Section 91. Powers and duties of commissioner

The commissioner, subject to
  the provisions  of  law  and  ordinances  of  the  common  council,  has
  cognizance,  direction  and  control  of  the construction, maintenance,
  alteration, repair,  care,  cleaning,  paving,  flagging,  lighting  and
  improving  of  the streets, highways, sidewalks and public places of the
  city; of the construction, alteration and repair of all  city  buildings
  and of all docks and bridges belonging to the city; of all public sewers
  and  drains  in  the  city; of the construction, maintenance, extension,
  repair and care of the city waterworks; of the care, superintendence and
  management and improvement of all parks and grounds,  public  baths  and
  recreation  piers belonging to the city. Except as otherwise provided by
  law, the commissioner  shall  have  supervision  of,  control  over  and
  jurisdiction  and authority to make all ordinary repairs or improvements
  upon the streets, parks, sidewalks, crosswalks, gutters, vaults, drains,
  culverts, bridges and public ways and places of the city, including  the
  cleaning,  sprinkling,  laying of dust with substances other than water,
  watering and flushing of the same, and  may  employ  such  laborers  and
  teams  and incur such expenditures as may be necessary within the limits
  of the appropriations made therefor. It shall be his duty to inspect the
  same with sufficient frequency to ascertain their  condition  and  cause
  the  same  to  be  kept free from obstructions and in good condition and
  repair and reasonably safe for public use. The commissioner  shall  also
  have  general  supervision  and  control of all work performed under any
  contract of the city for local or other  improvements  to  be  performed
  within  or  upon  any  of the public streets, parks, ways and places, or
  with reference to the public works and ways within the  jurisdiction  of
  his  department, including the lighting, sprinkling, laying of dust with
  substances other than water, watering or  flushing  of  the  streets  or
  public  places,  and  shall  cause  the  same  to  be  performed in full
  compliance with the provisions  of  any  contract  therefor.  Except  as
  otherwise  provided  by  law  or  ordinance  of  the common council, the
  commissioner of public works has, over the  streets  and  public  places
  within the city, all the jurisdiction and is charged with all the duties
  of commissioners of highways within the towns of the state.