The last day of trolleybus operation in the tunnel was January 24, 2005, with only a single dual-mode bus in service on the final day. In February 2004, Sound Transit announced that it would begin the closure and renovation of the bus tunnel in September 2005, two years earlier than scheduled, to save money and reduce construction delays. Construction of a stub tunnel under Pine Street near Convention Place station, to be used for light rail train storage and turnback, as well as a future extension to Capitol Hill, began in January 2005. The bus tunnel was closed on September 24, 2005, moving the tunnel's 21 routes and 140 buses per hour to surface streets. 3rd Avenue was converted to a "transit-priority corridor" during peak periods, restricting general traffic to one-block travel. The $82.7 million construction contract for the transit tunnel renovation was awarded to Balfour Beatty in August 2004, 12 percent below Sound Transit's estimates. The majority of the cost was paid by Sound Transit and supplemented by $8.1 million from King County Metro. As part of the renovations, the tunnel's roadway was lowered by to allow for level boarding, required by the Americans with Disabilities Act; as a result, Metro added strobe lights to bus mirrors, which were lowered to head height, and added warning signs. New electrical, mechanical, and emergency systems were installed, along with a new communications system connecting to a joint-operations center. The project ended up costing $94 million in total, 3.4 percent over the budget set in 2004. During the closure, Metro found that average travel time through downtown increased only 11 percent during the afternoon peak period, and ridership on popular routes only dropped slightly. Joint bus and train operations The tunnel reopened to service on September 24, 2007, with tunnel routes modified to group common destinations together. Initially, the reopened tunnel was in use only on weekdays, with Saturday operation not yet reinstated. Stations were given new entrance signs, lighting fixtures, electronic passenger information signs, and restored paint. The peak bus-only restrictions on 3rd Avenue remained in place after the reopening, along with the skip-stop service that Metro implemented on the street. The tunnel was temporarily closed for nine days in December after a computer glitch disrupted the tunnel's new emergency-control system, which was repaired and replaced. The tunnel had remained closed on weekends after its reopening, but Saturday operation was reinstated