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CHAPTER 18: FLOODPLAIN MANAGEMENT
ARTICLE I. GENERAL PROVISIONS
18-3. Flood loss reduction methods
18-4. Breakaway walls
18-5. Mobile homes; start of construction
18-6. Description of substantial improvements
18-7. Presumption of violation
18-8. Applicable lands
18-9. Basis for establishing the areas of special flood hazard
18-10. Compliance; violation a misdemeanor
18-11. Abrogation; effect of other ordinances
18-13. Warning and disclaimer of liability
ARTICLE II. ADMINISTRATION
18-20. Designation of the floodplain administrator
18-21. Duties and responsibilities of the floodplain administrator
ARTICLE III. PERMIT, APPEAL AND VARIANCE PROCEDURES
18-25. Issuance of development permit
18-26. Appeal board
18-27. Conditions for variances
ARTICLE IV. PROVISIONS FOR FLOOD HAZARD REDUCTION
18-35. Standards of construction
18-36. Standards for utilities
18-37. Standards for subdivisions
18-37.1. Standards for manufactured homes
18-37.2. Standards for recreational vehicles
18-39. Coastal high hazard areas
18-40. Flood-related erosion-prone area
ARTICLE I. GENERAL PROVISIONS
(A) This chapter is adopted pursuant to the authority conferred by Cal. Gov't Code sections 65302, 65560 and 65800 to adopt regulations designed to promote the public health, safety and general welfare.
(B) The City Council finds as follows:
(1) The flood hazard areas of the city are subject to periodic inundation which results in loss of life and property, health and safety hazards, disruption of commerce and governmental services, extraordinary public expenditures for flood protection and relief, and impairment of tax base, all of which adversely affect the public health, safety and general welfare.
(2) These flood losses are caused by uses that are inadequately elevated, flood proofed or protected from flood damage. The cumulative effect of obstructions in areas of special flood hazards that increase flood heights and velocities also contribute to the flood loss.
(C) The purpose of this chapter is to promote public health, safety and general welfare, and to minimize public and private losses due to flood conditions in specific areas by provisions designed to:
(1) Protect human life and health;
(2) Minimize expenditure of public money for costly flood control projects;
(3) Minimize the need for rescue and relief efforts associated with flooding and generally undertaken at the expense of the general public;
(4) Minimize prolonged business interruptions;
(5) Minimize damage to public facilities and utilities such as water and gas mains; electric, telephone and sewer lines; and streets and bridges located in areas of special flood hazard;
(6) Help maintain a stable tax base by providing for the sound use and development of areas of special flood hazard so as to minimize future blighted areas caused by flood damage;
(7) Ensure that potential buyers are notified that property is in an area of special flood hazard; and
(8) Ensure that those who occupy the areas of special flood hazard assume responsibility for their actions.
(D) In order to accomplish its purposes, this chapter includes methods and provisions to:
(1) Restrict or prohibit uses which are dangerous to health, safety and property due to water or erosion hazards, or which result in damaging increases in erosion or flood heights or velocities;
(2) Require that uses vulnerable to floods, including facilities which serve such uses, be protected against flood damage at the time of initial construction;
(3) Control the alteration of natural floodplains, stream channels and natural protective barriers, which help accommodate or channel flood waters;
(4) Control filling, grading, dredging and other development which may increase flood damage; and
(5) Prevent or regulate the construction of flood barriers which will unnaturally divert floodwaters or which may increase flood hazards in other areas.
(`64 Code, Sec. 35-1) (Ord. No. 2426, 2640)
For the purposes of this chapter, the following words shall have the following meanings:
ACCESSORY BUILDING - A building that is incidental and subordinate to the principal building on the parcel of land on which it is located.
APPEAL - A request for a review of the flood engineer's interpretation of any provision of this chapter or a request for a variance.
AREA OF SPECIAL FLOOD HAZARD - The land in the floodplain within the city subject to a 1% or greater chance of flooding in any given year.
BASE FLOOD - The flood having a 1% chance of being equaled or exceeded in any given year; also called the "100 year flood."
BASEMENT - Any area of a building having its floor subgrade (below ground level) on all sides.
BREAKAWAY WALLS - Any type of walls, whether solid or lattice, and whether constructed of concrete, masonry, wood, metal, plastic or any other suitable building material that is not part of the structural support of the building and that is designed to break away under abnormally high tides or wave action without causing any damage to the structural integrity of the building on which they are used or any buildings to that they might be carried by flood waters.
BUILDING - See STRUCTURE.
COASTAL HIGH HAZARD AREA - The area subject to high velocity waters, including coastal and tidal inundation or tsunamis and designated on a flood insurance rate map (FIRM) as zone V1-V30, VE or V.
DEVELOPMENT - 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 located within the area of special flood hazard.
DUNE - A continuous or nearly continuous mound or ridge of sand with relatively steep seaward and landward slopes immediately landward and adjacent to the beach and subject to erosion and overtopping from high tides and waves during major coastal storms. The inland limit of a primary frontal dune occurs at the point where there is a distinct change from a pronounced mound of sand to a relatively mild slope.
ENCROACHMENT - The advance or infringement of uses, plan growth, fill, excavation, buildings, permanent structures or development into a floodplain, which may impede or alter the flow capacity of a floodplain.
EXISTING MANUFACTURED HOME PARK or SUBDIVISION - A manufactured home park or subdivision for which the construction of facilities for servicing the lots on which the manufactured homes are to be affixed (including, at a minimum, the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads) is completed before the effective date of the floodplain management regulations adopted by the city.
EXPANSION TO AN EXISTING MANUFACTURED HOME PARK or SUBDIVISION - The preparation of additional sites by the construction of facilities to serve the lots on which the manufactured homes are to be affixed (including the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads).
FLOOD, FLOODING or FLOOD WATER -
(1) A general and temporary condition of partial or complete inundation of normally dry land areas from the overflow of inland or tidal waters; the unusual and rapid accumulation or runoff of surface waters from any source; and/or mudslides (i.e., mudflows); and
(2) The condition resulting from flood-related erosion.
FLOOD BOUNDARY and FLOODWAY MAP (FBFM) - The official maps upon which the Federal Emergency Management Agency or Federal Insurance Administration have delineated both the area of flood hazard and the floodway.
FLOOD INSURANCE RATE MAP (FIRM) - The official map on which the Federal Emergency Management Agency or Federal Insurance Administration has delineated both the areas of special flood hazards and the risk premium zones applicable to the community.
FLOOD INSURANCE STUDY - The official report provided by the Federal Insurance Administration that includes flood profiles, the flood insurance rate map, the flood boundary and floodway map, and the water surface elevation of the base flood.
FLOOD RELATED EROSION - The collapse or subsidence of land along the shore of a lake or other body of water as a result of undermining caused by waves or currents of water exceeding anticipated cyclical level or suddenly caused by an unusually high water level in a natural body of water, accompanied by a severe storm, or by an unanticipated force of nature, such as a flash flood or an abnormal tidal surge, or by some similarly unusual and unforeseeable event which results in flooding.
FLOODPLAIN OR FLOOD-PRONE AREA - Any land area susceptible to being inundated by water from any source. (See FLOOD, FLOODING, or FLOOD WATER.)
FLOODPLAIN ADMINISTRATOR - The individual appointed to administer and enforce the floodplain management regulations.
FLOODPLAIN MANAGEMENT - The operation of an overall program of corrective and preventive measures for reducing flood damage, and preserving and enhancing, when possible, natural resources in the floodplain, including, but not limited to, emergency preparedness plans, flood control works and floodplain management regulations and open space plans.
FLOODPLAIN MANAGEMENT REGULATIONS - This chapter, zoning ordinances, subdivision regulations, building codes, health regulations, special purpose ordinances (such as grading and erosion control) and other applications of police power, which control development in flood-prone areas. This term describes federal, State or local regulations or any combination thereof that provides standards for preventing and reducing flood loss and damage.
FLOODPROOFING - Any combination of structural and nonstructural additions, changes, or adjustments to structures that reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures and their contents. (Refer to FEMA Technical Bulletins TB 1-93, TB 3-93, and TB 7-93 for guidelines on dry and wet flood proofing.)
FLOODWAY - 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 elevation more than one foot; also called "regulatory floodway."
FRAUD and VICTIMIZATION - As related to section 18-27 (Conditions for variances) of this chapter, the variance granted must not cause fraud on or victimization of the public. In examining this requirement, the decision-making body will consider the fact that every newly constructed building adds to government responsibilities and remains a part of the community for 50 to 100 years. Buildings that are permitted to be constructed below the base flood elevation are subject during all those years to increased risk of damage from floods, while future owners of the property and the community as a whole are subject to all the costs, inconvenience, danger and suffering those increased flood damages bring. In addition, future owners may purchase the property, unaware that it is subject to potential flood damage, and can be insured only at very high flood insurance rates.
FUNCTIONALLY DEPENDENT USE - A use that cannot perform its intended purpose unless located or carried out in close proximity to water including only docking facilities or port facilities that are necessary for the loading and unloading of cargo or passengers, and shipbuilding and ship repair facilities, but not including long-term storage or related manufacturing facilities.
HARDSHIP - As related to section 18-27 (Conditions for variances) of this chapter, the exceptional hardship that would result from a failure to grant the requested variance. The city requires that the variance be exceptional, unusual and peculiar to the property involved. Mere economic or financial hardship alone is not exceptional. Inconvenience, aesthetic considerations, physical handicaps, personal preferences, or the disapproval of one's neighbors likewise cannot, as a rule, qualify as an exceptional hardship. All of these problems can be resolved through other means without granting a variance, even if the alternative is more expensive or requires the property owner to build elsewhere or put the parcel to a different use than originally intended.
HIGHEST ADJACENT GRADE - The highest natural elevation of the ground surface prior to construction next to the proposed walls of a structure.
HISTORIC STRUCTURE - Any structure that is:
(1) Listed individually in the National Register of 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;
(2) 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;
(3) Individually listed on a state inventory of historic places in states with historic preservation programs which have been approved by the Secretary of the Interior; or
(4) Individually listed on a local inventory of historic places in communities with historic preservation programs that have been certified either by an approved state program as determined by the Secretary of the Interior or directly by the Secretary of the Interior in states without approved programs.
LEVEE - A manmade structure, usually an earthen embankment, designed and constructed in accordance with sound engineering practices to contain, control or divert the flow of water so as to provide protection from temporary flooding.
LOWEST FLOOR - The lowest floor of the lowest enclosed area, including basement (see basement definition).
(1) An unfinished or flood resistant enclosure below the lowest floor that is 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 it conforms to applicable non-elevation design requirements, including, but not limited to:
(a) The wet flood-proofing standard in article 4, section 18-35(C)(3);
(b) The anchoring standards in article 4, section 18-35(A);
(c) The construction materials and methods standards in section 18-35(B); and
(d) The standards for utilities in section 18-36.
(2) For residential structures, all subgrade-enclosed areas are prohibited as they are considered to be basements (see "basement" definition). This prohibition includes below-grade garages and storage areas.
MANUFACTURED HOME - A structure, transportable in one or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when attached to the required utilities. The term "manufactured home" does not include a "recreational vehicle."
MANUFACTURED HOME PARK OR SUBDIVISION - A parcel (or contiguous parcels) of land divided into two or more manufactured home lots for rent or sale.
MARKET VALUE - Determined by estimating the cost to replace the structure in new condition and adjusting that cost figure by the amount of depreciation which has accrued since the structure was constructed. The cost of replacement of the structure shall be based on a square foot cost factor determined by reference to a building cost estimate guide recognized by the building and construction industry. The amount of depreciation shall be determined by taking into account the age and physical deterioration of the structure and functional obsolescence as approved by the floodplain administrator, but shall not include economic or other forms of external obsolescence. Use of replacement costs or accrued depreciation factors different from those contained in recognized building cost estimating guides may be considered only if such factors are included in a report prepared by an independent professional appraiser and supported by a written explanation of the differences.
MEAN SEA LEVEL - 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 community's flood insurance rate map are referenced.
NEW CONSTRUCTION - For floodplain management purposes, structures for which the "start of construction," commenced on or after March 15, 1988, and includes any subsequent improvements to such structures.
NEW MANUFACTURED HOME PARK OR SUBDIVISION - A manufactured home park or subdivision for which the construction of facilities for servicing the lots on which the manufactured homes are to be affixed (including at a minimum, the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads) is completed on or after April 14, 1988.
OBSTRUCTION - Includes, but is not limited to, any dam, wall, wharf, embankment, levee, dike, pile, abutment, protection, excavation, channelization, bridge, conduit, culvert, building, wire, fence, rock, gravel, refuse, fill, structure, vegetation or other material in, along, across or projecting into any watercourse which may alter, impede, retard or change the direction and/or velocity of the flow of water, due to its location, its propensity to snare or collect debris carried by the flow of water, or its likelihood of being carried downstream.
ONE-HUNDRED YEAR FLOOD or "100-YEAR FLOOD" - (See "Base flood.")
PUBLIC SAFETY and NUISANCE - As related to section 18-27 (Conditions for variance) of this chapter, the granting of a variance must not result in anything that is injurious to safety or health of an entire community or neighborhood, or any considerable number of persons, or unlawfully obstructs the free passage or use, in the customary manner, of any navigable lake, or river, bay, stream, canal or basin.
RECREATIONAL VEHICLE - A vehicle which is:
(1) Built on a single chassis;
(2) Four hundred square feet or less when measured at the largest horizontal projection;
(3) Designed to be self-propelled or permanently towable by a light-duty truck; and
(4) Designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel, or seasonal use.
REGULATORY FLOODWAY - 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 elevation more than one foot.
REMEDY A VIOLATION - To bring the structure or other development into compliance with State or local floodplain management regulations or, if this is not possible, to reduce the impacts of its noncompliance. Ways that impacts may be reduced include protecting the structure or other affected development from flood damages, implementing the enforcement provisions of this chapter or otherwise deterring future similar violations, or reducing State or federal financial exposure with regard to the structure or other development.
RIVERINE - Relating to, formed by, or resembling a river (including tributaries) stream, brook, etc.
SAND DUNES - Naturally occurring accumulations of sand in ridges or mounds landward of the beach.
SPECIAL FLOOD HAZARD AREA (SFHA) - An area having special flood or flood-related erosion hazards, and shown on a FHBM or FIRM as zone A, AO, A1-30, AE, A99, AH, Vl-V30, VE, or V.
START OF CONSTRUCTION - Includes substantial improvement and other proposed new development and means the date the building permit was issued, provided the actual start of construction, repair, reconstruction, rehabilitation, addition, placement, or other improvement was within 180 days from the date of the permit. 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; not 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 - A walled and roofed building or mobile home that is principally aboveground, as well as a manufactured home.
SUBSTANTIAL DAMAGE - Damage of any origin sustained by a structure whereby the cost of restoring the structure to its before damaged condition would equal or exceed 50% of the market value of the structure before the damage occurred.
SUBSTANTIAL IMPROVEMENT - Any reconstruction, rehabilitation, addition, or other proposed new development of a structure, the cost of which equals or exceeds 50% of the market value of the structure before the start of construction of the improvement. This term includes structures that have incurred substantial damage, regardless of the actual repair work performed. The term does not, however, include either:
(1) 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; or
(2) Any alteration of an historic structure, provided that the alteration will not preclude the structure's continued designation as an historic structure.
VIOLATION - The failure of a structure or other development to fully comply with city's floodplain management regulations.
WATER SURFACE ELEVATION - The height, in relation to the National Geodetic Vertical Datum (NGVD) of 1929 (or other datum, where specified) of floods of various magnitudes and frequencies in the floodplains of coastal or riverine areas.
WATERCOURSE - A lake, river, creek, stream, wash, arroyo, channel or other topographic feature on or over which waters flow at least periodically. WATERCOURSE includes specifically designated areas in which substantial flood damage may occur.
(`64 Code, Sec. 35-2) (Ord. No. 2426, 2640, 2783)
To accomplish its purposes, this chapter includes methods and provisions for:
(A) Restricting or prohibiting uses that are dangerous to health, safety, and property due to water or erosion hazards, or that result in increases in erosion or in flood heights or velocities;
(B) Requiring that uses vulnerable to floods, including facilities that serve such uses, be protected against flood damage at the time of initial construction;
(C) Controlling the alteration of natural floodplains, stream channels, and natural protective barriers, that help accommodate or channel flood waters;
(D) Controlling, filling, grading, dredging, and other development that may increase flood damage; and
(E) Preventing or regulating the construction of flood barriers that will unnaturally divert flood waters or that may increase flood hazards in other areas.
(`64 Code, Sec. 35-3) (Ord. No. 2426, 2640)
(A) A breakaway wall shall have a safe design loading resistance of not less than 10 and no more than 20 pounds per square foot.
(B) Use of breakaway walls must be certified by a registered engineer or architect and shall meet the following conditions:
(1) Breakaway wall collapse shall result from a water load less than that which would occur during the base flood; and
(2) The elevated portion of the building shall not incur any structural damage due to the effects of wind and water loads acting simultaneously in the event of the base flood.
(`64 Code, Sec. 35-4) (Ord. No. 2426, 2640)
(A) For mobile homes not within a mobile home park or mobile home subdivision, "start of construction" means the affixing of the mobile home to its permanent site.
(B) For mobile homes within mobile home parks or mobile home subdivisions, "start of construction" is the date on which the construction of facilities to serve the site on which the mobile home is to be affixed (including, at a minimum, the construction of streets, either final site grading or the pouring of concrete pads, and installation of utilities) is completed.
(`64 Code, Sec. 35-5) (Ord. No. 2426, 2640)
"Substantial improvement" means any reconstruction, rehabilitation, addition, or other proposed new development of a structure, the cost of which equals or exceeds 50% 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 actual repair work performed. The term does not, however, include either:
(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; or
(B) Any alteration of an historic structure, provided that the alteration will not preclude the structure's continued designation as an historic structure.
(`64 Code, Sec. 35-6) (Ord. No. 2426, 2640)
A structure or other development without an elevation certificate, other certifications, or other evidence of compliance required in this chapter is presumed to be in violation until such time as that documentation is provided to the city.
(`64 Code, Sec. 35-7) (Ord. No. 2426, 2640)
This chapter shall apply to all areas of special flood hazards within the jurisdiction of the city.
(`64 Code, Sec. 35-8) (Ord. No. 2426, 2640)
(A) The areas of special flood hazard identified by the Federal Emergency Management Agency of the Federal Insurance Administration in a scientific and engineering report entitled "The Flood Insurance Study for the City of Oxnard," dated October 15, 1985, and accompanying flood insurance rate maps and all subsequent revisions are hereby adopted by reference and declared to be a part of this chapter.
(B) The flood insurance study is the minimum area of applicability of this chapter and may be supplemented by studies for other areas that allow implementation of this chapter and that are recommended to the city council by the floodplain administrator.
(C) The flood insurance study is on file at City Hall, 305 West Third Street, Oxnard, California.
(`64 Code, Sec. 35-9) (Ord. No. 2426, 2640)
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. Violations of the provisions of this chapter by failure to comply with any of its requirements (including violations of conditions and safeguards established in connection with conditions) shall constitute a misdemeanor. Nothing herein shall prevent the city from taking such lawful action as is necessary to prevent or remedy any violation.
(`64 Code, Sec. 35-10) (Ord. No. 2426, 2640)
This chapter is not intended to repeal, abrogate, or impair any existing easements, covenants, or deed restrictions. However, where this chapter and another ordinance, easement, covenant, or deed restriction conflict or overlap, whichever imposes the more stringent restrictions shall prevail.
(`64 Code, Sec. 35-11) (Ord. No. 2426, 2640)
In the interpretation and application of this chapter, all provisions shall be:
(A) Considered as minimum requirements;
(B) Liberally construed in favor of the city; and
(C) Deemed neither to limit nor repeal any other powers granted under State statutes.
(`64 Code, Sec. 35-12) (Ord. No. 2426, 2640)
(A) 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 manmade 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.
(B) This chapter shall not create liability on the part of the city, any officer or employee thereof, or the Federal Insurance Administration, for any flood damages that result from reliance on this chapter or any administrative decision lawfully made hereunder.
(`64 Code, Sec. 35-13) (Ord. No. 2426, 2640)
The chapter and the various parts thereof are hereby declared to be severable. Should any section of this chapter be declared by the courts to be unconstitutional or invalid, such decision shall not affect the validity of the chapter as a whole, or any portion thereof other than the section so declared to be unconstitutional or invalid.
(Ord. No. 2783)
ARTICLE II. ADMINISTRATION
The city engineer is hereby appointed as floodplain administrator to administer and implement this chapter by granting or denying development permit applications in accordance with its provisions.
(`64 Code, Sec. 35-15) (Ord. No. 2426, 2640)
Duties of the floodplain administrator shall include, but not be limited to the following:
(A) Permit review -
(1) Review all development permits to determine that the permit requirements of this chapter have been satisfied;
(2) Determine that all other required State and federal permits have been obtained;
(3) Determine that the site is reasonably safe from flooding; and
(4) Determine that the proposed development does not adversely affect the carrying capacity of the areas where base flood elevations have been determined but a floodway has not been designated. For purposes of this chapter, "adversely affects" means that the cumulative effect of the proposed development when combined with all other existing and anticipated development will increase the water surface elevation of the base flood more than one foot at any point.
(B) Use of other base flood data - When base flood elevation data has not been provided in accordance with section 18-9, the floodplain administrator shall obtain, review, and reasonably utilize any base flood elevation and floodway data available from a federal or State agency, or other source, in order to administer section 18-3.
(C) If no base flood elevation data is available from a federal or State agency or other source, the floodplain administrator shall obtain a base flood elevation using one of the following methods from the FEMA publication "Managing Floodplain Development in Approximately Zone A Areas - A Guide for Obtaining and Developing Base (100-year) Flood Elevations," dated July 1995:
(1) Simplified method:
(a) Obtain a 100-year or base flood discharge using the appropriate regression equation found in a U.S. Geological Survey publication, or the discharge-drainage area method; and
(b) Obtain a base flood elevation using the Quick-2 computer program developed by FEMA; or
(2) Detailed method:
(a) Obtain a 100-year or base flood discharge using the U.S. Army Corps of Engineers' HEC-HMS computer program; and
(b) Obtain a base flood elevation using the U.S. Army Corps of Engineers' HEC.RAS computer program.
(D) Notification of other agencies.
(1) In alteration or relocation of a watercourse, the floodplain administrator shall:
(a) Notify adjacent communities and the California Department of Water Resources prior to alteration or relocation;
(b) Submit evidence of such notification to the Federal Emergency Management Agency; and
(c) Ensure that the flood carrying capacity within the altered or relocated portion of said watercourse is maintained.
(2) When base flood elevations change due to physical alterations, the floodplain administrator shall:
(a) Within six months of information becoming available or project completion, whichever comes first, the floodplain administrator shall submit or assure that the permit applicant submits technical or scientific data to FEMA for a Letter of Map Revision (LOMR).
(b) All LOMR’s for flood control projects are approved prior to the issuance of building permits. Building permits must not be issued based on Conditional Letters of Map Revision (CLOMR’s). Approved CLOMR’s allow construction of the proposed flood control project and land preparation as specified in the “start of construction” definition.
(c) Such submissions are necessary so that upon confirmation of those physical changes affecting flooding conditions, risk premium rates and floodplain management requirements are based on current data.
(3) The floodplain administrator shall notify FEMA in writing whenever the corporate boundaries have been modified by annexation or other means and include a copy of a map of the community clearly delineating the new corporate limits.
(E) The floodplain administrator shall obtain and maintain for public inspection and make available, as needed, the following:
(1) Certification required by section 18-35(C)(1) (lowest flood elevations);
(2) Certification required by section 18-35(C)(3) (elevation or flood proofing of nonresidential structures);
(3) Certification required by sections 18-35(C)(4) (wet flood proofing standard);
(4) Certification of elevation required by section 18-37 (subdivision standards);
(5) Certification of elevation required by section 18-37 (subdivision standards);
(6) Certification required by section 18-38 (floodway encroachments);
(7) Information required by section 18-39(F) (coastal construction standards).
(F) The floodplain administrator shall make interpretations where needed, as to the exact location of the boundaries of the areas of special flood hazard. Where there appears to be a conflict between a mapped boundary and actual field conditions, the floodplain administrator shall use grade and base flood elevations to determine the boundaries of the special flood hazard area. The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as provided in section 18-26.
(G) The floodplain administrator shall take action to remedy violations of this chapter as specified in section 18-10.
(`64 Code, Sec. 35-16) (Ord. No. 2426, 2640, 2783)
ARTICLE III. PERMIT, APPEAL AND VARIANCE PROCEDURES
(A) A development permit shall be obtained before construction or development begins within any area of special flood hazard (as defined in sections 18-2 and 18-9). Application for a development permit shall be made on forms furnished by the floodplain administrator and may include, but not be limited to, plans in duplicate drawn to scale showing the nature, location, dimensions, and elevation of the area in question; existing or proposed structures; fill; storage of materials; drainage facilities; and the location of the foregoing.
(B) The application shall specifically require the following information:
(1) Site plan, including, but not limited to:
(a) For all proposed structures, spot ground elevations at building corners and 20-foot or smaller intervals along the foundation footprint, or one foot contour elevations throughout the building site;
(b) Proposed locations of water supply, sanitary sewer, and utilities;
(c) If available, the base flood elevation from the Flood Insurance Study and/or Flood Insurance Rate Map; and
(d) If applicable, the location of the regulatory floodway.
(2) Foundation design detail, including but not limited to:
(a) Proposed elevation in relation to mean sea level, of the lowest floor (including basement) of all structures;
(c) For foundations placed on fill, the location and height of fill, and compaction requirements (compacted to 95% using the Standard Proctor Test method).
(3) Proposed elevation in relation to mean sea level to which any nonresidential structure will be flood proofed, as required in subsection 18-35(C)(2) and FEMA Technical Bulletin TB 3-93.
(4) All appropriate certifications listed in subsection 18-21(E); and
(5) Description of the extent to which any watercourse will be altered or relocated as a result of the proposed development.
(`64 Code, Sec. 35-17) (Ord. No. 2426, 2640)
(A) The city council is designated as the appeal board and shall hear and decide appeals and requests for variances from the requirements of this chapter.
(B) The city council shall hear and decide appeals when the applicant alleges that the floodplain administrator made an error in any requirement, decision, or determination in the enforcement or administration of this chapter.
(C) In deciding such appeals, the city council shall consider all technical evaluations and relevant factors, and standards specified in other sections of this chapter, including the following factors:
(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 current and future owners of the property;
(4) The importance of the services provided by the proposed facility to the city;
(5) The necessity to the facility of a waterfront location, where applicable;
(6) The availability of alternative locations for the proposed use that are not subject to flooding or erosion damage;
(7) The compatibility of the proposed use with existing and anticipated development;
(8) The relationship of the proposed use to the comprehensive plan and floodplain management program for that area;
(9) The safety of access to the property in time of flood for ordinary and emergency vehicles;
(10) The expected heights, velocity, duration, rate of rise, and sediment transport of the flood waters expected at the site; and
(11) 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) Upon consideration of the factors of subsection (C) above and the purposes of this chapter, the city council may attach such conditions to appeals and variances granted.
(E) Any applicant to whom a variance is granted shall be given written notice signed by the floodplain administrator that:
(1) The issuance of a variance to construct a structure below the base flood level will result in increased premium rates for flood insurance up to amounts as high as $25 for $100 of insurance coverage; and
(2) Such construction below the base flood level increases risks to life and property.
(F) The floodplain administrator shall record a copy of the notice in the Office of Ventura County Recorder in such manner that the notice appears in the chain of the title of the affected parcel of land.
(G) The floodplain administrator shall maintain a record of all variance decisions, including the justification for their issuance, and report variances granted in the biennial report submitted to the Federal Insurance Administration, Federal Emergency Management Agency.
(`64 Code, Sec. 35-19) (Ord. No. 2426, 2640)
(A) The variance criteria set forth in this section are based on the general principle of zoning laws that variances pertain to a piece of property and are not personal in nature. A variance may be granted for a parcel of property with physical characteristics so unusual that complying with the requirements of this chapter would create an exceptional hardship to the property owner or surrounding property owners. The characteristics must be unique to the property and not be shared by adjacent parcels. The unique characteristics must pertain to the land itself, not to the structure, its inhabitants or the property owners.
(B) It is the duty of the city to help protect its citizens from flooding. This need is so compelling and the implications of the cost of insuring a structure built below flood level are so serious that variances from the flood elevation or from other requirements in the flood ordinance are quite rare. The long-term goal of preventing and reducing flood loss and damage can be met only if variances are strictly limited. Therefore, the variance guidelines provided in this chapter are detailed and contain multiple provisions that must be met before a variance can be properly granted. The guidelines are designed to identify situations in which alternatives other than a variance are more appropriate.
(C) Generally, variances may be issued for new construction, substantial improvement, and other proposed new developments 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 that the procedures of Articles 2 and 4 of this chapter have been fully considered. As the lot size increases beyond one-half acre, the technical justification required for issuing the variance increases.
(D) Variances may be issued for the repair or rehabilitation of "historic structures" upon a determination that the proposed repair or rehabilitation will not preclude the structure's continued designation as a historic structure and the variance is the minimum necessary to preserve the historic character and design of the structure.
(E) Variances shall not be issued within any mapped regulatory floodway if any increase in flood levels during the base flood discharge would result.
(F) Variances shall only be issued upon a determination that the variance is the "minimum necessary" considering the flood hazard, to afford relief. "Minimum necessary" means to afford relief with a minimum of deviation from the requirements of this chapter. For example, in the case of variances from an elevation requirement, the city council need not grant permission for the applicant to build at grade, or even to whatever elevation the applicant proposes, but only to that elevation which the city council finds will both provide relief and preserve the integrity of this chapter.
(G) Variances shall be issued only upon a:
(1) Showing of good and sufficient cause;
(2) Determination that failure to grant the variance would result in exceptional hardship (as defined in section 18-2 of this chapter) to the applicant; and
(3) Determination that the granting of a variance will not result in increased flood heights, additional threats to public safety, extraordinary public expense, create a nuisance (as defined in section 18-2 of this chapter), cause fraud or victimization (as defined in section 18-2 of this chapter) of the public, or conflict with other city ordinances.
(H) Variances may be issued for new construction, substantial improvement, and other proposed new development necessary for the conduct of a functionally dependent use provided that the provisions of subsections 18-27(C) through 18-27(H) are satisfied, that the structure or other development is protected by methods that minimize flood damages during the base flood, and that the variance does not result in additional threats to public safety or create a public nuisance.
(`64 Code, Sec. 35-20) (Ord. No. 2426, 2640)
ARTICLE IV. PROVISIONS FOR FLOOD HAZARD REDUCTION
In all areas of special flood hazards, the following standards apply:
(A) Anchoring -
(1) All new construction and substantial improvements shall be adequately anchored to prevent flotation, collapse or lateral movement of the structure resulting from hydrodynamic or hydrostatic loads, including the effects of buoyancy.
(2) All manufactured homes shall meet the anchoring standards of this chapter.
(B) Construction materials and methods -
(1) All new construction and substantial improvements shall be constructed with flood resistant materials as specified in FEMA Technical Bulletin TB 2-93 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) 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; and
(4) Within Zone AH or AO, so that there are adequate drainage paths around structures on slopes to guide flood waters around and away from proposed structures.
(C) Elevation and flood proofing. (See section 18-2 definitions for "basement," "lowest floor," "new construction," "substantial damage," and "substantial improvement.")
(1) The lowest floor, including basement, of a residential construction, new or substantial improvement, shall:
(a) In a Zone AO, be elevated above the highest adjacent grade to a height equal to or exceeding the depth number specified in feet on the FIRM, or elevated at least two feet above the highest adjacent grade if no depth number is specified. In Zone AO without velocity, the lowest floor shall be elevated above the highest adjacent grade to a height exceeding the depth number specified in feet on the FIRM by at least two feet, or elevated at least four feet above the highest adjacent grade if no depth number is specified.
(b) In a Zone A, be elevated at least two feet above the base flood elevation. Said base flood elevation shall be determined by one of the methods in section 18-21(B).
(c) In all other zones, be elevated at least two feet above the base flood elevation. Upon the completion of the structure, the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor, and verified by a city building inspector to be properly elevated. Such certification and verification shall be filed with the floodplain administrator.
(2) Nonresidential construction, new or substantial improvement, shall either be elevated to conform with subsection 18-35(C)(1) or, together with attendant utility and sanitary facilities:
(a) Be flood proofed below the elevation recommended under section 18-35(C)(1) so that the structure is watertight with walls substantially impermeable to the passage of water;
(b) Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and
(c) Be certified by a registered professional engineer or architect that the standards of this subsection 18-35(C)(2) are satisfied. Such certification shall be filed with the floodplain administrator.
(3) All new construction and substantial improvement with fully enclosed areas below the lowest floor (excluding basements) that are usable solely for parking of vehicles, building access or storage, and which are subject to flooding, shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwater. Designs for meeting this requirement shall follow the guidelines in FEMA Technical Bulletins TB 1-93 and TB 7-93, and must exceed the following minimum criteria:
(a) Have 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. The bottom of all openings shall be no higher than one foot 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 floodwater; or
(b) Be certified by a registered professional engineer or architect.
(4) Manufactured homes shall also meet the standards in this section.
(`64 Code, Sec. 35-21) (Ord. No. 2426, 2640)
(A) All new and replacement water supply and sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the system and discharge from systems into flood waters.
(B) All final subdivision plans will provide the elevation of proposed structure(s) and pads. If the site is filled above the base flood, the final pad elevation shall be certified by a registered professional engineer or surveyor and provided to the floodplain administrator.
(C) On-site waste disposal systems shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage.
(D) All subdivisions shall locate and construct public utilities and facilities such as sewer, gas, electrical, and water systems to minimize flood damage.
(E) All subdivision proposals shall provide adequate drainage to reduce exposure to flood hazards.
(`64 Code, Sec. 35-22) (Ord. No. 2426, 2640)
(A) All preliminary subdivision proposals shall identify the flood hazard area and the elevation of the base flood.
(B) All final subdivision plans will provide the elevation of proposed structure(s) and pads. If the site is filled above the base flood, the final pad elevation shall be certified by a registered professional engineer or surveyor and provided to the floodplain administrator.
(C) All subdivisions shall be designed to minimize flood damage.
(D) All subdivisions shall locate and construct public utilities and facilities such as sewer, gas, electrical and water systems to minimize flood damage.
(E) All subdivisions shall provide adequate drainage to reduce exposure to flood hazards.
(`64 Code, Sec. 35-23) (Ord. No. 2426, 2640)
(A) All manufactured homes that are placed or substantially improved, on sites located:
(1) Outside of a manufactured home park or subdivision;
(2) In a new manufactured home park or subdivision;
(3) In an expansion to an existing manufactured home park or subdivision; or
(4) In an existing manufactured home park or subdivision upon which a manufactured home has incurred “substantial damage” as a result of a flood shall:
(a) Within Zones A1-30, AH and AE on the community’s Flood Insurance Rate Map, be elevated on a permanent foundation such that the lowest floor of the manufactured home is elevated to or above the base flood elevation and be securely fastened to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.
(b) Within Zones V1-30, V and VE on the community’s Flood Insurance Rate Map, meet the requirements of Section 18-39.
(B) All manufactured homes to be placed or substantially improved on sites in an existing manufactured home park or subdivision within Zones A1-30, AH, AE, V1-30, V and VE on the community’s Flood Insurance Rate Map that are not subject to the provisions of section 18-37.1(A) will be securely fastened to an adequately anchored foundation system to resist flotation, collapse, and lateral movement, and be elevated so that either the:
(1) Lowest floor of the manufactured home is at or above the base flood elevation; or
(2) Manufactured home chassis is supported by reinforced pies or other foundation elements of at least equivalent strength that are not less than 36 inches in height above ground.
(C) Upon the completion of the structure, the elevation of the lowest floor including basement shall be certified by a registered civil engineer or licensed land surveyor, and verified by the community building inspector to be properly elevated. Such certification and verification shall be provided to the floodplain administrator.
(Ord. No. 2783)
(A) All recreational vehicles placed in Zones A1-30, AH, AE, V1-30 and VE will either:
(1) Be on the site for fewer than 180 consecutive days; or
(2) Be fully licensed and ready for highway use. A recreational vehicle is ready for highway uses if it is on its wheels or jacking system, is attached to the site only by quick disconnect type utilities and security devices, and has no permanently attached additions; or
(Ord. No. 2783)
(A) Located within areas of special flood hazard are areas designated as floodways.
(B) Because the floodway is an extremely hazardous area due to the velocity of flood waters that carry debris, potential projectiles, and erosion potential, the floodplain administrator shall:
(1) Prohibit encroachments, including fill, new construction, substantial improvements, and other development unless certification by a registered professional engineer or architect is provided demonstrating that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge.
(2) If the requirements of subsection (1) above are satisfied, ensure that all new construction and substantial improvements shall comply with all other applicable flood hazard reduction provisions.
(`64 Code, Sec. 35-25) (Ord. No. 2426, 2640)
Within coastal high hazard areas designated in "The Flood Insurance Study for the City of Oxnard," the following standards shall apply:
(A) All new construction and substantial improvements shall be elevated on five adequately anchored pilings or columns and securely anchored to such pilings or columns so that the lowest horizontal portion of the structural members of the lowest floor (excluding the pilings or columns) is elevated to or above the base flood level. The pile or column foundation and structure attached thereto shall be anchored to resist floating, collapse, and lateral movement due to the effects of wind and water loads acting simultaneously on all building components. 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.
(B) All new construction shall be located on the landward side of the reach of mean high tide.
(C) All new construction and substantial improvements shall have the space below the lowest floor free of obstructions or constructed with breakaway walls. Such temporarily enclosed space shall not be used for human habitation.
(D) Fill shall not be used for structural support of buildings.
(E) Manmade alteration of sand dunes that would increase potential flood damage is prohibited.
(F) The floodplain administrator shall obtain and maintain the following records:
(1) Certification by a registered engineer or architect that a proposed structure complies with this section; and
(2) The elevation (in relation to mean sea level) of the bottom of the lowest structural member of the lowest floor (excluding pilings or columns) of all new and substantially improved structures, and whether such structures contain a basement.
(`64 Code, Sec. 35-26) (Ord. No. 2426, 2640)
(A) The floodplain administrator shall require permits for proposed construction and other development within all flood-related erosion-prone areas.
(B) The floodplain administrator shall review permit applications to determine whether the proposed site alterations and improvements will be reasonably safe from flood-related erosion and will not cause flood-related erosion hazards or otherwise aggravate the existing hazard.
(C) If a proposed improvement is found to be in the path of flood-related erosion or would increase the erosion hazard, the floodplain administrator shall require that such improvement be relocated or adequate protective measures be taken to avoid aggravating the existing erosion hazard.
(D) Within Zone E on the Flood Insurance Rate Map, a setback is required for all new development from the ocean, lake, bay, riverfront or other body of water to create a safety buffer consisting of a natural vegetative or contour strip. This buffer shall be designated according to the flood-related erosion hazard and erosion rate, in relation to the anticipated "useful life" of structures, and depending upon the geologic, hydrologic, topographic and climatic characteristics of the land. The buffer may be used for suitable open space purposes, such as for agricultural, forestry, outdoor recreation and wildlife habitat areas, and for other activities using temporary and portable structures only.
(Ord. No. 2640)