(A) Each applicant shall submit the following information, to ensure that the provisions of this chapter are met. The submittal shall include sufficient information to evaluate the environmental characteristics of the property, the potential adverse impacts and benefits of the development on water resources both on-site and off-site, and the effectiveness of the proposed drainage plan in managing storm water runoff, and meet the provisions of § 153.002. The applicant shall certify on the drawings that all clearing, grading, drainage and construction shall be accomplished in strict conformance with the drainage plan.
(B) The following information shall be submitted for both existing and proposed property conditions for all new development or redevelopment.
(1) Drainage plan requirements. A topographic survey of the property at two-foot contours unless otherwise specified or approved by the county. If the mapping is compiled using a digital format and the global positioning system (GPS), the applicant will provide both paper and digital copies including GPS points.
(2) Mapping and descriptions. An existing drainage and proposed drainage plan, for the property and 100 feet surrounding the property at a scale of not more than 100 feet to one inch and including the following:
(a) Property boundary, dimensions and approximate acreage;
(b) Building setback lines;
(c) All existing and proposed structures and sizes;
(d) Area in square feet of existing and proposed impervious surface;
(e) All existing or proposed easements;
(f) All existing, abandoned or proposed water or monitoring well head locations;
(g) All sanitary or combined sewer lines and septic systems;
(h) The banks and centerline of streams and channels;
(i) Shoreline of lakes, ponds and detention basins with normal water level elevation;
(j) Known farm drains and tiles;
(k) Soils classifications;
(l) Location, size and slope of storm water conduits and drainage swales;
(m) Depressional storage areas;
(n) Detention facilities;
(o) Roads, streets and associated storm water inlets including finished grades;
(p) Base flood elevation, flood fringe and regulatory floodway;
(q) Basis of design for the final drainage network components;
(r) A statement giving any applicable engineering assumptions and calculations;
(s) A vicinity map showing the relationship of the site to its general surroundings at a scale of not less than 2,000 feet to one inch (1:24,000);
(t) Title, scale, north arrow, legend, seal of licensed professional engineer, date and name of person preparing plans;
(u) Cross-section data for open channel flow paths and designated overland flow paths;
(v) Direction of storm flows;
(w) Flow rates and velocities at critical points in the drainage system (may be included in the supporting documentation);
(x) A statement by the design engineer of the drainage system’s provision for handling events greater than the 100-year, 24-hour runoff (may be included in the supporting documentation); and
(y) A statement of certification of all drainage plans, calculations and supporting data by a licensed professional engineer.
(3) Environmental features. A depiction of environmental features of the property and immediate vicinity including the following:
(a) The limits of designated regulatory and non-regulatory wetland areas;
(b) The location and limits of known sinkholes (karst areas);
(c) Any known designated natural areas, prime farmland; and
(d) Any known proposed environmental mitigation features.
(Ord. passed 9-8-2009)