Federal regulators have approved the controversial Sabal Trail natural gas pipeline project, which will cut through conservation areas, under rivers and near springs in north central Florida. The Federal Energy Regulatory Commission (FERC) has issued a certificate of public convenience and necessity for the $3.2 billion, 516-mile, three-foot-wide pipeline that will carry up to 1 billion cubic feet of natural gas a day from Alabama through south Georgia and a dozen Florida counties, including Alachua, Gilchrist, Suwannee, Levy and Marion, to a connector pipeline in Osceola County. The pipeline will supply natural gas for a Florida Power & Light electric generation and a Duke Energy plant in Citrus County. The pipeline is a joint venture between FPL parent company NextEra, Duke and Spectra Energy, the Houston-based company that will build and operate it. Spectra Energy said construction was expected to start in May or June, with the pipeline in operation by May 1, 2017.