ha ha!

I guess the OS must be Vista:

The downtown Seattle bus tunnel is closed because of a failure of the computer system that controls tunnel operations.
....

All of the systems in the tunnel — such as ventilation, lighting and signals — are controlled by a computer system installed during the recent retrofit of the tunnel. That computer system is currently down, and there was not yet an estimate of when it will be restored.

Update: After re-opening for a day, the tunnel was closed again on Wednesday (Dec. 19) and will remain closed at least through Friday. So far, the newspapers have not reported what "computer system problems" entails.