§ 30-282. Drainage plan requirements; all categories of development.

(a)

Drainage map. The project engineer shall include in the construction plans a master drainage map showing all existing and proposed features. The map is to be prepared on a twenty-four-inch by thirty-six-inch sheet on a scale not to exceed one (1) inch equals two hundred (200) feet. The following shall be included on the drainage map:

(1)

Drainage bounds, including all off-site areas draining to the proposed site.

(2)

Sufficient topographical information with elevations to verify the location of all ridges, streams, etc., (one-foot contour intervals).

(3)

High water data on existing structures upstream and downstream from the site.

(4)

Notes indicating sources of highway data.

(5)

Notes pertaining to existing standing water, area of heavy seepage, or springs.

(6)

Existing drainage features (ditches, roadways, pond, etc.). Existing drainage features are to be shown a minimum of one thousand (1,000) feet downstream of the proposed development, unless the ultimate outfall system is a lesser distance.

(7)

Drainage features, including location of inlets, swales, ponding area, etc.

(8)

Delineation of drainage sub-areas.

(9)

General type of soils (obtain from soil survey of the county).

(10)

Flood hazard classification.

(11)

Description of current ground cover and/or land use.

(b)

Subsoil investigation. A subsoil report shall be prepared by a geotechnical engineer experienced in the preparation of this type of report. The contents of the subsoil report will be in accordance with section 30-280(d).

(c)

Stormwater calculations. Stormwater calculations for retention/detention areas, including design high water elevations for the twenty-five-year and one-hundred-year storm events shall include the following:

(1)

Cross sections of retention/detention facilities.

(2)

Typical swale, ditch or canal sections.

(3)

Drainage, rights-of-way.

(4)

Typical fencing detail.

(5)

Note on the design plans that an erosion control plan will be submitted to the county engineer for approval prior to the preconstruction conference.

(Code 1965, § 32-66(g); Ord. No. 86-20, § 1(g), 8-25-86)