Effective January 1, 2009, the Department's regulation for vertical clearance over roadways is 18 feet, minimum. To meet the regulation, the clearance shall be calculated by the Utility Company to cover the anticipated sag, loading characteristics, and type of wire at the time the initial facility is installed. Please note: the previous standard that the Department required (15.5. feet) was based on the National Electric Safety Code. This current regulation is not meant to be retroactive; thus, as Utilities affect aerial crossings, from the effective date and in the future, the 18-foot minimum clearance will be obtained.