Washington State
Transportation Center (TRAC)
TRAC-UW
1107 NE 45th St
Seattle, WA 98105
Phone: 206.543.8690
Fax: 206.685.0767
TRAC-WSU
Sloan Hall, Room 101
PO Box 642910
Pullman, WA 99164-2910
Phone: 509.335.3175
Fax: 509.335.7632
WSDOT Research Office
Transportation Building
Washington State
Department
of Transportation
310 Maple Park Avenue SE
PO Box 47300
Olympia WA 98504-7300
Phone: 360.705.7000
Directions to I-405 South of I-90 Sites:
I-405
@ Tukwila Parkway (near Southcenter)
I-405 @ 112th SE (Newcastle)
From southbound I-5, take the Southcenter Boulevard exit. Turn left at the stoplight at the end of the ramp, and stay in the far left lane. Continue straight through the first two stoplights. Turn right on Tukwila Parkway/ Christianson/68th. Park in the public parking area behind the gas station at the bottom of the hill. Walk up the sidewalk to the overpass. To count Northbound traffic you will need to sit behind the guardrail as there is no sidewalk on that side. To count Southbound traffic, place your chairs on the sidewalk above the southbound lanes. Wear your safety vest at all times.
If approaching from southbound I-405, take the West Valley Highway/Interurban Avenue South exit. The exit ramp will curve around to the right. At the stoplight, turn left and stay in the left lane. Turn left again at the next stoplight onto Southcenter Boulevard. Go several blocks to the first street on the left, and turn left on Tukwila Parkway to park in the public parking area behind the gas station.
Wear your safety vest at all times.
I-405 @ 112th SE: Directions to I-405 at 112th Ave SE (Newcastle):
From the office enter I-5 Southbound at NE 45th St. Going south on I-5 exit to I-90 Eastbound. From I-90 exit to SR 167 Southbound.
From southbound on I-405, take exit #9, 112th Ave. SE. There is a Park n Ride lot on the northeast corner of this interchange where you can park, or you can park behind the bus kiosk at the northwest end of the overpass.
Note: There is no sidewalk on the north side of the overpass. When counting AVO mainline traffic southbound you must wear a vest. Place your chair on the shoulder of the north side of the street. To count northbound vehicles sit in your chair on the sidewalk on the south side of the overpass.
Count the buses that get off the freeway to pick up or to drop off passengers in both Northbound and Southbound directions as Lane #1 traffic.
Wear your safety vest at all times.