(a) Flatland Subdivisions. The following requirements are applicable to all flatland subdivisions within the jurisdiction of the City Development Department:
(1) The grades of any street or alley shall not be less than five-tenths percent.
(2) Arterial, collector or secondary highways as designated by the Thoroughfare Plan shall be limited to a maximum grade of five percent.
(3) Local, minor and dead-end streets shall be limited to a maximum grade of ten percent.
(4) Alleys shall be limited to a maximum grade of ten percent where they are primarily for residential service, but shall be limited to a maximum of eight percent when used to provide service to commercial property.
(5) Pedestrian ways or crosswalks shall be limited to a maximum grade of twenty percent unless steps of an acceptable design are to be constructed.
(6) All changes in street grade of one percent or more shall be connected by vertical curves. The length of the vertical curve will be determined on the basis of providing stopping sight distances for each road classification where design speed for arterial, collector and secondary streets is forty miles per hour, local streets is twenty-five miles per hour, and minor streets, dead-end streets and alleys is twenty miles per hour. In no case shall the length of the required vertical curve be less than fifteen times the algebraic difference in rate of grades for arterials, collectors and secondary streets or one-half of this minimum for all other streets.
(7) The radii of curvature on the center line of the street shall not be less than that required to produce stopping sight distance as defined in paragraph (6) hereof. In no case, however, shall the radii of curvature for arterials, collectors and secondary streets be less than 300 feet or for local streets, minor streets, service drives and alleys be less than fifty feet.
(b) Hillside Subdivisions. The following requirements are applicable to all hillside subdivisions within the jurisdiction of the City Development Department:
(1) The following requirements of subsection (a) hereof for flatland subdivisions are applicable for hillside subdivisions: 1309.05(a)(1), (2) and (5).
(2) Local streets shall be limited to a maximum grade of twelve percent and minor streets and dead-end streets to a maximum grade of fifteen percent.
(3) Service drives and alleys where required or permitted shall be limited to a maximum grade of twelve percent where they are primarily for residential services, but shall be limited to a maximum of ten percent when used to provide service to commercial property.
(4) All changes in street grade of one percent or more shall be connected by vertical curves. The length of the vertical curve will be determined on the basis of providing stopping sight distances for each road classification where design speed for arterial, collector and secondary streets is forty miles per hour, local streets is twenty miles per hour, and minor streets, dead-end streets and alleys is fifteen miles per hour. In no case shall the length of the required vertical curve be less than fifteen times the algebraic difference in rate of grades for arterials, collectors and secondary streets or one-half of this minimum for all other streets.
(5) The radii of curvature on the center line of the street shall not be less than that required to produce stopping sight distance as defined in paragraph (4) hereof. In no case, however, shall the radii of curvature for arterials, collectors and secondary streets be less than 300 feet or for local streets, minor streets, service drives and alleys be less than fifty feet. (Ord. A- 1090. Passed 4-4-67; Ord. A-3169. Passed 3-23-76.)