Stephanie served as the lead roadway engineer and design manager for the interchange of SR 518 and Des Moines Memorial Drive. This work included designing a new eastbound SR 518 off-ramp and realigning the eastbound SR 518 on-ramp developed by WSDOT in the 2010 Route Development Plan. As the roadway manager, Stephanie led the geometric design of the WSDOT Interchange Justification Report (IJR), which included eight ramp design alternatives at the interchange. Her work also included WSDOT Channelization Plans for Approval, Design Variances, and a Practical Design Analysis. The project includes a new bridge over 8th St SE, significant retaining walls, and minimizing right-of-way impacts to adjacent contaminated soils, with multi-agency coordination among the Port of Seattle, Department of Ecology, Seattle Public Utilities (SPU), the City of Burien, and WSDOT.
The City of Burien led the project from preliminary design to the 90% design level; once the project received legislative funding from the Connecting Washington Package, WSDOT became the owner. In 2017, Stephanie completed a BRT Capacity Alternatives Assessment for WSDOT to be forward-compatible with future ST3 plans. Her tenure on the project concluded after providing services during construction.