Promoting its campaign to bring higher wages to Los Angeles workers, the county labor federation released a study Tuesday that says 810,864 Angelenos live with "poverty" wages of less than $15 an hour.

Maria Elena Durazo, chief of the Los Angeles County Federation of Labor, said that a raise to $15 would not only help low-wage workers but also provide a massive economic stimulus for the entire regional economy.

As it released the report from the Economic Roundtable at a news conference near MacArthur Park, the labor group also unveiled billboards, styled after green "city limits" signs, that read: "Los Angeles, City Limited, Poverty Wage Pop. 810,864." The signs appear at seven locations near downtown, on the Westside and near Los Angeles International Airport.

The Economic Roundtable study estimates that 46% of the city's wage and salary workers make less than $15 an hour and says that low-wage workers whose pay is boosted to that level are much more likely to pump the money back into the local economy than those who make more.

The study from the liberal-leaning organization suggests that a $15-an-hour minimum wage would increase payrolls in Los Angeles by about 10%, or $7.6 billion annually. Increased spending by those workers would stimulate the economy enough to create 64,700 jobs in Los Angeles County, the report says.

The report comes as the county labor federation and the hotel and restaurant workers union, Unite Here Local 11, have launched a campaign to require a $15.37 hourly wage for workers in Los Angeles hotels with at least 100 rooms. Los Angeles City Council members are expected to introduce a minimum-wage ordinance early this year.

Durazo rejected the notion that the billboard campaign would hurt the reputation of Los Angeles.

"A billboard is not going to bring us down," she said. "What's bringing us down is workers who have to work two or three jobs, who can't be with their kids [and] give them the attention that they need," Durazo said. "What's bringing the city down is we don't have enough revenue for the services that all of us depend on. What's bringing us down is more and more people are being left out there homeless.... Let's be aware of the problem and do something about it."

Hotel owners and business interests have suggested that the higher minimum wage would lead to worker layoffs or higher prices for consumers. They have also argued that it would discourage developers from building new hotels, particularly in emerging markets such as downtown Los Angeles.

The Economic Roundtable paper said the wage increase could be accomplished, instead, by reducing the wages of higher earners, cutting worker turnover and increasing prices slightly.

It said many economists found no harm from such minimum-wage increases but also recommended that wages be increased incrementally, "so as not to cause economic dislocation."

Details of the proposal that will be brought to the City Council for hotel workers have not been spelled out. But the measure's supporters intend to press hard for an immediate increase to $15.37 (matching the minimum wage previously mandated for workers at LAX), not a gradual phase-in of the higher wage.

The state minimum wage of $8 an hour is scheduled to increase to $9 in July and $10 in 2016. The annual income of a full-time worker earning $15 an hour today would be roughly twice the federal poverty threshold, depending on family size, according to the Economic Roundtable. But the higher wage is the minimum to create a standard of "well being" in high-cost cities, the organization's report said.

james.rainey@latimes.com

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