Planning A 1993 AC Transit study designed the Berkeley–Oakland–San Leandro corridor as a potential alignment for major transit investment. The 2002-released MIS recommended
bus rapid transit (BRT) for the corridor;
light rail was deemed not to be cost-effective, while enhancements to conventional bus service would not generate significant ridership increases. Prior to 2007,
Telegraph Avenue was primarily served by the 40/40L local/limited-stop routes, while
International Boulevard and East 14th Street were served by the 82/82L pair. Service changes on June 24, 2007, included the establishment of Berkeley–Downtown Oakland–Bay Fair routes 1R and 1; the 82/82L were discontinued and the 40/40L were cut back to no longer serve Telegraph Avenue. Route 1R (the International Rapid) operated as a limited-stop overlay of local route 1; it had some
bus rapid transit features like
transit signal priority and wide stop spacing, but not all-door boarding or dedicated lanes. It was intended as a first phase while the full BRT service was planned. In April 2010, the Berkeley City Council voted against the inclusion of center bus lanes over concerns about reducing Telegraph Avenue to a single general traffic lane in each direction. The city's preferred alternative, with curbside stops and no dedicated bus lanes, was not compatible with BRT service standards. Berkeley withdrew from the project in 2011. San Leandro also objected to center lanes on its portion of the line. The Final Environmental Impact Statement/Final Environmental Impact Report, released in January 2012, removed the center lanes south of Georgia Way in San Leandro. It also included a Downtown Oakland–San Leandro alternative to allow the project to proceed without the Berkeley and North Oakland section. AC Transit approved this shorter alternative in April 2012, followed by the Oakland and San Leandro city councils that July. (That June, the center lanes had been further cut to Broadmoor Street near the Oakland/San Leandro border by the San Leandro city council.)
Construction and service Route 1R was eliminated on June 26, 2016 to allow for construction. Route 1 was changed to run only between Downtown Oakland and San Leandro station; new routes 6 and 10 were created to serve the Downtown Oakland–Berkeley and San Leandro–Bay Fair segments. Groundbreaking was held in August 2016. The project was funded by a mix of local, state, and federal funds; major sources included
Federal Transit Administration Small Starts (31%), Regional Measure 2 bridge tolls (24%), AC Transit (10%), and Alameda County Measure B/Measure BB sales tax (9.2%). The service was branded Tempo in July 2020, with the service numbered 1T. Route 1T service began on August 9, 2020, with local route 1 eliminated. Tempo was fare-free for the first 90 days of service; fare collection started on November 9, 2020. The total cost of the project was $232 million. On August 6 of the same year, late-night trips (after 9 pm) were also truncated in the same way. In 2024, a "quick build" project by AC Transit and the City of Oakland added
delineator posts, pavement markings, and signage between 14th Avenue and 107th Avenue in response to safety concerns.
Speed cushions to discourage motorists from illegally driving in the bus lanes were also planned. A 2016 AC Transit study of potential improvements to major corridors proposed extensions of the Downtown Oakland–San Leandro corridor to Emeryville via West Grand Avenue, and to Bay Fair station via East 14th Street. ==Station list==