<P> The second freeway HOV facility was the contraflow bus lane on the Lincoln Tunnel Approach and Helix in Hudson County, New Jersey, opened in 1970 . According to the Federal Highway Administration (FHWA), the Lincoln Tunnel XBL is the country's HOV facility with the highest number of peak hour persons among HOV facilities with utilization data available, with 23,500 persons in the morning peak, and 62,000 passengers during the four - hour morning peak . </P> <P> The first permanent HOV facility in California was the bypass lane at the San Francisco--Oakland Bay Bridge toll plaza, opened to the public in April 1970 . The El Monte Busway (I - 10 / San Bernardino Freeway) in Los Angeles was initially only available for buses when it opened in 1973 . Three - person carpools were allowed to use the bus lane for three months in 1974 due to a strike by bus operators, and then permanently at a 3 + HOV from 1976 . It is one of the most efficient HOV facilities in North America and is currently being converted into a high - occupancy toll lane operation to allow low - occupancy vehicles to bid for excess capacity on the lane in the Metro ExpressLanes project . </P> <P> Beginning in the 1970s, the Urban Mass Transit Administration recognized the advantages of exclusive bus lanes and encouraged their funding . In the 1970s the FHWA began to allow state highway agencies to spend federal funds on HOV lanes . As a result of the 1973 Arab Oil Embargo, interest in ridesharing picked up, and states began experimenting with HOV lanes . In order to reduce crude oil consumption, the 1974 Emergency Highway Energy Conservation Act mandated maximum speed limits of 55 mph (89 km / h) on public highways and became the first instance when the U.S. federal government provided funding for ridesharing and states were allowed to spend their highway funds on rideshare demonstration projects . The 1978 Surface Transportation Assistance Act made funding for rideshare initiatives permanent . </P> <P> Also during the early 1970s, ridesharing was recommended for the first time as a tool to mitigate air quality problems . The 1970 Clean Air Act Amendments established the National Ambient Air Quality Standards and gave the Environmental Protection Agency (EPA) substantial authority to regulate air quality attainment . A final control plan for the Los Angeles Basin was issued in 1973, and one of its main provisions was a two - phase conversion of 184 mi (296 km) of freeway and arterial roadway lanes to bus / carpool lanes and the development of a regional computerized carpool matching system . However, it took until 1985 before any HOV project was constructed in Los Angeles County, and by 1993 there were only 58 mi (93 km) of HOV lanes countywide . </P>

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