A separate grading plan shall be submitted that shall consist of the following data and information:
(a) The plan shall be prepared at a scale of 1" = 50' or at a scale approved by the City Engineer;
(b) The plan shall indicate ground elevations with existing and proposed contours shown at intervals of not more than five feet where the slope is greater than ten percent and not more than two feet intervals where slope is ten percent or less;
(c) Proposed elevations shall be shown at all lot corners, change in lot grades, inlets, manholes and other points critical to the drainage of the area;
(d) Directional arrows or flow shall be shown to adequately define surface flow directions;
(e) Proposed sanitary and storm sewer top of casting elevations shall be shown;
(f) Routing of the 100-year major storm shall be shown;
(g) First floor elevations of all existing and proposed buildings shall be designated to the nearest tenth of a foot;
(h) The minimum building elevation adjacent to the 100-year routing path shall be set a minimum of one foot above 100-year flood elevation. No basement entrances, windows or basement level garages shall be permitted below the 100-year routing path elevation;
(i) Swales necessary to carry surface water must have a minimum gradient of one percent;
(j) The maximum distance for overland flow shall be 300 feet before entering a surface yard inlet or 425 feet before entering a curb inlet. The maximum distance for curb inlets shall not exceed 400 feet;
(k) Lots shall be graded so that water drains away from each building at a minimum grade of two percent for a distance of ten feet;
(l) The area encompassed within the Master Grading Plan shall be compatible with any area-wide drainage plan or adjacent areas;
(m) The plot plan for each building permit shall include the same grading, draining and elevation information as the Master Grading Plan.
(Ord. 5049. Passed 7-7-03.)