Whenever a highway located after the first day of January, 1906 crosses any river which divides towns, the expense of constructing, maintaining and repairing any bridge across such river shall be borne by such towns in proportion to their last state valuation prior to such location. This section shall not apply to bridges built or rebuilt under sections 353 and 355.   [PL 1989, c. 502, Pt. A, §90 (AMD).]