(a) All proposed grades shall be the centerline grades of the respective streets and shall be indicated in complete detail in profiles and referenced to the stationing shown on the plan.
(b) The maximum grades shall not exceed six percent (6%) for main and secondary thoroughfares, or twelve percent (12%) for minor local service streets. The minimum grade of all streets shall be one percent (1%). Grades across intersections shall not be in excess of four percent (4%) except at the discretion of the City Engineer.
(c) In street cul-de-sacs the maximum profile grade shall not exceed four percent (4%) and the minimum profile grade shall not be less then one and two-tenths percent (1.2%).
(d) All changes in grade shall be connected by vertical curves of minimum length equal to fifteen (15) times the algebraic difference in rate of grade for thoroughfares, and one-half (1/2) this minimum length for minor or local service streets. The Point of Vertical Curvature (PVC) and the Point of Vertical Tangency (PVT) of all vertical curves shall be stationed and elevations shall be shown at least every twenty-five feet (25') within the limits of vertical curves.
(e) The profile grade for streets shall be maintained a minimum of one-foot (1') above the base flood elevation for areas included in Section 3.2 of the Flood Damage Prevention Regulations of the Hamilton County Department of Public Works.
(f) Wherever a proposed street is an extension of a previously constructed street which is not part of the proposed subdivision, profile grades shall be developed for at least the last two hundred feet (200') of the existing street which will abut the new extension. This is to insure a smooth transition of pavement, gutters and sidewalks. Particular attention shall be given to any pavement overlays that would affect the proposed improvement. Details of connections shall be shown on the Commissions plans.