I-5, SR 502 Interchange Design
Click to enlarge map. (high resolution, 205 kb)
The option selected (Option M, for "modification") combines elements from two of the final desings (Option E-4 and Option C), and is considered the best Recommended Build Alternative. A detailed study to determine the alignment that would have the least environmental impact began in Sept. 2004. Through that study, a new northbound loop ramp was identified that is more environmentally friendly, impacts fewer property owners, and will save taxpayers $1 million.
Option E-4 was initially selected as the recommended build alternative in March 2004 following extensive public involvement and two levels of evaluation. Since that time, WSDOT added a loop ramp to southbound I-5 to the design. The next, more detailed step in the evaluation process identified environmental concerns and the need for additional land for the project. These new considerations made Option E-4 more comparable to the previously considered Option C. Option C was the only other option that passed the earlier two evaluation steps. The variations of Option M presented this summer are modifications of Option C.