11:01 AM: Metro is rerouting buses onto the 1st Avenue South Bridge right now because of a “mechanical issue” on the West Seattle low bridge – which is closed to all surface traffic. More info when we get it.
12:07 PM: Its status isn’t clear right now – it’s open so a barge can get through, said SDOT director Sam Zimbabwe when we asked for an update before the high-bridge briefing ended, but he believed it would return to normal surface traffic after that. We’ll keep checking.
12:58 PM: Just reopened.
ADDED 4 PM: The reopening happened just as we were being escorted onto the high bridge for photos of the work crew. We also saw this truck backup that built up during the low-bridge closure:
ADDED 6:12 PM: We asked SDOT what went wrong. Their reply:
Operations on the Spokane St Bridge (West Seattle Low Bridge) were interrupted today due to two separate mechanical issues related to the bridge’s hydraulic system and center-locking mechanisms. This incident was unrelated to mechanical issues which affected bridge operations earlier this month, from November 3-5.
At about 11 a.m. this morning, the bridge was swung open to allow a ship to sail through. SDOT bridge operations crews observed irregularities in the bridge’s movement, and discovered a hydraulic fluid leak in one of the pump lines at the West Pier which allow the bridge to swing open and closed (a different pump than the one that was replaced earlier this month). While crews were able to return the bridge to a closed position despite the hydraulic fluid leak, they were briefly unable to open the traffic gates that allows vehicles to use the bridge due to safeguard in the bridge’s center-locking mechanism which was triggered by a faulty mechanical switch which was sending an incorrect signal that the center-lock had not been engaged. Crews were able address the center-lock safeguard and reopened the gate for vehicle traffic shortly before 1 pm.
Since that time, crews have continued to work to double check other bridge systems and repair the hydraulic fluid leak. This work can be done while traffic drives over the bridge. We will only open one leaf of the bridge at a time while these repairs are occurring, but do not expect this to have a noticeable effect on vehicle or ship traffic. We may also perform brief bridge openings to test the systems later this evening, after peak-period traffic is over.