This chapter is designed to meet the requirements of the Code of Iowa for the establishment of street grades. As used herein, “grade” means the longitudinal reference lines, as established by ordinance of the Council, which designate the elevation at which a street or sidewalk is to be built.

   The grades of all streets, alleys, and sidewalks, which have been heretofore established by ordinance, are hereby confirmed, ratified, and established as official grades.

   The Clerk shall maintain a record of all established grades and furnish information concerning such grades upon request.