I-405/SR 167 Corridor Program


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What is the long-term plan for I-405/SR 167?
Interstate 405 is one of the state's most congested corridors. For more than two decades, WSDOT has worked with cities, counties, federal agencies, transit agencies and community groups to develop consensus on a long-term vision for the multimodal redevelopment of this highway. 

This effort culminated in a three-year environmental impact statement (EIS) development process that outlines a balanced approach to transportation, including a blend of transit, roadway, non-motorized and environmental investments. The EIS, approved with the Record of Decision in October 2002, now serves as the corridor Master Plan.

Major features of the Master Plan include two new lanes in each direction, a managed lanes system, local street improvements, transit improvements (including a new Bus Rapid Transit system), and bicycle and pedestrian improvements. 

WSDOT continues to work with local communities and transit agencies through our I-405/SR 167 Corridor Executive Advisory Group to improve I-405/SR 167 within available funding. 

What has the I-405/SR 167 Corridor Program accomplished to date?
Since the master plan for I-405 improvements was adopted, we have focused on building groups of projects that directly address the worst congestion chokepoints first, coordinating all transportation modes into a working system.

WSDOT has now delivered all 15 construction projects for the I-405/SR 167 corridor funded by the 2003 Nickel, 2005 Transportation Partnership Account, and Connecting Washington funds, with nearly $1.5 billion in investments throughout the corridor all on time and on budget.

Highlights include the I-405/SR 167 Interchange Direct Connector Project, which opened to the public in February 2019 and was the first project in the corridor to be constructed with Connecting Washington funding. In April 2017, WSDOT opened a new northbound peak-use shoulder lane on I-405 between SR 527 and I-5, which represents the first reinvestment of I-405 Express Toll Lanes revenue back into the corridor.

What are our next steps for the I-405/SR 167 corridor? 
In 2015, the Legislature funded about $1.3 billion of new investments in the corridor through the Connecting Washington package. Several of these projects are well under way, including: 

WSDOT is also partnering with Sound Transit to deliver the new I-405 Bus Rapid Transit system, with a scheduled opening date of 2025. I-405 BRT is a new high-capacity transit service providing fast, frequent and reliable bus connections along I-405 and SR 518 from Lynnwood to Burien with a new transit center in South Renton and 11 BRT stations, three of which will include added parking. Buses will travel primarily in the managed lanes to increase speed and reliability.