Why is light rail being considered on I-90 instead of SR-520?
There are several reasons why I-90 works more effectively than SR 520 for an initial cross-lake light rail line. I-90 was built for use as a High Capacity Transit facility, and already has a direct connection into the Downtown Seattle Transit Tunnel where it will connect with the Central Link light rail line. The SR 520 alternative, on the other hand, presents both design and operating challenges. For example, there would be significant challenges connecting a surface rail line from SR 520 to the underground University Link light rail line that is being built from downtown Seattle north to the UW and eventually Northgate and into Snohomish County. The connections would have to be in an underground ‘merge’ of the rail lines or by building a separate right-of-way for the eastside line into downtown Seattle. Both of those choices would be very expensive and difficult to construct. In addition, because the Link line between downtown Seattle and Northgate will carry a large number of passen
