Construction has begun on the East Lake Sammamish Parkway and SE 43rd Way Roundabout Revisions Project. The work will take approximately two months to complete.
June 25-27 Intersection Closure
The City will allow three, full-weekend closures of the intersection. The first full closure will occur June 25-27. This coming weekend, starting at 5 a.m. on Saturday, June 25, 2022, the intersection of East Lake Sammamish and SE 43rd Way will be closed to all through traffic. This closure will be in effect until Monday, June 27, 2022 at 4 a.m. to install critical improvements within the intersection.
Detour Route
During this weekend's closure, cars will be re-routed. Click here for a detailed map of the route. Below is a simplified version of the map.

Other Intersection Closures
The dates for the other two weekend closures have not been determined yet. The City will provide updates and notification before these occur.
During these closures, the intersection will be completely closed to all users, and a detour will be provided through the City of Sammamish. This work is necessary to complete critical components that cannot be completed with single lane closures. Work will be allowed both during the day and night.
Improvements
This project will revise the roundabout to improve safety and mobility for all users. Improvements will include:
- New curb alignments and lane configurations - to reduce traffic speeds through the roundabout
- Paved approach islands – to reduce maintenance efforts and damage occurring within these islands
- Permanent removal of the southbound bypass lane on East Lake Sammamish Parkway and conversion to landscaping – to reduce vehicle merging conflicts
- Rectangular Rapid Flashing Beacons (RFFBs) installed at each crosswalk – to improve pedestrian visibility and awareness
- Radar Speed Signs - to reinforce the recommended 15-mph speed through the roundabout.
- New pavement and striping
Due to the national shortage on electrical components, including RFFBs and radar speed signs, there may be delays to completing some elements of the project within the given window. The majority of the work within the roundabout should not be impacted by any of those delays.
Hours and Impact
Normal work hours will be Monday - Friday, from 7 a.m. - 6 p.m., and will require some single lane closures. You should expect minor traffic delays during working hours. Please be aware of workers near the roadway.
Residents can expect some noise impacts such as engine noise, reverse beepers, and general machinery, as well as flashing lights at night during these closures. Thank you for your understanding.
Contact
If you have questions or concerns with this project, please email Matt Ellis, Senior Utilities Engineer or call 425-837-3410.