Town of Bethany Beach, DE Article V Requirements in Special Flood Hazard Areas Other Than Coastal High-Hazard Areas

§ 453-25 General requirements.

In addition to the general requirements of Article IV, the requirements of this article apply to all development proposed in special flood hazard areas other than coastal high-hazard areas. These areas include Zones AE and AO.

§ 453-26 Residential structures and residential portions of mixed-use structures.

A. Elevation requirements.

(1) The lowest floor (including basement) shall be elevated to or above the base flood elevation plus 18 inches.

(2) In areas of shallow flooding (Zone AO), the lowest floor (including basement) shall be elevated at least as high above the highest adjacent grade as the depth number specified in feet on the Flood Insurance Rate Map plus 18 inches, or at least two feet plus 18 inches if a depth number is not specified; adequate drainage paths shall be provided to guide floodwaters around and away from the structure.

(3) Enclosures below the lowest floor shall meet the requirements of § 453-26B.

B. Enclosures below the lowest floor.

(1) Enclosures below the lowest floor shall be used solely for parking of vehicles, building access, crawlspaces, or limited storage.

(2) Enclosures below the lowest floor shall be constructed using flood-damage-resistant materials. See FEMA Technical Bulletin No. 2, Flood Damage-Resistant Materials Requirements.

(3) Enclosures below the lowest floor (including crawlspaces) shall be provided with flood openings which shall meet the following criteria (see FEMA Technical Bulletin No. 1, Openings in Foundation Walls and Walls of Enclosures):

(a) There shall be a minimum of two openings on different sides of each enclosed area; if a building has more than one enclosed area below the base flood elevation, each area shall have openings on exterior walls.

(b) The total net area of all openings shall be at least one square inch for each square foot of enclosed area, or the openings shall be designed and certified by a registered engineer or architect to provide for equalization of hydrostatic flood forces on exterior walls by allowing for the automatic entry and exit of floodwaters.

(c) The bottom of each opening shall be one foot or less above the adjacent ground level.

(d) Any louvers, screens or other opening covers shall allow the automatic flow of floodwaters into and out of the enclosed area.

(e) Where installed in doors and windows, openings that meet the requirements of § 453-26B(3)(a) through (d) are acceptable; however, doors and windows without installed openings do not meet the requirements of this section.

(4) Crawlspaces shall have the finished interior ground level equal to or higher than the outside finished ground level on at least one entire side of the foundation wall.

C. Manufactured homes. In accordance with § 425-20 of the Code of Ordinances, the type of manufactured homes that are defined as "mobile homes" in the Town's Zoning Code (§ 425-2, Definitions) are not permitted in the Town of Bethany Beach.

§ 453-27 Nonresidential structures and nonresidential portions of mixed-use structures.

A. Elevation requirements.

(1) The lowest floor (including basement) shall be elevated to or above the base flood elevation plus 18 inches or the structure shall be dry floodproofed in accordance with § 453-27B.

(2) In areas of shallow flooding (Zone AO), if not dry floodproofed, the lowest floor (including basement) shall be elevated at least as high above the highest adjacent grade as the depth number specified in feet on the Flood Insurance Rate Map plus 18 inches, or at least two feet plus 18 inches if a depth number is not specified; adequate drainage paths shall be provided to guide floodwaters around and away from the structure.

(3) Enclosures below the lowest floor, if not dry floodproofed, shall meet the requirements of § 453-26B.

B. Dry floodproofing requirements. Dry floodproofed structures, together with attendant utility and sanitary facilities, shall:

(1) Be designed to be dry floodproofed such that the structure is watertight with walls and floors substantially impermeable to the passage of water to the level of the base flood elevation plus 18 inches. In areas of shallow flooding (Zone AO), the structure shall be dry floodproofed at least as high above the highest adjacent grade as the depth number specified in feet on the Flood Insurance Rate Map plus 18 inches, or at least two feet plus 18 inches if a depth number is not specified.

(2) Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy.

(3) Be certified by a licensed professional engineer or licensed professional architect, with a floodproofing certificate, that the design and methods of construction meet the requirements of this section. Refer to FEMA Technical Bulletin No. 3, Non-Residential Floodproofing - Requirements and Certification, for guidance.

§ 453-28 Accessory structures.

[Amended 8-21-2015 by Ord. No. 517; 11-17-2017 by Ord. No. 537]

A. Accessory structures shall meet the requirements of these regulations. Accessory structures that have a footprint of no more than 150 square feet may be allowed without requiring elevation or floodproofing, provided such structures meet all of the following requirements:

(1) Usable only for limited storage;

(2) Constructed with flood-damage-resistant materials, such as pressure treated lumber, below the base flood elevation;

(3) Firmly anchored to prevent flotation, collapse, and lateral movement;

(4) Electrical service and electrical fixtures shall be elevated.