection of 1st Ave NE and NE 100th St, which will offer push-button activation, audible signals, and vibrations to indicate when it's safe to cross the street.





Materials

All bridge materials and connections will go through intensive testing during construction, including the spans across I-5, which will undergo rigorous quality assurance testing during fabrication, assembly, and installation. The trusses of our bridge will be made of steel, a common and proven material and design for hundreds of bridges across the nation.



Life expectancy

Our bridge was required to meet the 75-year design life expectancy criteria consistent with the American Association of State Highway and Transportation Officials (AASHTO) design codes. Not only does our design meet this standard, it's expected to exceed a lifespan of more than 100 years with routine maintenance during its service life.



Environmental

We selected vegetation and greenery around the bridge with safety in mind. Creating park-like qualities on the trails and spaces near the bridge will provide a comfortable and enjoyable atmosphere and a "sense of place" for all users. Examples of this can be seen on the west side with a wildlife overlook, and on the east side where we're proposing a "gallery forest," or screen of tall and narrow trees between the bridge and the freeway, providing relief from views of the freeway and filtering air quality.

Additional environmental features include:

Planting low-growing shrubs and bushes around the bridge

Trimming, thinning, or removing existing trees and undergrowth to create open sight lines

Carefully designed plantings on the west side of the bridge so that pedestrians on the landing will have a clearer view of North Seattle College (NSC), and those on the NSC playing field and in the parking lot will see bridge users approaching

Schedule

We expect construction to begin early 2020, and to be complete in fall 2021, prior to the opening of the Link light rail station in September 2021.

Funding

We’ve secured funding from various sources in addition to the voter-approved Move Seattle levy. These include SDOT, Sound Transit, Washington State, and additional local funds.

Stay informed

Email is the best way to stay up to date on the project during the entire construction process.

Click here to sign up to receive project email updates

Park and Ride Information

Click this link for more details about which Park and Rides are open and available throughout construction.





Outreach events

Date Events January 9, 2020 Construction drop-in session at Olympic View Elementary January 8, 2020 Construction drop-in session at Aljoya Thornton Place January 7, 2020 Construction drop-in session at North Seattle College September 28, 2019 Live in D5 September 25, 2019 North Seattle College Fall Fest September 3, 2019 Olympic View Ice Cream Social July 17, 2019 Maple Leaf Summer Social July 13, 2019 Live in D5 April 24, 2019 North Seattle College Fair October 24, 2018 Maple Leaf Community Council July 19, 2018 Thornton Creek Alliance July 18, 2018 Maple Leaf Summer Social June 30, 2018 Live in D5! May 11, 2018 North Seattle College Board of Trustees meeting April 18, 2018 North Seattle College Earth Fair April 18, 2018 North Seattle College Earth Fair March 21, 2018 Drop-in session at Neighborcare Health at Meridian March 20, 2018 Drop-in session at Aljoya Thornton Place March 19, 2018 Drop-in session at North Seattle College February 8, 2018 Sierra Club November 28, 2017 North Seattle College campus meeting November 2, 2017 Haller Lake Community Club August 13, 2017 Idriss Mosque BBQ August 9, 2017 Seattle Pedestrian Advisory Board Walking Tour August 3, 2017 Public open house July 26, 2017 Maple Leaf Summer Social July 22, 2017 Live in D5! June 30, 2017 Department of Neighborhoods Community Conversation Meridian Manor June 14, 2017 Maple Leaf Community Council June 14, 2017 Seattle Pedestrian Advisory Board June 7, 2017 Seattle Bicycle Advisory Board May 18, 2017 Seattle Design Commission May 6 King County Metro

Transit Oriented Development public meeting April 29, 2017 Housing Affordability and Livability community open house (sponsored by Dept. of Neighborhoods) June 22, 2016 North District Council May 25, 2016 Feet First May 18, 2016 Licton Springs Community Council May 17, 2016 Victory Heights Community Council May 16, 2016 North Seattle College (Campus meeting) May 5, 2016 North Seattle College (students) October 15, 2015 Public open house September 17, 2015 Seattle Design Commission briefing August 18, 2015 Seattle Design Commission subcommittee meeting July 29, 2015 Maple Leaf Summer Social July 15, 2015 North Seattle Chamber of Commerce June 17, 2015 Licton Springs Community Council June 17, 2015 Seattle Pedestrian Advisory Board June 24, 2015 Pinehurst Community Council May 27, 2015 Northwest District Council Briefing May 26, 2015 Cascade Bicycle Club: Connect Northgate May 22, 2015 Seattle Neighborhood Expo May 12, 2015 Meadowbrook Community Council May 2015 Seattle Pedestrian Advisory Board April 29, 2015 Maple Leaf Community Council April 22, 2015 North Seattle College Earth Day Symposium October 21, 2014 North Seattle College September 10, 2014 Public briefing June 3, 2014 Open house March 2014 Sound Transit open house February 2014 Seattle Bicycle Advisory Board February 2014 Seattle Pedestrian Advisory Board

Materials

January 2020



December 2019

Environmental Review

August 2018

April 2018

March 2018

February 2018 - Project information folio

December 2017 - Email update

November 2017



October 2017 - Email update



August 2017

July 2017 – Email update

June 2017

April 2017 – Project fact sheet

Previous Design Materials:

October 2015

September 2015 – Seattle Design Commission presentation

June 2015 – 2015 TIGER Grant application

July 2015 – Project factsheet

November 2014 - Northgate Pedestrian and Bicycle Bridge: Alternative Development and Selection report



October 2014 – Presentation

September 2014 – Presentation

August 2014 – Presentation

June 2014

April 2014 - TIGER Grant application (Not selected. TIGER Grant is a highly competitive federal funding source)

April 2014 - Project fact sheet

February 2014 - Presentation

Background Resources