Facing new challenges in an election year, U.S. union tradeswomen attending a second annual conference in May in Sacramento reviewed anti-union measures on ballots across the U.S. and vowed to unite to slow attrition.

The conference, co-sponsored by the AFL-CIO's Building and Construction Trades Dept. and the California State Building and Construction Trades Council (SBCTC), attracted women craft workers from 26 states and from abroad. With 100 fewer attendees than last year, 520 came to the 11th annual meeting for state tradeswomen.

SBCTC spokeswoman Debra Chaplan, also a member of Teamsters' union Local 853, said women now make up just 2% of the U.S. construction workforce, down from a peak of 8% in 2008. Melina Harris, president of Sisters in the Building Trades, a Renton, Wash., activist group, says many tradeswomen are working so infrequently that they are leaving the industry to find more reliable jobs to support their families. "Retention is a big problem," she says.

Sessions stressing political activism—with names such as "We Are the 99%" and "The Political Fight in the States: Stopping the War on Workers"—were popular. Bryan Blum, political director at the California Labor Federation, said a November state ballot measure, called the "Stop Special Interest Money Now Act," is really "an anti-union dues measure and does not affect corporate Super PACs and billionaires."

Warren Whitlock, associate administrator of the Federal Highway Administration's civil rights office, called for more "online metrics" of how states are meeting compliance goals. Dept. of Labor's Jane Oates added, "You need to get unions and the construction sector strengthened and back on their feet before you turn to women and apprentices." Whitlock called on attendees to "make noise. You've got to let people know what you want."