HOV Lanes, Tunnels to Speed Flow : Transportation: Freeway improvements and construction of the MTA subway are priority projects for 1996.

Diamonds and digging are in store for San Fernando Valley commuters in 1996, as transportation officials strive to improve the area’s flow of traffic.

Most visible will be the construction of new carpool, or “diamond” lanes for four freeways:

* On the San Diego Freeway, northbound and southbound high-occupancy lanes will open late in the year between the Ventura Freeway and the Simi Valley Freeway.

* On the Hollywood Freeway, carpool lanes will extend from the Ventura Freeway north to the Golden State Freeway.

* On the Antelope Valley Freeway, carpool lanes will run north first from San Fernando to Sand Canyon, then extend to Escondido Canyon. Construction is scheduled to start in the spring and finish in 1998.

* On the Simi Valley Freeway, high-occupancy lanes will reach from the Ventura County line to the Golden State Freeway. Those are scheduled to open in December next year.

In addition, Caltrans workers will begin widening California 126 in August in the Val Verde area from the Ventura County line to the Golden State Freeway.

Below ground, a Metropolitan Transportation Authority contractor will begin digging twin tunnels for the Red Line subway segment from Universal City to Hollywood in late February. A spokesperson said that if explosives are used to create cross-track passages and underground equipment rooms, the blasting could start as soon as June.

Farther north, excavation for the Red Line tunnel from North Hollywood to Universal City is expected to conclude in the summer.

Above ground, the MTA said construction of its Universal City subway station will begin by the end of March. The station is scheduled to be ready for use early in the next century.

As for rail riders, Metrolink spokesperson Charlene Ariza said no new stations are planned for 1996.

But she said a rapid rise in ridership has increased crowding on the line, so the agency does plan to lease a few new cars during the year.