SAN DIEGO (CNS) - Two major San Diego-area freeway projects will be started, and a third will be completed, over a one-month span this spring, Caltrans announced Thursday.

In March, work will begin on a $67.2 million project on the 805 freeway in the Sorrento Valley that will add carpool lanes - and on-ramps directly to the carpool lanes - from Carroll Canyon Road, Laurie Berman, director of the San Diego district for Caltrans, said at a news conference.

The direct access to the carpool lanes will be especially helpful for commuters, because "when you get on the freeway you won't have to get all the way over" to the center, Berman said.

During construction in an area where about 300,000 cars pass every day, the lanes of the 805 might be narrowed, but none will be taken away during the day, said Allan Kosup of Caltrans.

"Closures will be done at night," Kosup said.

Berman said that when the project is complete next year, the carpool lanes along the coast will extend for 10 miles from Mira Mesa Boulevard on the 805 freeway to Manchester Avenue on Interstate 5.

Also in March, the extension of state Route 52 from state Route 125 through Santee to state Route 67 is scheduled to open. The specific date is unknown.

In early April, construction is to begin on a new interchange for the 805 connection with state Route 905 near the International Border.

New freeway lanes will also be added to the 905.

Caltrans has a total of 24 projects in San Diego County scheduled this year, ranging fromĀ  freeway construction to replacing the restrooms at the Buckman Springs Rest Stop along Interstate 8 in the East County mountains.

Scheduled to be completed later this year is the addition of carpool lanes on Interstate 15 in Escondido, so cars carrying two or more people, or buses, will be able to travel on them from before the state Route 163 merge all the way to Highway 78.