OAKLAND, Calif. (KRON) -- A six-month-long construction project began on Monday to convert the far left lane of westbound Interstate 580 to a high occupancy vehicle (HOV) carpool and bus lane. The construction zone stretches from the Piedmont Avenue undercrossing in Oakland to the start of the exi sting carpool lane near the foot of the MacArthur Maze, Metropolitan Transportation Commission (MTC) officials said. The 2.3-mile project "is a key element of MTC’s Bay Bridge Forward initiative ... to help move more people in fewer cars through the Bay Bridge corridor; speed travel times, and improve schedule reliability for bus riders," transportation officials wrote. Beginning on Monday, April 20, drivers headed westbound on I-580 will see crews installing concrete K-rails to protect workers and equipment from moving traffic, MTC officials said. How much money has each 2026 California governor candidate raised? Construction work will take place primarily during overnight hours, and drivers will encounter night-time lane closures during the next few months. The project is scheduled to be completed this fall. Once construction is finished, using the left lane in this segment of westbound I-580 will be restricted to buses and other vehicles with three or more occupants on weekdays, from 5 a.m. to 10 a.m., and from 3 p.m. to 7 p.m., according to MTC. ...read more read less