Cone Zone 10/31/2025: Sammamish Traffic Updates
Release Date: 10/31/2025
Louis Thompson Intersection Paving & Detour Limits
🕤 Detour limits change October 30:
🚦 Beginning October 30, the one-way detour on Louis Thompson Road will be shortened to include only the segment between 208th Avenue NE and East Main Street.
📍Local access:
- Residents traveling as far up the hill as 208th Avenue NE will be able to drive downhill during this modified detour through November 21.
- Residential locations uphill from East Main Street can be accessed coming down the hill.
👷♂️ This temporary traffic change is necessary to safely construct Walls 7 and 8 along the uphill lanes. Please see the project page at this link, below, for ongoing updates: www.sammamish.us/projects/louis-thompson-tightline
247th Ave SE Catch Basin Replacement Project
🕤 November 3 - November 21
🚦Traffic Impacts: Temporary lane shifts, short-term driveway access impacts, construction equipment in roadway, and intermittent traffic control. Local access will be maintained.
📍 Work Location: Along 247th Ave SE (see below)
👷♂️ This work is to replace a damaged catch basin and install a new drainage structure. One adjacent tree causing root damage will be removed as part of this work in order to prevent future infrastructure impacts.
Watermain Installation
🕤 August 2025 – December 2025
🚦 Traffic Impacts: Traffic control is being used and some minor delays are expected.
📍 Work Location: NE 36th & NE 37th off Sahalee Way
👷♂️ Northwest Sammamish Water & Sewer will be installing a new water main.
PSE Gas Main Replacement
🕤 October 6 – December 31, 2025, 7:00am – 4:00pm. In addition to week days, expect work to occur on some Saturdays as well.
🚦 Traffic Impacts: Traffic control will be used with minor delays.
📍 Work Locations:
📌 224th Pl NE between NE 16th St and NE 14th Drive
📌NE 14th Drive between 220th Pl NE and 225th Ave NE
📌NE 14th Drive between 225th Ave NE and 228th Ave NE and NE 12th Pl
👷♂️ PSE crews will be doing asphalt patches. This work will be followed by grid and overlaying on some streets. Lakeside will also be raising utilities in the road beginning October 7th and will be working throughout the week.