SR 167 Completion Project – What is a diverging diamond interchange?

A diverging diamond interchange is a type of interchange design where traffic crosses to the left side of the road between highway ramps to eliminate left-turns across oncoming traffic. Diverging diamond interchanges reduce delays and collisions.

Travelers can use new through-lanes, and SR 167 on- and off- ramps on the future North Meridian diverging diamond interchange when the stage 2a project is complete in 2027. Additional SR 167 connections will open to travelers in 2029 following completion of the stage 2b project.

There’s not much new to learn about how to drive in a diverging diamond interchange. Clear striping, signing and traffic signals will help route drivers through the interchange using the same rules of the road that operate everywhere in Washington.

Diverging diamond interchange design benefits

Improved safety: A diverging diamond interchange reduces the number of vehicle conflict points, where vehicles cross or merge which reduces the risk of collisions.
Increased efficiency: The crossover intersections can be maneuvered with fewer traffic signal phases, allowing traffic to cross the intersection more frequently and reducing wait times and delay.
Easier access to the expressway: Traffic entering and exiting the freeway no longer has to cross opposing lanes of traffic.
Cost effective: The design requires a smaller footprint to build which can reduce costs in comparison to a different intersection type that might require larger structures or additional roadway space.

How will drivers use the new diverging diamond interchange at SR 167 and SR 161/North Meridian Avenue in 2027?

The SR 167 stage 2a project will build the future diverging diamond interchange at SR 161/North Merdian Avenue in Puyallup. WSDOT will be conducting a robust outreach and public education campaign to make sure Washington drivers are ready when the new interchange opens to traffic. In the meantime, the following diagrams help describe how the interchange will work when it starts partial operations in fall 2027.

North from Puyallup toward Edgewood and Milton

Motorists can travel north on North Meridian Avenue from Puyallup toward Edgewood/Milton using the center through-lanes of the new North Meridian Avenue interchange.

South from Edgewood and Milton toward Puyallup

Motorists traveling south on North Meridian Avenue from Edgewood and Milton will use either the center or right lane heading toward Puyallup.

Northeast from Puyallup toward Sumner

Drivers travelling from Puyallup toward Sumner will use the right lane to access the on-ramp to northbound SR 167.

Southeast from Edgewood and Milton to Sumner

Drivers traveling from Edgewood and Milton toward Sumner will use either the center or left lane to access the on-ramp to northbound SR 167.

Southwest from Sumner toward Puyallup

Drivers exiting southbound SR 167 to downtown Puyallup will use either of the left lanes.

Northwest from Sumner toward Edgewood and Milton

Drivers exiting southbound SR 167 toward Edgewood and Milton will use either of the right lanes.

When the new SR 167 Expressway west of North Meridian Avenue opens to traffic in fall 2029 (stage 2b), WSDOT will open the full diverging diamond interchange at SR 167 and SR 161/North Meridian Avenue, including the following connections:

southbound SR 161/North Meridian Avenue to southbound SR 167
southbound SR 161/North Meridian Avenue to northbound SR 167
northbound North Meridian Avenue to southbound SR 167
northbound North Meridian Avenue to northbound SR 167
southbound SR 167 to southbound North Meridian Avenue
southbound SR 167 to northbound SR 161/North Meridian Avenue
northbound SR 167 to southbound North Meridian Avenue
northbound SR 167 to northbound SR 161/North Meridian Avenue
thru-traffic on SR 161/North Meridian Avenue