The grade of all streets, sidewalks and alleys shall be established
by the Common Council and recorded by the Clerk-Treasurer in his office.
No street or alley shall be worked or sidewalk constructed until the
grade thereof is established.
No person shall alter the grade of any street, alley, sidewalk
or public ground, or any part thereof, in the City unless authorized
or instructed to do so by the Common Council or the Director of Public
Works. All such alterations of grade shall be recorded in the office
of the Clerk-Treasurer.