(A) General.
(3) Any encroachment in the regulatory floodway is prohibited unless the data submitted for division (A)(2) above demonstrates that the encroachment will cause no increase in flood elevations in flood events up to the base flood at any location or removes the encroached area from the regulatory floodway as provided in § 15.3.005(E).
(B) Structures. Structures accessory to permanent open space uses, including utility and sanitary facilities, or functionally dependent on a waterfront location may be allowed by permit if the structures comply with the following criteria:
(1) Not designed for human habitation, does not have a high flood damage potential and is constructed to minimize flood damage; and
(2) Shall either have the lowest floor elevated to or above the flood protection elevation or shall meet all the following standards:
(a) Have the lowest floor elevated to or above the regional flood elevation and be dry floodproofed so that the structure is watertight with walls substantially impermeable to the passage of water and completely dry to the flood protection elevation without human intervention during flooding; and
(b) Have structural components capable of meeting all provisions of division (B)(7) below of this section; and
(c) Be certified by a registered professional engineer or architect, through the use of a Federal Emergency Management Agency Floodproofing Certificate, that the design and methods of construction are in accordance with division (B)(7) below.
(3) Must be anchored to resist flotation, collapse, and lateral movement.
(4) Mechanical and utility equipment must be elevated to or above the flood protection elevation; and
(5) Must not obstruct flow of flood waters or cause any increase in flood levels during the occurrence of the regional flood.
(6) For a structure designed to allow the automatic entry of floodwaters below the Regional Flood Elevation, the applicant shall submit a plan that meets divisions (B)(1) through (B)(5) above and meets or exceeds the following standards:
(a) The lowest floor must be elevated to or above the regional flood elevation; and
(b) A minimum of 2 openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding; and
(c) The bottom of all openings shall be no higher than one foot above the lowest adjacent grade; openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters, otherwise must remain open.
(d) The use must be limited to parking, building access or limited storage.
(7) Certification. Whenever floodproofing measures are required, a registered professional engineer or architect shall certify that the following floodproofing measures will be utilized, where appropriate, and are adequate to withstand the flood depths, pressures, velocities, impact and uplift forces
and other factors associated with the regional flood:
(a) Reinforcement of floors and walls to resist rupture, collapse, or lateral movement caused by water pressures or debris buildup; and
(b) Construction of wells, water supply systems and waste treatment systems so as to prevent the entrance of flood waters in such systems and must be in accordance with provisions in § 15.3.024(D) and (E); and
(c) Subsurface drainage systems to relieve external pressures on foundation walls and basement floors; and
(d) Cutoff valves on sewer lines or the elimination of gravity flow basement drains; and
(e) Placement of utilities to or above the flood protection elevation.
(C) Public utilities, streets and bridges. Public utilities, streets and bridges may be allowed by permit, if:
(1) Adequate floodproofing measures are provided to the flood protection elevation; and
(2) Construction meets the development standards of § 15.3.011.
(D) Fills or deposition of materials. Fills or deposition of materials may be allowed by permit, if:
(1) The requirements of § 15.3.011 are met; and
(2) No material is deposited in navigable waters unless a permit is issued by the Department pursuant to Wisconsin Statutes Ch. 30, and a permit pursuant to § 404 of the Federal Water Pollution Control Act, Amendments of 1972, 33 U.S.C. 1344 has been issued, if applicable, and all other requirements have been met; and
(3) The fill or other materials will be protected against erosion by riprap, vegetative cover, sheet piling or bulkheading; and
(4) The fill is not classified as a solid or hazardous material.
(Ord. 904, passed 5-2-06; Am. Ord. 1095, passed 1-16-24)