Our Projects

SR 161 Corridor Analysis between 8th St E/Milton Way and 36th St E, Edgewood, WA. This project involved an extensive traffic forecast and design analysis of 5 alternative corridor designs along the to-be-widened section of SR 161. The base WSDOT design called for a typical 5-lane section, whereas William Popp Associates reviewed alternative designs that would minimize project impacts. The analysis included development of long range (25-year) traffic forecasts post-processed based on existing traffic counts and the Pierce County model, incorporated surrounding major WSDOT highway project assumptions, development of a local area model windowed out from the County model with extensive zone expansion and future land use updates based on the Edgewood Comprehensive Plan, and development of AM and PM peak hour turning movements at 15 signalized and unsignalized intersections. Intersection improvements included review of modern roundabout designs as part of an effort to enhance community acceptance. The final stage of the analysis included AM and PM peak hour Syncho runs and SimTraffic runs (existing plus 5 alternatives for both peak hours) to estimate intersection and system delays, speeds, LOS, with particular focus on queuing at signalized intersections.

I-5/Labree Road New Interchange Study and I-5/North County Line New Interchange Study, Lewis County, WA (two congruent studies). As a subconsultant to Harding Lawson Associates, WPA prepared exhaustive individual intersection level of service analyses (using HCM), coordinated systems analyses (using Transyt-7f), and queue length analyses for existing conditions, year of opening conditions, and 20-year forecast conditions four existing interchange systems and two proposed interchange projects. Analyses were for both the AM and PM peak hours, for conditions with and without the interchange improvements which assumed varying degrees on property development with the two scenarios. Also, dueto extensive industrial areas, all analyses considered the significant truck impacts and calibrated results based on such. In all, over 160 intersection analyses at 22 different intersections and over 35 Transyt-7f analyses at 5 different locations were conducted. Summary of findings included LOS conditions and mitigation requirements and intersection queue lengths for all movements. Furthermore, assisted the WSDOT in analyzing roundabout alternatives to alleviate queuing at closely spaced intersections and ramp terminals.

Pacific Avenue SE/Lacey Boulevard One-Way Couplet Analysis, Sleater Kinney to Carpenter Rd, Lacey, WA. Study implemented 20 year PM peak hour traffic forecasts, identified necessary lane requirements and intersection deficiencies, looked at alternative and do-nothing scenarios, identified operational and safety improvements. Prepared planning level cost estimates for each alternative.

Mallon Street Extension Alternatives Analysis, Howard to Washington, Spokane, WA. Study prepared 20 year PM peak hour traffic forecasts, identified necessary lane requirements and intersection deficiencies, looked at alternative and do-nothing scenarios, identified operational and safety improvements.