Miami Dade College is pushing for a half-cent sales tax increase to fund construction and expanded programming. Under the plan, county voters must approve the tax, which would last at least five years and generate an estimated $160 million annually. But state lawmakers, who must give the go-ahead for a referendum, have shown little interest, arguing that Miami-Dade already has a half-cent tax for public health and a half-cent tax for transportation on top of the state's 6% sales tax. Some parts of the county also pay tourist taxes.