It is the duty of the Department of Transportation to operate a ferry route or routes between the mainland and the towns of North Haven, Vinalhaven, Islesboro, Matinicus Isle and Swan’s Island for the purpose of transporting vehicles, freight and passengers to and from these towns, and the department may operate the ferry route or routes to and from Frenchboro. Ferry service to Matinicus Isle must be at least 12 times per year and may be up to 36 times per year and may be provided by state-owned or privately contracted vessels. These ferry routes are designated as the “Maine State Ferry Service.” During periods of facility repair or maintenance or during periods of extraordinary demand, the department may carry out its responsibilities by utilizing privately contracted vessels to provide additional or substitute service to islands served by the Maine State Ferry Service as long as the use of privately contracted vessels is in accordance with an agreement between the department and the State’s collective bargaining agent as defined in Title 26, section 979?A, subsection 1. [PL 1999, c. 20, §1 (AMD).]