The SFMTA plans to install a contra-flow transit lane for three blocks of Sansome Street near the Financial District, providing a faster and more direct route for Muni’s 10-Townsend and 12-Folsom bus routes.

The new southbound lane would be reserved for transit, bicyclists, and commercial vehicles during daytime hours, and eliminate a detour that Muni buses must currently take along Battery Street, one block away. It’s expected to save an average of three minutes for Muni riders, according to Sean Kennedy, planning manager for the SFMTA Transit Effectiveness Project.

The project received preliminary approval at an SFMTA engineering hearing today, and is set to go to the SFMTA Board of Directors for final approval on September 2. It’s expected to be installed by spring 2016.

Currently, the three-block stretch of Sansome between Washington Street and Broadway has two traffic lanes, both one-way northbound, with parking lanes on either side. The project would convert that stretch to two-way traffic, similar to the configuration that already exists on Sansome south of Washington, but the newly-converted southbound lane would be prohibited to cars between 6 a.m. and 8 p.m. every day. All of the existing metered parking spaces on the southbound side would be converted to metered loading zones, according to Kennedy, and most of them would be replaced on cross-streets by converting other loading zones to parking spaces.

The new southbound lane would be similar to the existing part-time lane on the east side of Sansome. On the eastern curb, parking is currently banned between 3 to 6 p.m., when the curbside lane becomes a moving lane for transit and commercial vehicles.

The project will also upgrade the traffic signals along Sansome with transit priority detection, “daylight” some corners, and the crosswalks will be upgraded to “continental” or ladder-style, said Kennedy. American Disabilities Act-friendly curb ramps and blue zones for disabled parking will also be added.