The objectives of chapters 1 to 19 are to establish a Department of Transportation; to provide for an interlocking system of state and state aid highways; to furnish state aid for county and town highways and bridges; to provide for the continuous maintenance of all highways and bridges to the improvement of which the State has contributed or shall hereafter contribute unless otherwise provided by law; to provide for the equitable distribution of the proceeds of state bonds issued for the construction of highways and bridges; and to cooperate with the Federal Government in the construction of highways and bridges.   [PL 1981, c. 492, Pt. C, §1 (AMD).]