IATC Advocates for Wildlife, Recreation, and Safety Considerations for SR-18

Project Background

SR-18 is a mostly two-lane mountain highway that runs from I-90 all the way to I-5 through the Issaquah Alps and Maple Valley. It has been known for years as the “deadliest highway in Washington” due to the high number of accidents that take place on the road especially over Tiger Mountain where there is no median between opposing lanes of traffic. In 2017 design work began to make improvements on this highway including safety considerations and traffic alleviation with work set to begin in 2021. 

Key changes WSDOT are considering to address these concerns include widening the road to four lanes along a 1.5 miles stretch of the highway between I-90 and Issaquah Hobart Road. Additionally, they are redesigning the interchange between SR-18 and I-90 and considering safety measures at Tiger Mountain Summit which could include medians or a “diamond interchange” to ensure the safety of eastbound turns.

Image of SR-18 between I-90 and Issaquah Hobart Road depicting the Phases in which improvements will be completed. Phase 1 will be a new interchange between SR-18 and I-90 and is set to begin construction in 2021 with a completion date of 2023. For more information on this interchange please visit WSDOT’s website: https://www.wsdot.wa.gov/Projects/I90/SR18ICImprove/default.htm

While the Issaquah Alps Trails Club fully supports the efforts of WSDOT to improve the safety of the road, there are some important environmental considerations that need to be taken into account. SR-18 passes between Tiger Mountain and Rattlesnake Mountain and runs by Taylor Mountain. These areas are currently home for wildlife including deer, elk, bobcat, cougars, and salmon. Cutting off access between these areas with a larger four lane highway would fragment this critical habitat, severing wildlife populations and increasing the chances of car accidents involving wildlife. Additionally, the area is a popular recreation spot for hiking, biking, and horseback riding. Ensuring safe access for recreation along this highway would help alleviate crowding at other recreation destinations which can damage trails and habitat and promote the area as it develops.

SR-18 crosses key habitat area for a multitude of wildlife including Salmon. Wildlife bridges or under crossings in these four key areas would create connected habitat and decrease road accidents with wildlife. These types of crossings for wildlife have been implemented at Snoqualmie Pass already, with great success.

Key Outcomes

Wildlife connectivity and recreational access should be part of engineering criteria and goals of the project overall. Including these things in the “engineering criteria” or  of the project ensures that they will be taken into account during construction. This means the inclusion of four wildlife undercrossings similar to those found along I-90 at Snoqualmie Pass, added bike access along the road to connect Maple Valley to the Snoqualmie Region by means of green transportation, a “diamond interchange” at Tiger Summit, and intentional redevelopment of Tiger Summit to provide a better wilderness experience at that location.

Milestones

Summer 2019: Washington State Representative Bill Ramos tours the area with key stakeholders

September 2019: Mountains to Sound Greenway Trust writes a letter of support for the project, kicking off the conservation community response 

May 2020: Interviews with stakeholders begin in order to form a strategic plan for the highway in line with the priorities of many who will be impacted. 

June 2020: Advisory Board meetings begin

Call to Action

The Issaquah Alps Trails Club wants to ensure that as this project is done right. We are requesting help in generating support for the inclusion of wildlife connectivity, recreational access, and safety in the engineering guidelines for the project. To do this we need our members and partners to bring this issue up in their communities educate friends, family, and the public about the necessity of these criteria, and reach out to their local representatives. We have included a slide deck below which all are welcome to use to promote this campaign. Please reach out to us at president@issaquahalps.org for more information.

See full project information and IATC’s response here

For more information on the project please visit WSDOT’s website

Read the letter sent by the Mountains to Sound Greenway Trust on the SR-18 Project