Sec. 7B-3. - Warning and disclaimer of liability.
Sec. 7B-4.5. - Pre-abatement compliance investigations.
Sec. 7B-7. - Responsibilities of chief building official or designee.
Sec. 7B-8. - Variance procedure.
Sec. 7B-9. - Conditions for variances.
Sec. 7B-10. - General standards.
Sec. 7B-11. - Specific standards.
Sec. 7B-13. - Shallow flooding.
Unless specifically defined below, words or phrases used in this chapter shall be interpreted so as to give them the meaning they have in common usage and to give this chapter its most reasonable application.
"Appeal" means a request for a review of the chief building official's interpretation of any provision of this chapter or a request for a variance.
"Area of shallow flooding" means a designated AO Zone on the Flood Insurance Rate Map (FIRM). The base flood depths range from one foot (1') to three feet (3'); a clearly defined channel does not exist; the path of flooding is unpredictable and indeterminate; and, velocity flow may be evident.
"Area of special flood hazard" means the land in the floodplain within a community subject to a one percent (1%) or greater chance of flooding in any given year.
"Base flood" means the flood having a one percent (1%) chance of being equaled or exceeded in any given year.
"Basement" means any area of the building having its floor subgrade (below ground level) on all sides.
"Breakaway walls" are any type of walls, whether solid or lattice, and whether constructed of concrete, masonry, wood, metal, plastic or any other suitable building material which is not part of the structural support of the building and which is so designed as to breakaway under abnormally high tides or wave action without damage to the structural integrity of the building on which they are used or any buildings to which they might be carried by flood waters.
"Coastal high hazard area" is the area subject to high velocity waters, including coastal and tidal inundation or tsunamis. The area is designated on a Flood Insurance Rate Map (FIRM) as Zone VE.
"Development" means any manmade change to improved or unimproved real estate, including, but not limited to, buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations or storage of equipment or materials, located within the area of special flood hazard.
"Existing mobilehome park or mobilehome subdivision" means a parcel (or contiguous parcels) of land divided into two (2) or more mobilehome lots for rent or sale for which the construction of facilities for servicing the lot on which the mobilehome is to be affixed (including, at a minimum, the installation of utilities, either final site grading or the pouring of concrete pads, and the construction of streets) is completed before the effective date of the ordinance codified in this chapter.
"Expansion to an existing mobilehome park or mobilehome subdivision" means the preparation of additional sites by the construction of facilities for servicing the lots on which the mobilehomes are to be affixed (including the installation of utilities, either final site grading or pouring of concrete pads, or the construction of streets).
"Flood" or "flooding" means a general and temporary condition of partial or complete inundation of normally dry land areas from:
(a)
The overflow of inland or tidal waters; and/or
(b)
The unusual and rapid accumulation or runoff of surface waters from any source.
"Flood Insurance Rate Map (FIRM)" means the official map on which the Federal Insurance Administration has delineated the areas of flood hazards, floodways and/or the risk premium zones applicable to the community.
"Flood Insurance Study" means the official report provided by the Federal Insurance Administration that includes flood profiles, the Flood Insurance Rate Map, and the water surface elevation of the base flood.
"Floodproofing" means any combination of structural and nonstructural additions, changes or adjustments to nonresidential structures which reduce or eliminate flood damage to real estate or improved property, water and sanitary facilities, structures and their contents.
"Floodway" means the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevations more than one foot (1′).
"Highest adjacent grade" means the highest natural elevation of the ground surface prior to construction next to the proposed walls of a structure.
"Historic structure" means any structure that is:
(a)
Listed individually in the National Register or Historic Places (a listing maintained by the Department of Interior) or preliminarily determined by the Secretary of the Interior as meeting the requirements for individual listing on the National Register;
(b)
Certified or preliminarily determined by the Secretary of the Interior as contributing to the historical significance of a registered historic district or a district preliminarily determined by the Secretary to qualify as a registered historic district;
(c)
Individually listed on a state inventory or historic places in states with historic preservation programs which have been approved by the Secretary of the Interior; or
(d)
Individually listed on a local inventory of historic places in communities with historic preservation programs that have been certified either:
(1)
By an approved state program as determined by the Secretary of the Interior, or
(2)
Directly by the Secretary of the Interior in states without approved programs.
"Lowest floor" means the lowest floor of the lowest enclosed area (including basement). An unfinished or flood resistant enclosure, usable solely for parking of vehicles, building access, or storage in an area other than a basement area is not considered a building's lowest floor; provided, that such enclosure is not built so as to render the structure in violation of the applicable nonelevation design requirements of this chapter.
"Manufactured home" means a structure that is transportable in one (1) or more sections, built on a permanent chassis, or designed to be used with or without a permanent foundation when connected to the required utilities. It does not include recreational vehicles or travel trailers.
"Mean sea level" means, for purposes of the National Flood Insurance Program, the national geodetic vertical datum (NGVD) of 1929 or other datum, to which base flood elevations shown on a communities flood insurance rate map are referenced.
"New construction" means, for the purpose of determining insurance rates, structures for which the start of construction commenced on or after the effective date of the ordinance codified in this chapter and includes any subsequent improvements to such structures. For floodplain management purposes, "new construction" means structures for which the start of construction commenced on or after the effective date of the ordinance codified in this chapter and includes any subsequent improvements to such structures.
"New manufactured home park or manufactured home subdivision" means a parcel (or contiguous parcels) of land divided into two (2) or more manufactured home lots for rent or sale for which the construction of facilities for servicing the lot (including at a minimum, the installation of utilities, either final site grading or the pouring of concrete pads, and the construction of streets) is completed on or after the effective date of the ordinance codified in this chapter.
"Ready for highway use" describes a vehicle that is on its wheels or jacking system, is attached to a site only by quick disconnect type utilities and security devices, and has no permanently attached additions.
"Recreational vehicle" means a vehicle that is:
(a)
Built on a single chassis;
(b)
Four hundred (400) square feet or less when measured at the largest horizontal projection;
(c)
Designed to be self propelled or permanently towable by a light duty truck; and
(d)
Designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel, or seasonal use.
Recreational vehicles are considered dwelling structures for the purposes of implementing this chapter.
"Sand dunes" means naturally occurring accumulations of sand in ridges or mounds landward of the beach.
"Start of construction" includes substantial improvement, and means the date the building permit was issued, provided the actual start of construction, repair, reconstruction, placement, or other improvement was within one hundred eighty (180) days of the permit date. The actual start means either the first placement of permanent construction of a structure on a site, such as the pouring of slab or footings, the installation of piles, the construction of columns, or any work beyond the stage of excavation; or the placement of a manufactured home on a foundation. Permanent construction does not include land preparation, such as clearing, grading and filling; nor does it include the installation of streets and/or walkways; nor does it include excavation for a basement, footings, piers, or foundations or the erection of temporary forms; nor does it include the installation on the property of accessory buildings, such as garages or sheds not occupied as dwelling units or not part of the main structure. For a substantial improvement, the actual start of construction means the first alteration of any wall, ceiling, floor, or other structural part of a building, whether or not that alteration affects the external dimensions of the building.
"Structure" means a walled and roofed building or mobilehome that is principally above ground.
"Substantial damage" means damage of any origin sustained by a structure whereby the cost of restoring the structure to its before-damaged condition would equal or exceed fifty percent (50%) of the market value of the structure before the damage occurred.
"Substantial improvement" means any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds forty percent (40%) for residential structures and fifty percent (50%) for nonresidential structures of the market value of the structure before the start of construction of the improvement. This term includes structures which have incurred substantial damage regardless of the value or actual cost of repair work performed. Any combination of damage repair and improvement to the structure where the cost to repair the damage and construct the improvement equals or exceeds fifty percent (50%) of the market value of the structure before the start of construction of the improvement shall be considered substantial improvement.
The term does not, however, include:
(a)
Any project for improvement of a structure to correct existing violations of state or local health, sanitary or safety code specifications which have been identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions;
(b)
Any alteration of a historic structure, provided that the alteration will not preclude the structure's continued designation as a historic structure;
(c)
Construction costs necessary to comply with federally mandated requirements, including, but not limited to, requirements for handicap access for public and commercial buildings.
The value of any work excluding damage repair to be performed under a building permit issued after January 1, 1994, shall be compared to the market value of the structure at the time of permit application to calculate the percentage of the work under the permit. This percentage figure shall be added to any successive building permits that may be issued within a subsequent three (3) year period. If the combined percentage of the work performed under the building permit or permits totals forty percent (40%) or more for residential structures and fifty percent (50%) or more for nonresidential structures, this work shall constitute a substantial improvement.
"Variance" means a grant of relief from the requirements of this chapter which permits construction in a manner that would otherwise be prohibited by this chapter.
"Violation" means the failure of a structure or other development to be fully compliant with this chapter. A structure or other development shall be presumed to be in violation until the elevation certificate, other certifications, and all other evidence of compliance is provided.
(Ord. No. 5700 § 1, 2007; Ord. No. 5008 § 1, 1997; Ord. No. 4887 §§ 1, 2 and 3 (part), 1995; Ord. No. 4852 §§ 2, 3, 1995; Ord. No. 4127 § 1, 1990: Ord. No. 3575 § 1, 1986.)
The Federal Emergency Management Agency's Flood Insurance Study (FIS) for the County of Sonoma dated September 6, 2006, its accompanying Flood Insurance Rate Maps (FIRMs) and Flood Boundary and Floodway Maps (FBFMs), also dated September 6, 2006, and all subsequent amendments and/or revisions thereto, are hereby adopted by reference and declared to be a part of this chapter. This chapter applies to all areas of special flood hazard identified in the FIS and its attendant maps, and to other areas recommended to the Board of Supervisors by the floodplain administrator. The FIS, FIRMs, and FBFMs are on file at the Permit and Resource Management Department, 2550 Ventura Avenue, Santa Rosa CA 95403.
(Ord. No. 5681 § 1, 2006: Ord. No. 2918 § 3.)
Sec. 7B-3. - Warning and disclaimer of liability.
The degree of flood protection required by this chapter is considered reasonable for regulatory purposes and is based on scientific and engineering considerations. Larger floods can and will occur on rare occasions. Flood heights may be increased by man made or natural causes. This chapter does not imply that land outside the areas of special flood hazards or uses permitted within such areas will be free from flooding or flood damages. This chapter shall not create liability on the part of the county of Sonoma, any officer or employee thereof, the state of California, or the Federal Emergency Management Agency, for any flood damages that result from reliance on this chapter or any administrative decision lawfully made hereunder.
(Ord. No. 5700 § 1, 2007.)
No structure or land shall hereafter be constructed, located, extended, converted or altered without full compliance with the terms of this chapter and other applicable regulations.
(Ord. No. 2918 § 3.)
Sec. 7B-4.5. - Pre-abatement compliance investigations.
Any improvements upon a parcel which, pursuant to Federal Emergency Management Agency (FEMA) records, was claimed by the owner to have been damaged, for which there is probable cause to believe reconstruction or rehabilitation was undertaken, and for which an appropriate permit authorizing reconstruction does not exist, shall be presumed to be unlawful and subject to referral for abatement proceedings. The assessed owner shall be provided with notice of the rebuttable presumption of unlawful construction and afforded thirty (30) days to contact Sonoma County permit and resource management department to schedule a hearing to ascertain the permit status of the property. Appearance at the informal hearing shall extinguish the presumption, and be superseded by the findings of a de novo administrative hearing. The permit and resource management department shall hold the informal fact-finding hearing within thirty (30) working days after a request for a hearing is made. In the event findings are made that unlawful construction has taken place, or, in the event that an affected property owner does not request a de novo fact-finding hearing, appropriate abatement proceedings shall be commenced by the code enforcement division forthwith.
(Ord. No. 4887 § 5, 1995: Ord. No. 4111 § 2, 1989.)
All required building, grading, drainage, and similar permits shall be obtained before construction or development, including improvements, additions or repairs to existing structures, and the placement of manufactured homes, begins within any area of special flood hazard established in Section 7B-2. Application for a permit shall be made on forms furnished by the chief building official and may include, but not be limited to: plans in duplicate drawn to scale showing the nature, location, dimensions and elevations of the area in question; existing or proposed structures, fill, storage of materials, drainage facilities; and the location of the foregoing. Specifically, the following information is required:
(1)
Elevation in relation to mean sea level, of the lowest floor (including basement) of all structures;
(2)
Elevation in relation to mean sea level to which any structure has been floodproofed;
(3)
Certification by a registered professional engineer or architect licensed in the state of California that the floodproofing methods for any nonresidential structure meet the floodproofing criteria in this chapter;
(4)
Description of the extent to which any water course will be altered or relocated as a result of proposed development; and
(5)
Proof that before the onset of construction or development, all necessary permits will be received from those governmental agencies from which approval is required by federal and state law, including Section 404 of the Federal Water Pollution Control Act Amendments of 1972, 33 U.S.C. ( 1334.
(Ord. No. 5700 § 1, 2007: Ord. No. 4127 § 2, 1990: Ord. No. 4083, 1989.)
The chief building official or designee is appointed to administer and implement this chapter by granting or denying development permit applications in accordance with its provisions.
(Ord. No. 4887 § 6 (part), 1995: Ord. No. 2918 § 3.)
Sec. 7B-7. - Responsibilities of chief building official or designee.
Duties of the chief building official or designee shall include:
(a)
Permit Review.
(1)
Review all permits to determine that the permit requirements of this chapter have been satisfied;
(2)
Review all permits to determine if the proposed development would adversely affect the flood-carrying capacity of the area of special flood hazard. For purposes of this chapter, "adversely affect" means that the cumulative effect of the proposed development when combined with all other existing and anticipated development would increase the water surface elevation of the base flood more than one foot (1′) at any point;
(3)
Review all permits to determine if all other required state and federal permits have been obtained.
(b)
Use of Other Base Flood Data. When base flood elevation data has not been provided in accordance with Section 7B-2, the chief building official shall obtain, review and utilize any base flood elevation data available from a federal, state, county or other source, in order to administer this chapter.
(c)
Information to be Obtained and Maintained.
(1)
Obtain and record the actual elevation (in relation to mean sea level) of the lowest floor (including basement) of all new or substantially improved structures;
(2)
For all new or substantially improved flood proofed structures:
(i)
Verify and record the actual elevation of flood proofing (in relation to mean sea level),
(ii)
Maintain the flood proofing certifications required in Section 7B-5,
(iii)
Maintain for public inspection all records pertaining to the provisions of this chapter.
(d)
Alteration of Watercourses. Require that maintenance is provided within any altered or relocated portion of a watercourse so that the flood-carrying capacity is not diminished. Notify adjacent communities and the California Department of Water Resources prior to such alteration or relocation of a watercourse, and submit evidence of such notification to the Federal Emergency Management Agency.
(e)
Interpretation of FIRM Boundaries. Make interpretations where needed, as to the exact location of the boundaries of the areas of special flood hazards (for example, where there appears to be a conflict between a mapped boundary and actual field conditions). The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as hereinafter provided.
(f)
Base flood elevations may increase or decrease resulting from physical changes affecting flooding conditions. As soon as practicable, but not later than six (6) months after the date such information becomes available, the county of Sonoma shall notify the administrator of the changes by submitting technical or scientific data in accordance with this part. Such a submission is necessary so that upon confirmation of those physical changes affecting flooding conditions, risk premium rates and flood plain management requirements will be based upon current data.
(Ord. No. 5700 § 1, 2007; Ord. No. 4887 § 6 (part), 1995: Ord. No. 4127 § 3, 1990: Ord. No. 4083, 1989.)
Sec. 7B-8. - Variance procedure.
(a)
The chief building official shall hear and decide appeals and requests for variances from the requirements of this chapter.
(b)
The chief building official shall hear and decide appeals when it is alleged there is an error in any requirement, decision, or determination made in the enforcement or administration of this chapter.
(c)
In passing upon applications for variances, the chief building official shall consider all technical evaluations, all relevant factors, standards specified in other sections of this chapter, and:
(1)
The danger that materials may be swept onto other lands to the injury of others;
(2)
The danger to life and property due to flooding or erosion damage;
(3)
The susceptibility of the proposed facility and its contents to flood damage and the effect of such damage on the individual owner;
(4)
The safety of access to the property in times of flood for ordinary and emergency vehicles;
(5)
The expected heights, velocity, duration, rate of rise, sediment transport of the flood waters and the effects of wave action, if applicable, expected at the site; and
(6)
The costs of providing governmental services during and after flood conditions, including maintenance and repair of public utilities and facilities such as sewer, gas, electrical, and water systems, and streets and bridges.
(d)
Generally, variances may be issued for new construction and substantial improvements to be erected on a lot of one-half acre or less in size contiguous to and surrounded by lots with existing structures constructed below the base flood level, providing subsections (c)(1) through (6) in this section have been fully considered. As the lot size increases beyond the one-half acre, the technical justification required for issuing the variance increases.
(e)
Upon consideration of the factors of this section and the purposes of this chapter, the chief building official may attach such conditions to the granting of variances as he or she deems necessary to further the purposes of this chapter.
(f)
The chief building official shall maintain the records of all appeal actions and report any variances to the Federal Emergency Management Agency upon request.
(Ord. No. 5700 § 1, 2007; Ord. No. 2918 § 3.)
Sec. 7B-9. - Conditions for variances.
(a)
Variances may be issued for the reconstruction, rehabilitation or restoration of structures listed on the National Register of Historic Places or the State Inventory of Historic Places, without regard to the procedures set forth in the remainder of this section.
(b)
Variances shall not be issued within any designated floodway if any increase in flood levels during the base flood discharge would result.
(c)
Variances shall only be issued upon a determination that the variance is the minimum necessary, considering the flood hazard, to afford relief.
(d)
Variances shall only be issued upon:
(1)
A showing of good and sufficient cause;
(2)
A determination that failure to grant the variance would result in exceptional hardship to the applicant; and
(3)
A determination that the granting of a variance will not result in increased flood heights, additional threats to public safety, extraordinary public expense, create nuisances, cause fraud on or victimization of the public as identified in Section 7B-8, or conflict with existing local laws or ordinances.
(e)
Any applicant to whom a variance is granted shall be given written notice that the structure will be permitted to be built with a lowest floor elevation below the base flood elevation and that the cost of flood insurance will be commensurate with the increased risk resulting from the reduced lowest flood elevation.
(Ord. No. 2918 § 3.)
Sec. 7B-10. - General standards.
In all areas of special flood hazards the following standards are required:
(a)
Anchoring.
(1)
All new construction and substantial improvements shall be designed (or modified) and adequately anchored to prevent flotation, collapse or lateral movement of the structure, resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy.
(2)
All mobilehomes shall be anchored to resist flotation, collapse, or lateral movement by providing over-the-top and frame ties to ground anchors. Specific requirements shall be that:
(i)
Over-the-top ties be provided at each of the four (4) corners of the mobilehome, with two (2) additional ties per side at intermediate locations, with manufactured homes less than fifty feet (50') long requiring one additional tie per side;
(ii)
Frame ties be provided at each corner of the home with five (5) additional ties per side at intermediate points, with manufactured homes less than fifty feet (50') long requiring four (4) additional ties per side;
(iii)
All components of the anchoring system be capable of carrying a force of four thousand eight hundred (4,800) pounds; and
(iv)
Any additions to the manufactured home be similarly anchored.
(b)
Construction Materials and Methods.
(1)
All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.
(2)
All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.
(3)
All new construction and substantial improvements with fully enclosed areas below the lowest floor (including basement) that are subject to flooding shall be designed to automatically equalize hydrostatic 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 licensed in the state of California or meet or exceed the following minimum criteria:
(i)
Two (2) openings having a total net area of not less than one (1) square inch for every square foot of enclosed area subject to flooding shall be provided; and
(ii)
The bottom of all openings shall be no higher than one foot (1') above grade. 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.
(4)
All new construction and substantial improvements shall be constructed with electrical, heating, ventilation, plumbing and air conditioning equipment and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
(c)
Utilities.
(1)
All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the systems;
(2)
New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the systems and discharge from the systems into flood waters; and,
(3)
On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.
(d)
Subdivision Proposals and Other Proposed New Development.
(1)
All subdivision proposals and other proposed new development shall meet the permit requirements of this chapter;
(2)
All subdivision proposals and other proposed new development shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage;
(3)
All subdivision proposals and other proposed new development shall have adequate drainage provided to reduce exposure to flood damage; and
(4)
Base flood elevation data shall be provided for subdivision proposals and other proposed new development (including proposals for manufactured home parks and subdivisions) that contain at least fifty (50) lots or five (5) acres (whichever is less).
(Ord. No. 5700 § 1, 2007; Ord. No. 4887 §§ 3 (part), 7, 1995; Ord. No. 3826, 1988.)
Sec. 7B-11. - Specific standards.
In all areas of special flood hazard where base flood elevation data has been provided as set forth in Section 7B-2 or Section 7B-7, the following provisions are required:
(a)
Residential Construction. New construction and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated above the base flood elevation at least twelve inches (12″).
(b)
Nonresidential Construction. New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall either have the lowest floor, including basement, elevated at least twelve inches (12″) above base flood elevation; or together with attendant utility and sanitary facilities shall:
(1)
Be floodproofed to twelve inches (12″) above the base flood elevation so that the structure is watertight with walls substantially impermeable to the passage of water;
(2)
Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy;
(3)
Have a registered professional engineer or architect licensed in the state of California develop and/or review structural design, specifications, and plans for construction. Have a registered professional engineer or architect licensed in the state of California certify that the standards of this subsection are satisfied. Such certification shall be provided to the official as set forth in Section 7B-5.
(c)
Manufactured Homes.
(1)
Manufactured homes shall be anchored in accordance with Section 7B-10.
(2)
New manufactured home parks and manufactured home subdivisions; expansion to existing manufactured home parks and manufactured home subdivisions; existing manufactured home parks and manufactured home subdivisions where the repair, reconstruction or improvement of the streets, utilities and pads equals or exceeds fifty percent (50%) of value of the streets, utilities and pads before the repair, reconstruction or improvements has commenced; manufactured homes not placed in a manufactured home park or manufactured home subdivision; and existing manufactured home parks or manufactured home subdivisions in which a manufactured home has incurred (substantial damage( as a result of a flood or in which new construction or (substantial improvement( of a manufactured home is proposed, require:
(i)
Permanent foundations are elevated so that the lowest floor of the manufactured home will be at least twelve inches (12″) above the base flood elevation specified on the FIRM (Flood Insurance Rate Map);
(ii)
Adequate surface drainage and access for a hauler are provided; and
(iii)
In the instance of elevation on piles, that
(a)
Lots are large enough to permit steps,
(b)
Piles are placed in stable soil no more than ten feet (10′) apart, and
(c)
Reinforcement is provided for piles extending more than six feet (6′) above the ground level.
(d)
Coastal High Hazard Area.
(1)
All buildings or structures shall be located landward out of reach of the mean high tide.
(2)
The placement of manufactured homes shall be prohibited, except in an existing manufactured home park or manufactured home subdivision.
(3)
The alteration of sand dunes which would result in an increase of potential flood damage shall be prohibited.
(4)
Construction Requirements.
(i)
Elevation. All buildings or structures shall be elevated so that the lowest horizontal supporting member is located no lower than the base flood elevation, with all space below the lowest horizontal supporting member open so as not to impede the flow of water, except for breakaway walls.
(ii)
Structural Support.
(a)
All buildings or structures shall be securely anchored on piles or columns.
(b)
Piles or columns used as structural support shall be designed and anchored so as to withstand all impact forces and buoyancy factors of the base flood.
(c)
There shall be no fill used for structural support.
(iii)
Space Below the Lowest Floor.
(a)
Any alteration, repair, reconstruction or improvement to a structure started after the enactment of the ordinance codified in this chapter shall not enclose the space below the lowest floor unless breakaway walls are used as provided for in this section.
(b)
Breakaway walls may be allowed below the base flood elevation provided they are not a part of the structural support of the building and are designed so as to breakaway, under abnormally high tides or wave action, without damage to the structural integrity of the building on which they are to be used.
(c)
If breakaway walls are utilized, such enclosed space shall not be used for habitation.
(d)
For the purposes of this section, a breakway wall shall have a design safe loading resistance of not less than ten (10) and no more than twenty (20) pounds per square foot. Use of breakway walls that exceed a design safe loading resistance of twenty (20) pounds per square foot (either by design or when so required by local or state codes) shall be permitted if a registered professional engineer or architect certifies that the designs proposed meet the following conditions:
(i)
Breakaway wall collapse shall result from a water load less than that which would occur during the base flood; and,
(ii)
The elevated portion of the building and supporting foundation system shall not be subject to collapse, displacement, or other structural damage due to the effects of wind and water loads acting simultaneously on all building components (structural and non-structural). Water loading values used shall be those associated with the base flood. Wind loading values used shall be those required by applicable state or local building standards. Such enclosed space shall be useable solely for parking of vehicles, building access, or storage.
(iv)
Certification. A registered professional engineer or architect licensed in the state of California shall develop and/or review structural design, specifications, and plans for construction and shall certify that the design and methods of construction to be used are in accordance with accepted standards of practice for meeting the provisions of this subsection. Such certification shall be provided to the official as set forth in Section 7B-5.
(e)
Recreational Vehicles. All recreational vehicles shall either:
(1)
Be on the site for fewer than one hundred eighty (180) consecutive days;
(2)
Be fully licensed and ready for highway use; or
(3)
Comply with all provisions of this chapter, including but not limited to Sections 7B-5, 7B-10, and 7B-11.
(Ord. No. 5700 § 1, 2007; Ord. No. 5224 § 1, 2000; Ord. No. 4887 § 8, 1995: Ord. No. 3575 § 3, 1986; Ord. No. 2918 § 3.)
Located within areas of special flood hazard established in Section 7B-2 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of flood waters which carry debris, potential projectiles, and erosion potential, the following provisions apply:
(1)
Prohibit encroachments, including fill, new construction, substantial improvements, and other development within the adopted floodway unless it has been demonstrated through hydrologic and hydraulic analysis performed in accordance with standard engineering practice and certified by a registered professional engineer or architect licensed in the state of California that the proposed encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge.
(2)
If paragraph (1) hereof is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this chapter.
(3)
Prohibit the placement of any manufactured homes, except in an existing manufactured home park or existing manufactured home subdivision.
(Ord. No. 5700 § 1, 2007; Ord. No. 4887 § 3 (part), 1995; Ord. No. 2918 § 3.)
Sec. 7B-13. - Shallow flooding.
Located within the areas of special flood hazard established in Section 7B-2 are areas designated as shallow flooding. These areas have special flood hazards associated with base flood depths of one foot (1′) to three feet (3′) where a clearly defined channel does not exist and where the path of flooding is unpredictable and indeterminate; therefore, the following provisions apply:
(1)
All new construction and substantial improvements shall be provided with adequate drainage paths around structures on slopes to guide flood waters around and away from the proposed structures;
(2)
All new construction and substantial improvements of residential structures have the lowest floor, including basement, elevated above the highest adjacent grade to at least twelve inches (12′) above the depth number specified on the community(s FIRM (or at least two feet if no depth number is specified);
(3)
All new construction and substantial improvements of nonresidential structures shall:
(i)
Have the lowest floor, including basement, elevated above the highest adjacent grade to at least twelve inches (12′) above the depth number specified on the FIRM (or at least two (2) feet if no depth number is specified), or
(ii)
Together with attendant utility and sanitary facilities be completely floodproofed to at least twelve inches (12′) above the depth number specified on the FIRM (or at least two (2) feet if no depth number is specified) so that any space below the depth number specified on the FIRM (or at least two (2) feet if no depth number is specified) is watertight with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads and effects of buoyancy.
(Ord. No. 5700 § 1, 2007; Ord. No. 4887 § 9, 1995: Ord No. 3826, 1988.)