The Los Angeles County Board of Supervisors voted Tuesday to incrementally raise the minimum wage in unincorporated areas over the next five years, reaching $15 an hour by 2020.

Supervisor Hilda Solis, initially hesitant about the possible impact on small businesses, joined Sheila Kuehl and Mark Ridley-Thomas in backing the ordinance. Supervisors Michael Antonovich and Don Knabe dissented, with Knabe voting in favor of the hike for county employees only.

Kuehl's county wage hike would — like the increase recently approved by the city of Los Angeles — include a series of increases over five years, beginning July 1, 2016, and reaching $15 an hour by 2020. The wage would go to $10.50 in July 2016, $12 in July 2017, $13.25 in July 2018 and $14.25 in July 2019. Like the city increase, Kuehl's proposal would delay the increase by one year for businesses with fewer than 26 employees.

"The more you make, the more you spend," Keuhl told NBC4 Tuesday.

After 2020, the wage would be adjusted annually based on the cost of living.

Kuehl said earlier she was making the proposal because "many county residents, despite working full time, earn too little in wages to cover even the bare necessities, such as safe housing, healthy food, adequate clothing and basic medical care."

Dr. Kevin McNamee, a chiropractor who owns a small business in the city, said he "can't afford to do business in LA anymore.

"By increasing the minimum wage, you have shifted money from the owner who works very hard and more than 40 hours a week to keep the business going, and you shift the money from the employer over to the employee," McNamee said. "So essentially you’re penalizing the employer for running the business."

Outside the meeting, those who make the current minimum wage of $9 an hour said they can't live on their pay.

"With the minimum for $9, it's too hard to pay rent, bills," fast food worker Mary Farfan said.

The board discussed the proposal last month, but postponed a vote due to concerns over a Los Angeles County Economic Development Corporation report on the issue.

Supervisor Mike Antonovich said he was disappointed the report did not outline the possible effects of a wage increase on nonprofits. He also said he wanted information about the effects of a wage increase on businesses that will be operating across the street from others without the same salary requirements.

He also suggested that some large businesses — such as Magic Mountain theme park — could be annexed into other cities to avoid paying the higher wages, costing the county tax dollars.

On Monday, Kuehl lashed out at a new study on the issue, performed by the Employment Policies Institute, saying it would be "laughable if $55,000 of taxpayer money hadn't been wasted on it."

"Sadly enough, that's more than three full-time minimum-wage workers earn in a year," Kuehl said.