Issaquah-Fall City Road Mitigation

Project Overview

This project is located on SE Issaquah Fall City Road between the Duthie Hil Road/Issaquah Fall City Road intersection and the Endeavor Elementary School Driveway. The project will reconstruct approximately one-quarter mile of roadway to address issues of seasonal roadway flooding and improve pedestrian access to the elementary school and nearby parks.

The roadway travels through the bottom of a large topographical depression. During the winter seasons, extended periods of rain saturate the ground and pond in the low-lying area, sometimes causing water to overtop the roadway.

The elementary school and regional park located on the east side of the roadway draw a significant number of visitors from neighborhoods on the west side of the roadway. 

• Timeline: 2024-2027
• Project Status: Design
• Total Funding: $7,100,000

What's the latest?

2024, Quarter 3

Project design, stakeholder outreach and concept analysis.

History and Background

The existing roadway initially started almost one-hundred years ago as a narrow gravel two lane roadway. It now consists of two travel lanes with paved shoulders and non-continuous roadside ditches. In the 1990's it saw additional improvements with development of the Klahanie neighborhood and Endeavor Elementary School. Its current classification is a principal arterial roadway. 

Additional efforts to continue improving the corridor began soon after Sammamish annexed the Klahanie neighborhood and other neighborhoods on the north side of the road (additional annexation information can be found here - City Annexations | Klahanie Annexation | City of Sammamish).

Improvements were split into two phases. Phase 1 extended from Issaquah Pine Lake Road to Klahanie Drive - it was completed in 2021. Phase 2 extended from Klahanie Drive to Issaquah Beaver Lake Road. Design for Phase 2 began in 2020, however, it was paused to work through the Balanced Land Use and Mobility Analysis (BLUMA) and evaluate Capital Improvement Project Funding scenarios.

As a result of the BLUMA, the Phase 2 project is not being advanced for design and construction as a complete project, but as smaller improvements such as a pavement preservation project (summer 2024) and this project. 

Next Steps

The next effort will be to finalize the project concept. Before the Phase 2 project was paused for the BLUMA, the initial concept that was being evaluated for design at this location included sidewalk on one side and signalized intersections at Endeavor Elementary and the Issaquah-Fall City Road Intersection. The project team will pick up where the Phase 2 effort ended to finalize a concept that will be advanced to design.

The concept below is an option that was being considered during the Phase 2. The final option could include roundabouts or a combination of signal and roundabout. The final concept will seek to balance competing community goals to minimize impacts to corridor travel time and preserve trees while improving safety.

Timeline

Funding

This project is currently funded for design. 

Funding Source	Amount ($ in thousands)
King County Flood Grant	$  297
Transportation CIP (340 Fund)	$  255
Surface Water Capital (438 Fund)	$ (Future Funding)
Total Amount Funded	$  552

Amount remaining to be funded: $ 6,549,000

Project Support

This project was designated as a 2024 Legislative Priority (Resolution R2023-1026). In addition to the King County Flood Grant, it has received letters of support from:

1. Endeavor Elementary Parent Teacher Student Association
2. Eastside Fire and Rescue
3. Issaquah School District
4. King County Council Member Sarah Perry (District 3)