Mark your calendars for July 21. That’s the date that Convention Place Station will close permanently, heralding the upcoming end of bus service through the downtown transit tunnel.

As we mentioned last month, buses will access the tunnel using a temporary ramp from 9th Avenue between Pine Street and Olive Way. The ramp is nearing completion and the adjacent bus stops, located on 9th Avenue on the north side of Pine Street, will be installed in the coming weeks.

After the changeover takes effect, all seven bus routes in the tunnel will use these two bus stops, eliminating the long-standing tradition of spotting the next inbound bus from the mezzanine level before rushing down the stairs to one of three bays. According to Metro’s Jeff Switzer, the new stops will appear as time points in GTFS data (including One Bus Away) in early August and on printed timetables in September, but until then we can use the 3-to-5 minute delay for peak trips spelled out by the convention center environmental review.

To reach the tunnel, peak-direction buses coming from the I-5 express lanes (routes 41 and 74) will continue further down the Pike express lane offramp and turn north onto 9th Avenue. Buses exiting the tunnel (routes 101, 102, 150, and 550) will simply turn out onto 9th Avenue before continuing two blocks south to several layover spaces on Convention Place between Pike and Union streets.

Buses using the general purpose lanes on I-5 (routes 41 and 255) will turn south from Stewart onto Boren (instead of 9th), then take a right turn onto Pine Street and another right onto 9th Avenue to reach the inbound bus stop, which involves three more turns than the existing routes. When traveling outbound, these buses will travel east onto Pine, north onto Bellevue Avenue, and then cut west across Olive Way to reach the I-5 ramp, in a manner similar to Route 545’s peak-hours Capitol Hill diversion—sans the extra stop on Bellevue Avenue.

With the ramp in place and buses moved aside, Convention Place Station will be demolished to make way for the subterranean exhibition hall that will someday host beloved megaconventions like PAX and Emerald City Comic-Con. The convention center will take full possession of the property by March 2019, assuming that it reaches a September milestone set by the county for the start of demolition. Sound Transit will take over operations of the tunnel sometime after March 2019, bringing with it a full transition to rail-only operations for the first time in the tunnel’s 28-year history.