Pedestrians walk by an entrance to the UC Berkeley campus. (Photo by Justin Sullivan/Getty Images)

BERKELEY (CBS SF) – Administrative workers at the University of California will go on strike at all 10 UC campuses, five medical centers and the Lawrence Berkeley National Lab next month, a union spokesman said Thursday.

The system-wide Teamsters Local 2010 strike by administrative workers, planned for Jan. 10, is in solidarity with a corresponding five-day strike at the University of California at Los Angeles, union spokesman Christian Castro said.

Castro said that Teamsters would give the university more than the legally required 10-day notice to transfer patients and ensure that students, staff, faculty and the public are protected from harm.

The UCLA strike by skilled trades workers including electricians, elevator mechanics, plumbers and facilities workers will last from Jan. 6 to Jan. 10.

Skilled trades workers have not had a raise in four years at UCLA, and in two years at UCSD, Castro said.

The university “unlawfully refuses to bargain” for retroactive pay raises after admitting the money was budgeted for those unpaid wage increases, Castro said.

Teamsters workers have seen their wages drop 24 percent over the last two decades, Castro said, adding that 92 percent can’t afford basic necessities.

In October, UC spokeswoman Dianne Klein said that Teamsters workers make $43,600 on average and enjoy a “heavily subsidized” healthcare package, overtime pay and a pension program.

A survey of 2,890 of these union workers, released by the Urban and Environmental Policy Institute at Occidental College on Oct. 17, found that 70 percent were food-insecure.

UC officials did not immediately return a request for comment.

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