The grant of every franchise or privilege shall be subject to the right of the city, whether reserved in such grant or not, to make all regulations which shall be necessary to secure in the most ample manner the safety, welfare and accommodation of the public, including among other things, the right to pass and enforce ordinances to protect the public from danger or inconvenience in the operation of any work or business authorized by the grant of the franchise and the right to make and enforce all such regulations as shall be reasonably necessary to secure adequate, sufficient and proper service and accommodations for the people and insure their comfort and convenience.