City of Burien
SW 148th Street
4th Ave SW to 6th Ave SW
TIB Award Amount
$3,932,160
Region: Puget Sound   |   Legislative District: 34   |   Length: 0.20 mi. FY 2024 Urban Arterial Program (UAP)

Project Information

Agency Name City of Burien
Funding Year FY 2024
Program UAP
Legislative District 34
Congressional District 7
Federal Route Number 1350
Project Length 0.20 mi.
ADT 14,260
Functional Class Principal
Type of Work
Project Contact Robin Tischmak
Contact Email robint@burienwa.gov

Project Schedule

Milestone Target Date
Environmental Documentation Complete & Permits Approved 04/13/2015
Right of Way Acquisition Complete 04/01/2023
Design Start  
Construction 10/31/2016
Contract Award 06/30/2023
Project Closeout 12/31/2024

Existing Conditions

This project will improve safety and mobility for multiple users and functions. SW 148th St is an important principal arterial that is critical to serving residents and destinations within the Burien Regional Growth Center as well as the surrounding community. The Burien Transit Center, Burien Community Center, new and growing multifamily residential units, Burien City Hall, King County Library, King County Courts, local businesses, and the Burien Downtown all surround this project and rely on SW 148th St for safe, reliable access and circulation. Localized vehicle capacity improvements are needed on 4th Ave SW approaching SW 148th St from the south to improve the level of service and to allow for future growth. Traffic signal upgrades and improvements are necessary for safety to reduce/eliminate right-angle collisions and to improve the operational efficiency/capacity for vehicular traffic. Pedestrian improvements and upgrades are necessary to increase safety for non-motorized users that access the numerous destinations listed above. Improvements will include ADA-compliant curb access ramps, updated pedestrian signal components, and enhanced lighting. The replacement of the existing pedestrian signal at 6th Ave SW with a fully-actuated traffic signal will improve safety and efficiency for all modes of travel.

Project Funding

  TIB Funds Local Funds Total Costs
Design 0 0 0
Right of Way 0 0 0
Construction 3,932,160 983,040 4,915,200
Project Totals $3,932,160 $983,040 $4,915,200

Local Match

TIB Participation Local Match Minimum Local Match
80.0% 20.0% 20%

Description of Improvements

This project includes widening northbound 4th Ave SW to add a dedicated right-turn lane at SW 148th St, replacing the existing traffic signal at 4th Ave SW, and constructing a new traffic signal at 6th Ave SW. The new right-turn lane will provide the current and future capacity needs for 4th Ave SW approaching SW 148th St. The existing traffic signal at SW 148th St/4th Ave SW does not provide protected left-turns for any leg of the intersection and numerous right-angle accidents are a result. The north/south legs are operated with split phases, which reduces accidents but decreases operational efficiency. A new traffic signal will correct these existing deficiencies and will provide technological upgrades for pedestrian amenities. Curb access ramps will be reconstructed to meet ADA compliance. A new traffic signal at SW 148th St/6th Ave SW will replace the existing pedestrian signal crossing SW 148th St. Visibility of the pedestrian signal from 6th Ave SW is limited and all pedestrian crossing legs will be made safer with a standard traffic signal. Vehicular traffic will have improved safety with controlled movements and dedicated left-turning phases. The existing limited lighting on SW 148th St will be improved with new luminaires installed on pedestrian poles and all new traffic signal poles.