(A) In order to establish that an adequate drainage outlet(s) exists for a proposed subdivision seeking a primary plat approval from the County Plan Commission, or for certain commercial developments as determined by the County Surveyor, a developer must first apply for a preliminary drainage approval from the county. As part of the noted primary drainage approval application, a developer shall submit conceptual drainage plans for review by the county prior to the Drainage Board meeting and Plan Commission hearing. Note that any preliminary drainage approval by the county, as a result of such a review, is based on preliminary data and shall not be construed as a final drainage approval, or considered binding on either party. Once a development receives primary drainage approval from the County Drainage Board, all subsequent processing for the necessary stormwater approvals will remain with the County Drainage Board, including all individual sections or phases of the development.
(B) The following is a general listing of minimum data requirements for the review of conceptual drainage plans, all of which must be on a CD, or other acceptable media acceptable to the county:
(1) Letter of intent for obtaining any needed consents, off-site easements, or right-of- way;
(2) Project narrative and supporting documents, including:
(a) Description of the nature and purpose of the project;
(b) General description of the existing and proposed drainage systems in narrative form;
(c) General description of regulated drains, farm drains, inlets, and outfalls in narrative form, if any of record;
(d) General description of all existing storm, sanitary, combined sewer, and septic tank systems and outfalls in narrative form;
(e) Two copies of drainage calculations showing existing and proposed discharges for various storm events;
(f) Vicinity map depicting the project site location in relation to recognizable local landmarks, towns, and major roads, such as a USGS topographic quadrangle map, or county or municipal road map;
(g) A map showing the location, name, and normal water level of all wetlands, lakes, ponds, and watercourses on, or adjacent to, the project site;
(h) A map showing 100- year floodplains, floodway fringes, and floodways. Please note if none exists;
(i) A map showing watershed boundaries with USGS contours or best information possible; and
(j) A map showing existing watercourse or regulated drains.
(3) Conceptual plans, including three complete sets of conceptual plans showing general project layout, including existing and proposed drainage systems and proposed outlets.
(4) One plan set should be 11 inches by 17 inches in size, and two plan sets should be 24 inches by 36 inches in size.
(C) All the required information shall be submitted in electronic format compatible with the county GIS. All mapping and survey data must be in state plane coordinates with the following metadata requirements:
(1) State west;
(2) U.S. Survey feet;
(3) GNS 80 ellipsoid;
(4) NAVD 88;
(5) GEOID 09;
(6) NAD 83;
(7) CORS 96; and
(8) EPOCH 2002 or later.
(Ord. 2017-03, passed 1-24-2017)