The foregoing provisions shall not apply to railroads when making necessary repairs or improvements within their rights-of-way at points where the same are crossed by a highway; but no such repairs or improvements, if they involve excavating or disturbing the surface of any highway, shall be made without written permission from the department of transportation.
RSA 236:12
1917, 96:4. PL 91 :4. RL 107:6. 1945, 188:1, part 19:11. RSA 249:16. 1981, 87:1. 1990, 39:2, eff. May 22, 1990.