Section 131-G. Regulation of toll rates

Such boards shall have power by a
  vote  of  two-thirds  of  all  the  members  elected  to  authorize   an
  alteration, reduction or change of the rates of toll charged or received
  by  any  turnpike,  plank or gravel road, or other toll road within such
  county, or by any bridge company or ferry within  such  county,  or,  if
  within  more  than one county, then by joint action with the supervisors
  of such counties, provided such alteration shall be  asked  for  by  the
  directors, trustees or owners of such road, bridge or ferry; but that no
  increase  of  toll shall be so authorized unless notice of such proposed
  increase shall have been published once each week for  three  successive
  weeks  in  a  newspaper having general circulation in each town in which
  such road or bridge is located or  in  which  such  ferry  is  operated,
  commencing at least thirty days prior to the date of such authorization;
  and  any  alteration  in  rates  of  toll  authorized  by  any  board of
  supervisors may be changed or modified by any subsequent board, on their
  own motion, by a like vote of two-thirds of all the members  elected  to
  such  board;  but  nothing  herein contained shall affect or abridge the
  powers of any city.