[5] Since the implementation of RapidRide on the corridor, ridership has grown 79 percent and the C Line served an average of 8,300 riders on weekdays in spring 2015.

The two routes were uncoupled during a service change on March 26, 2016, and the C Line was moved onto Westlake Avenue to terminate in South Lake Union, sharing several stops with the South Lake Union Streetcar.

[8] A new C Line stop serving the waterfront, at Alaskan Way and South Jackson Street, opened in February 2022.

[9] The city of Seattle made major improvements to the RapidRide C and D lines with money generated by Proposition 1 (which increases sales tax by 0.1 percent and imposes a $60 annual car-tab fee).

[10] C Line buses now continue north through parts of Belltown and onto transit only lanes Westlake Avenue in the South Lake Union neighborhood,[13] terminating on Valley Street near the Fred Hutchinson Cancer Research Center campus.