A proposal to put a 2 percent tax on all alcohol sales in Boston is slated for a City Council hearing on Thursday.

The hearing was scheduled for 11 a.m. at Boston City Hall. The idea was proposed by City Council President Bill Linehan and Councilor Frank Baker. It would raise about $20 million to use for substance abuse and prevention programs.

Liquor store owners have said the tax could drive away customers and hurt business. One liquor store owner predicted he'd lose one-third of his business to liquor stores outside the city if the tax is implemented.