It is illegal to excavate any city street.

ARTICLE VIII
STREETS, SIDEWALKS AND PUBLIC WAYS

SECTION 5. No person, except employees in the Department of Public Works in the lawful performance of their duties, shall make or cause to be made any excavation in a public street or way, for any purpose whatever, without first obtaining written permission from the Selectmen. When an excavation is made in a public street or way for any purpose, or a private way furnishing access to any fire apparatus, the person or persons by whom or for whom such excavation is made, shall cause a rail or other sufficient fence to be placed so as to enclose such excavation and the dirt, gravel or other material thrown therefrom, and such fence shall be maintained the whole time that such excavation continues. Such fence, excavation and material excavated shall be lighted by a lantern, lanterns or other proper and sufficient light, from the beginning of twilight throughout the whole of every night during the entire time that such excavation or obstruction exists.