SDOT: Improvements at 1st/Denny to speed QA, Magnolia, Ballard routes

SDOT Blog announced more upcoming transit improvements around 1st/Denny. They will:

  • Add a signal phase that allows left turns to Denny from northbound 1st Avenue’s right-side bus lane. This will allow outbound Magnolia routes and Ballard expresses to use the bus lane all the way to the intersection instead of merging into the often congested general-purpose lanes to turn left. Details of the signal phase are not given, but there’s precedent for short, vehicle-actuated queue jump phases in similar situations throughout Seattle. The biggest question I have (as someone that doesn’t ride through here regularly) is whether more advanced detection is needed at this intersection, to check whether multiple buses need to get into the intersection. When the 44 bunches (or when the 44 and 16 go through 45th/Wallingford together) its queue-jump signal phases aren’t long enough for both buses to get through. When it’s two buses on the same route giving the first a head start doesn’t matter much (the second, emptier bus will catch back up to the loaded first bus within a few stops), but this turn serves five different routes.
  • Move the bus stop just after this left turn west, to make more room when multiple buses approach the stop. The need to do this suggests that multiple buses indeed go through the left turn together often.
  • Extend bus lane hours on northbound 1st approaching Denny. Currently it’s open for a few hours in the evening peak. A few hours in the morning peak will be added as well. This is good news as it helps out the D Line and all-day Queen Anne routes making counter-peak trips. It’s not quite the all-day bus lanes requested here, but it’s an incremental step.

Investments at this intersection suggest SDOT isn’t imminently planning to let northbound buses turn left from 3rd to Denny, for better or worse. I haven’t seen any exact dates, but the blog says “complete by fall 2014”.