During the recent discussions of Martin’s proposal to improve mobility in the Rainier Valley, one of the central ideas to emerge was redundancy. Transit agencies shouldn’t have routes that compete with each other for the same origin-destination pairs. Whether you agreed with Martin’s proposal or not, it came from his recognition of this type of inefficiency. Services that directly compete with each other for ridership cannibalize their own resources while diminishing productivity, frequency, and connections.
As a postscript to that conversation I’ve often wondered about the utility of Route 4, specifically whether its southern half could be eliminated and its resources distributed elsewhere. Though in 2007 it had the highest ridership per mile of any Metro route, I have a distinct impression that it no longer serves any unique transit market and in fact diminishes the performance of Routes 3, 8, and 48, all of which serve unique destinations. From 3rd/James to 23rd/Jefferson, the shared 3/4 provide 7-15 minute headways until 1am. Once the 4 turns south on 23rd, it duplicates the 48. From its turn at Dearborn it runs in a couplet on 24th and 26th, needlessly threading the needle between 23rd (Route 48) and MLK (Route 8). Worst of all, it inexplicably terminates 1/2 a mile from Mount Baker TC, foregoing any connectivity with Link, the Rainier Valley, and other points south. To serve Mount Baker TC, the only missing infrastructure is either a 1/2 mile of trolley wire along MLK or a left-turn trolley switch at Walker/Rainier.
What market does this route serve that could not be better met by more frequent gridded service? As far as I can tell, perhaps only Judkins Park to Harborview. From its southern terminus to downtown Seattle, Route 7 and Link provide some of the most frequent service in the region. To the Central District, Routes 8 and 48 are faster and twice as frequent. From the Central District to downtown, Routes 3/4 provide peak 7-15 minute headways, or there is half-hourly service on Routes 14 and 27. The 2-4 buses per hour on Route 4 could be used to provide 15-minute headways on both the 14 and 27, or to provide all-day, 7-minute service on Route 3 as far as 23rd, with perhaps every other bus using Route 4’s Queen Anne terminus. Do we need Route 4?