Metro Transit buses probably will leave the Downtown Transit Tunnel when light rail reaches the University of Washington in 2016. But there are conflicts already evident as buses and trains share the tunnel now -- a system unique to Seattle -- and that's not good for maintaining timely arrivals of Seattle's shiny new light rail.
The writers at Seattle Transit Blog engaged in a good debate with Metro's General Manager Kevin Desmond about whether it's time for fewer Metro buses to run through the downtown tunnel.
Buses were there first and have shared the tunnel since light rail opened last summer. But every time a bus breaks down or is delayed to pick up a wheelchair-bound passenger inside the tunnel, it affects Link light rail's reliability (which happened 15 times in May due to mechanical issues, according to Desmond). Then again, buses, which haul more passengers than light rail, also occasionally have to wait for trains to clear.
Martin H. Duke, the blog's editor, wrote Tuesday that it might be time to reduce the number of buses in the tunnel to the point that they don't affect the light rail's schedule.
"There's always a tradeoff between letting more riders benefit from the tunnel and diluting that benefit by putting in too many buses. Before there was Link, not every bus that could use the tunnel did so. Today, trains occupy a large amount of the capacity. What's different, though, is that given a multibillion dollar investment in reliability, expectations are higher. Someone interested in its success, and presumably Desmond is, should be looking for ways to remove obstacles to its smooth operation."
Desmond wrote his own piece this week in the blog summing up why joint operation between buses and trains makes the most use of the tunnel capacity. His strongest point: Buses take 50,000 weekday boardings just inside the tunnel. The entire Link light rail system averages around 21,774.
"A rail-only tunnel would improve Link reliability, but then again the tunnel would be very under-utilized. Joint operations helps both Metro and Sound Transit move thousands of people each day through downtown Seattle without adding additional congestion to the surface streets."
"So while Link service would be more reliable if it was exclusively for trains, we would see increased travel time for thousands of Metro and ST bus riders, and increased operating costs for both KCM and ST due to lengthier bus travel times through downtown."