Fort Walton Beach Ordinance — 1126--Flood Damage Prevention — reading text

is at or above the regulatory flood level. D. Adequate surface drainage and easy access for a mobile home hauler are provided. E. Load-bearing foundation supports, such as piers or pilings, must be placed on stable soil or concrete foot- ings not more than ten feet apart, and if the support height is greater than seventy-two inches, the support must contain steel reinforcement. (2) The location or relocation of a manufactured home (mobile home) shall be allowed, provided that: A. Any manufactured home (mobile home) site rental or leasing agreement or any contract for and deed of sale shall clearly state that the land in question has been designated as part of a Flood Fringe District and may be subject to flooding. B. Any manufactured home (mobile home) moved into or relocated within an existing mobile home park shall be anchored in accordance with paragraphs (c)(1)A. and B. hereof. - C. The owner, operator or manager of an_ existing manufactured home (mobile home) park shall file with the County Civil Defense Office an evacuation plan indicating alternate vehicular access and escape routes. D. Easy access for a manufactured home (mobile home) hauler shall be provided. (Ord. 658. Passed 7-27-76; Ord. 658.1. Passed 9-4-76; Ord. 910. Passed 11-11-86.) (3) All new subdivision proposals and proposals for other devel- opments (including proposals for manufactured home parks and subdivisions) greater than fifty lots or five acres, - whichever is less, shall provide the base flood elevation data on the plate (Ord. 968. Passed 11-24-87.) 1412.07 COASTAL HIGH HAZARD DISTRICTS (CHHD). Ca) Applicability. This section shall apply to all areas designated as Coastal High Hazard Districts (CHHD) on the Official Zoning Map. (bo) Requirements for Development of CHHD. (1) Except as otherwise provided herein, all new construction and substantial improvements within a designated CHHD shall: A. Be located landward of the mean high tide; B. Be elevated on adequately anchored piles or columns so that the structural members ‘of the lowest floor are elevated at least to the regulatory flood elevation and securely anchored to such piles or columns; 1987-A Replacement ’ 1412.07 BUILDING AND HOUSING CODE - 32 (2) (3) (4) (5) C. Have the space below the lowest floor free of obstruc- tion or constructed with breakaway walls intended to collapse under stress without jeopardizing the structural integrity of the building, such breakaway walls to meet the requirements of Section 1412.09; D. Be designed and constructed so as to minimize the im- pact and effect of abnormally high tides, wind-driven water or waves on the building; and E. Be certified by a registered professional engineer or architect through his or her submission of an "elevation certificate," noting the design, specification and plans for construction, and by identifying the elevation of the bottom of the lowest structural member of the lowest floor of all new and substantially improved structures. All buildings under construction in the CHHD~ shall have vertical rods from the foundation to the tie beam in all walls that are more than three blocks in height. No. 5 vertical rods shall be installed in all corners and No. 4 rods shall be installed every eight feet on center. “ Fill shall not be used for structural support within a CHHD. All pilings, columns and the attached structures shall be anchored to resist flotation, collapse and lateral movement due to the effect of wind and water loads acting simultan- eously on all building components. The anchoring and sup- port system shall be designed with the wind and water loading vaives which equal or exceed the 100-year mean recurrence interval (one percent annual chance flood). Lattice work or decorative screening below the base elevation shall be allowed, provided the same are not part of the structural support of the building and are designed in accordance with Section 1412.09. (c) Manufactured Homes Within a CHHD. (1) (2) No new manufactured home (mobile home) park, expansion of ~ an existing manufactured home (mobile home) park or place- ment of a manufactured home (mobile home) not in a manufactured home (mobile park) shall be allowed within a designated CHIID. If a manufactured home (mobile home): location or relocation is not deemed to constitute the expansion of an existing manufactured home (mobile home) park, as set forth in para- graph (c)(1) hereof, the location or relocation shall be al- lowed, provided that: A. Any manufactured home (mobile home) site rental or leasing agreement or any contract for and deed of sale shall clearly state that the land in question has been designated as part of a Coastal High Hazard District and may be subject to flooding. B. Any manufactured home (mobile home) moved into or relocated within an existing manufactured home (mobile home) park shall be anchored in accordance with the provisions of Section 1412.06. 1987-A Replacement 33 Floodplain Regulations 1412.08 C. The owner, operator or manager of an_ existing manufactured home (mobile home) park shall file with the County Civil Defense Office an evacuation plan indicating alternate vehicular access and escape routes. D. Easy access for a manufactured home (mobile home) hauler shall be provided. (Ord. 658. Passed 7-27-76; Ord. 658.3. Passed 4-25-78; Ord. 910. Passed 11-11-86.) 1412.08 FLOODPROOFING. (a) Minimum Floodproofing Requirements. Wherever any of the provi- _sions of this chapter requires that a building be floodproofed or specifies that floodproofing may be used as an alternative to elevating a structure above the regulatory flood level, floodproofing shall be deemed to include all of the following: ~- (1) (2) (3) (4) (5) (6) Wherever possible, ‘the location, construction and installation of all electrical and gas utility systems shall be done in such a manner as to assure the continuing functioning of those systems in the event of a regulatory flood. The location, construction and installation of all potable water supply systems shall be done in such a manner as to prevent contamination from flood waters during the regula- tory flood. No water supply well shall be located within the foundation walls of a building or structure used for human habitation, medical or educational services, food processing or public services. Approved backflow preventers or devices shall be installed on main water service lines, at water wells and at all build- ing entry locations to protect the system from backflow or back siphonage of flood waters or other contaminants. Sanitary sewer and storm drainage systems that have open- ings below the regulatory flood elevation shall be equipped with automatic backwater valves or other automatic backflow devices that are installed in each discharge line passing through a building exterior wall. Sanitary sewer systems, including septic tank systems, that are required to remain in operation during a flood shall be provided with a sealed holding tank and the necessary isola- tion and diversion piping, pumps, ejectors and appurte- nances required to prevent sewage discharge during a flood. The holding tank shall be sized for storage of at least two days demand. A registered professional engineer or architect shall certify that any new construction or substantial improvement has been designed to withstand the flood depths, pressure, velocities: and impact and uplift forces associated with the regulatory flood at the location of the building. 1987-A Replacement 1412.09 BUILDING AND HOUSING CODE . 34 (b) Approval of Floodproofing. Prior to construction, plans for any structure that is requiréd to be floodproofed must be submitted to the City Engineer for approval. The City Engineer will review the plans for compli- ance with paragraph (a)(6) hereof, for general compliance techniques specified in the United States Army Corps of Engineers publication entitled Floodproofing Regulations, June 1972, GPO: 19730-505-026, and for compli- ance with any other applicable building codes or regulations. The City Engineer shall approve, reject or recommend modification of the plans within fifteen days from the date of receipt of the plans. (Ord. 658. Passed 7-27-76.) 1412.09 BREAKAWAY WALLS. (a) Minimum Requirements. Wherever any of the provisions of this chapter provides for a breakaway wall to be located below the regulatory flood level, specifications must be met by the engineer or architect pre- paring the plans. This space below the lowest floor shall be free either of obstruction or shall be constructed with nonsupporting breakaway walls, open wood lattice work or insect screening intended to collapse under wind and water loads without causing collapse, displacement or other structural damage to the elevated portion of the building or the supporting foundation system. For the purposes of this section, a breakaway wall shall have a design safe loading resistance of not less than ten nor more than twenty pounds per square foot. Use of breakaway walls which exceed a design~safe loading resistance of twenty pounds per square foot may be permitted only if certified by a registered professional engineer or architect. Standard C practice is to use this design-safe loading resistance weight as a wind load on a vertical panel facing directly into the wind. This load would correspond to a wind speed of about 100 miles per hour and should be the minimum load which would not cause the panels to break away. The maximum load which would not cause failure of the superstructure is more difficult to determine, but is probably about fifty. to seventy-five pounds per square foot. Designation of this limit should be based on such factors ~ as material, cross-section and spacing of pilings or columns upon which the structure sits, the elevation above the ground and other assumed loadings on the structure. Such enclosed space shall be usable solely for parking of vehicles, building access or storage. (Ord. 910. Passed 11-11-86.) (ob) Design of Enclosed Areas. Fully enclosed areas below the lowest floor, that are subject to flooding, in all new construction and substantial improvements in the City, shall be designed to automatically equalize hydro- static flood forces on exterior walls by allowing for the entry and exit of flood waters. Designs for meeting this requirement must either be certified by a registered professional engineer or architect or meet or exceed the following minimum criteria: A minimum of two openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided; the bottom of all openings shall be no higher than one foot above grade; and openings may be equipped with screens, louvers, valves or other coverings or devices, provided that they permit the automatic entry and exit of flood waters. } 1987-A Replacement 384A Floodplain Regulations 1412.10 (b)° Approval. Prior to construction, plans for any structure that will have breakaway walls must be submitted to the City Engineer for approval. The City Engineer will review the plans for compliance with subsection (a) hereof. The City Engineer shall approve, reject or recommend modification of the plans within fifteen days from the date of the receipt of the plans. (Ord. 968. Passed 11-24-87.) 1412.10 VARIANCES. (a) Upon the submission of a written application to the Board of Adjustment, a variance may be granted permitting the erection of structures with the lowest floor elevation, including the basement, lower than the regulatory flood elevation, if all of the following criteria are met: (1) The property on which the structure is to be erected is an isolated lot of one-half acre or less, contiguous to and sur- rounded by existing structures constructed b@low: such re- quired first floor elevation, or a structure listed on the National Register of Historic Places or a State Inventory of