Safety is expected to improve for westbound bicyclists on Alpine Road as they pass under Interstate 280, but the $175,000 needed to create a green-colored bike lane in that spot's complex flow of traffic won't be coming from the agency usually associated with county highway projects -- the San Mateo County Transportation Authority.

"I don't have the details, but I can tell you it will get done," Supervisor Don Horsley told the Almanac. "For whatever reason, (the agency board) decided to get the California Department of Transportation to do it." Mr. Horsley is a board member but said he was absent on Oct. 4, the day the board allocated project funding from its $83 million budget for the 2012-13 budget year.

Mr. Horsley represents Portola Valley and the unincorporated area of Ladera and Stanford Weekend Acres. An improved bike lane under the freeway became a priority after a westbound cyclist from Los Altos Hills died in that area in a November 2010 collision with a tractor-trailer truck.

The seven-member Transportation Authority board did authorize 23 projects, all funded at least in part from half-cent sales tax revenues dedicated to county transportation projects.

Included among the authorized projects were two in Menlo Park:

■ Spending $500,000 for "interchange improvements" at U.S. 101 and Willow Road.

■ Spending $1.3 million on construction along Sand Hill Road between Santa Cruz Avenue and Interstate 280 for "traffic signal interconnection, adaptive traffic signal coordination, fiber optic cable and video surveillance installation."

Click here to view the project list.

For those projects authorized for construction, work is expected to begin within 18 months.

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