All street grades shall be designed as follows:
(A) Major and collector streets: Limited to a maximum grade of 10%. Sustained grades shall be limited to 7%;
(B) Minor streets: Limited to a maximum grade of 12%. Sustained grades shall be limited to 9%;
(C) Cul-de-sacs with a negative grade progressing toward the turnaround shall be limited to a maximum grade of 6%. The cul-de-sac shall terminate with a grade not to exceed 3% for the last 100 feet of traveled surface. The cul-de-sac shall be limited to a maximum length of 650 feet and have adequate easement for drainage;
(D) Street intersections shall have a vertical alignment such that the grade shall not exceed 3% for a minimum distance of 50 feet each way from the centerline of the intersection;
(E) Maximum grades: Approved only when accompanied by changes to a lesser grade, and where the length of that portion of that road at maximum grade is less than 600 feet;
(G) All changes in vertical alignment: Made by vertical curves with a minimum length of 200 feet for minor streets and 300 feet for major streets (see § 153.115); and
(H) Streets in mountainous terrain shall be designed at less than maximum allowable slope in order that they can be safely negotiated, and that snow can be removed during winter.
(Ord. 2024-5-2, passed 5-13-2024) Penalty, see § 153.999