The selectmen of the town or the street commissioner of the city in which such bridge is situate, may grant a written permit to carry a load in excess of such posted load limit on such conditions and under such regulations as such selectmen or street commissioner believe will permit a safe travel of such excessive load without damage to such bridge.
RSA 234:40
1945, 188:1, part 21:17. RSA 251:17. 1981, 87:1, eff. April 20, 1981.