Chapter 18.90
FLOODPLAIN DISTRICT (FP)
Sections:
18.90.070 Critical facilities.
18.90.080 Warning and disclaimer of liability.
18.90.090 Abrogation and severability.
18.90.100 Special administrative provisions for the FP zone.
18.90.110 Development application procedures.
18.90.120 Appeal and variances.
18.90.130 Violation and penalties.
Prior legislation: Ords. 810 and 841; Code 2000 §§ 11.20.91 – 11.20.93.
18.90.010 Purpose.
(A) The city of Cornelius has the primary responsibility for planning, adoption, and enforcement of land use regulations to accomplish proper management of special flood hazard areas within the city limits.
(B) It is the purpose of the FP zone to promote the public health, safety and general welfare and to minimize public and private losses or damages 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 public;
(4) Minimize damage to public facilities and utilities such as water and gas mains, electric, telephone and sewer lines, streets and bridges located in areas of special flood hazards;
(5) Help maintain a stable tax base by providing for the sound use and development of areas of special flood hazard;
(6) Ensure that potential buyers are notified that property is in an area of special flood hazard;
(7) Ensure that those who occupy the areas of special flood hazard assume responsibility for their actions;
(8) Maintain the functions and values associated with special flood hazard areas which reduce the risk of flooding.
(C) Basis for Establishing the Areas of Special Flood Hazard. The special flood hazard areas are identified by the Federal Insurance Administration in a scientific and engineering report entitled “The Flood Insurance Study for Washington County, Oregon and Incorporated Areas,” Volumes 1 through 3, dated November 4, 2016 (Flood Insurance Study Number 41067CV001A, 41067CV002A and 41067CV003A), with accompanying flood insurance rate maps (FIRM) (Map Number 41067C0314E, 41067C0318E and 41067C0319E, dated November 4, 2016), are hereby adopted by reference and declared to be a part of this chapter. The flood insurance study and the FIRM are on file at the city of Cornelius community development department located at 1300 S. Kodiak Circle, Cornelius, OR 97113. The best available information for flood hazard area identification as outlined in this section shall be the basis for regulation. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.020 Definitions.
Unless specifically defined below or within Chapter 18.195 CMC, 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.
“Addition” means an alteration to an existing structure that results in any increase in its ground floor area.
“Appeal” means a request for a review of the 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 to three feet; a clearly defined channel does not exist; the path of flooding is unpredictable and indeterminate; and velocity flow may be evident. AO is characterized as sheet flow.
“Base flood” means flood having a one percent chance of being equaled or exceeded in any given year. Also referred to as the “100-year flood.” Designation on maps always includes the letters A, AE, AH, AO, or AR.
“Basement” means any area of a building having its floor subgrade (below ground level) on all sides.
“Conditional letter of map revision (CLOMR)” means letter from FEMA commenting on whether a proposed project, if built as proposed, would meet the minimum National Flood Insurance Program standards for proposed hydrology changes. If the project, built as proposed, revises the flood insurance rate map and/or flood insurance study, a letter of map revision (LOMR) is required to be submitted no later than six months after project completion.
“Critical facility” means a facility for which even a slight chance of flooding might be too great. Critical facilities include, but are not limited to, schools, nursing homes, hospitals, police, fire and emergency response installations, installations which produce, use or store hazardous materials or hazardous waste.
“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, drilling operations, or the storage of equipment or materials located within a special flood hazard area.
“Elevated building” means, for insurance purposes, a nonbasement building which has its lowest elevated floor raised above ground level by foundation walls, shear walls, post, piers, pilings, or columns.
“Enhancement” means the process of improving upon the natural functions and/or values of an area or feature which has been degraded by human activity.
“Fill” means any material such as, but not limited to, sand, gravel, soil, rock or gravel that is placed on land including existing and natural floodplains, or in waterways, for the purposes of development or redevelopment.
“Flood” or “flooding” means a general and temporary condition of partial or complete inundation of normally dry land areas from:
(1) The overflow of inland waters; and/or
(2) 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 Emergency Management Agency has delineated both the special flood hazard areas and 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.
“Floodplain” means any land area susceptible to being inundated by water from the sources specified in the “flood(ing)” definition.
“Floodplain management regulations” means the provisions of this chapter in addition to the development and zoning code, building codes, health regulations, and other applications of police power. The term describes such state or local regulations, in any combination thereof, which provide standards for the purpose of flood damage prevention and reduction.
“Floodway, regulatory” 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 elevation more than one foot. The regulatory floodway is delineated by the Federal Emergency Management Agency on the flood insurance study and flood insurance rate map.
“Highest adjacent grade” means the highest natural elevation of the ground surface prior to construction next to the proposed walls of a structure.
“Hydrodynamic loads” means loads induced on buildings or structures by the flow of flood water moving at moderate or high velocity around the buildings or structures or parts thereof, above ground level when openings or conduits exist which allow the free flow of flood waters. Hydrodynamic loads are basically of the lateral type and relate to direct impact loads by the moving mass of water, and to drag forces as the water flows around the obstruction.
“Hydrostatic loads” means loads caused by water either above or below the ground surface, free or confined, which is either stagnant or moves at very low velocities, of up to five feet per second. These loads are equal to the product of the water pressure times the surface area on which the water acts. The pressure at any point is equal to the product of the unit weight of water (62.5 pounds per cubic foot) multiplied by the height of water above that point or by the height to which confined water would rise if free to do so.
“Letter of map change (LOMC)” means an official FEMA determination, by letter, to amend or revise effective flood insurance rate maps and/or flood insurance studies. LOMCs are issued in the following categories:
(1) “Letter of map amendment (LOMA)” means an amendment to the flood insurance rate maps based on technical data showing that an existing structure, parcel of land, or portion of a parcel of land that has not been elevated by fill (natural grade) was inadvertently included in the special flood hazard area because of an area of naturally high ground above the base flood.
(2) “Letter of map revision (LOMR)” means:
(a) LOMR-F (letter of map revision based on fill) is a letter from FEMA stating that an existing structure or parcel of land that has been elevated by fill would not be inundated by the base flood.
(b) A LOMR revises the current flood insurance rate map and/or flood insurance study to show changes to the floodplains, floodways or flood elevations. LOMRs are generally based on manmade alterations that affect the hydrologic or hydraulic characteristics of a flooding source and thus result in modification to the existing regulatory floodway, the effective base flood elevation, or the special flood hazard area. A conditional letter of map revision (CLOMR) may be approved by FEMA prior to issuing a permit to start a project if the project has a potential to affect the special flood hazard area.
“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 dwelling” means 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 dwelling” does not include a “recreational vehicle.”
“Manufactured home park or subdivision” means a parcel (or contiguous parcels) of land divided into two or more manufactured home lots for rent or sale.
“Mechanical equipment” means electrical, heating, ventilation, plumbing, and air conditioning equipment, storage tanks and other service facilities.
“Mitigation” means the reduction of adverse effects of a proposed project by considering, in the following order:
(1) Avoiding the impact altogether by not taking a certain action or parts of an action;
(2) Minimizing impacts by limiting the degree or magnitude of the action and its implementation;
(3) Rectifying the impact by repairing, rehabilitating, or restoring the affected environment;
(4) Reducing or eliminating the impact over time by preservation and maintenance operations during the life of the action by monitoring and taking appropriate measures;
(5) Mitigating for the impact by replacing or providing comparable substitute floodplain areas.
“New construction” means structures for which the “start of construction” commenced on or after the effective date of the ordinance codified in this chapter.
“Permanent foundation” means a natural or manufactured support system to which a structure is anchored or attached. A “permanent foundation” is capable of resisting flood forces and may include posts, piles, poured concrete or reinforced block walls, properly compacted fill, or other systems of comparable flood resistivity and strength.
“Reconstruction” means the repair of a structure damaged by any cause (not limited to flooding) without increasing the floor area of the structure.
“Recreational vehicle” means 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.
“Rehabilitation” means any improvements and repairs made to the interior and exterior of an existing structure that do not result in an increase in the ground floor area of the structure. Examples include remodeling a kitchen, gutting a structure and redoing the interior, or adding a second story.
“Restoration” means the process of returning a disturbed or altered area or feature to a previously existing natural condition. Restoration activities reestablish the ecological structure, function, and/or diversity to that which occurred prior to impacts caused by human activity.
“Special flood hazard area (SFHA)” means zones on flood insurance rate maps that depict the land in the floodplain within a community that is subject to a one percent or greater chance of flooding in any given year. Special flood hazard area is synonymous with “area of special flood hazard.” Special flood hazard areas on flood insurance rate maps are always designated as zones A, AE, AH, AO, or AR.
“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 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, for the purposes of this section, a walled and roofed building, a modular or temporary building, or a gas or liquid storage tank 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 50 percent of the market value of the structure before the damage occurred.
“Substantial improvement” means any repair, reconstruction, rehabilitation, addition, or improvement of a structure, the cost of which equals or exceeds 50 percent of the market value of the structure either: (1) before the improvement or repair is commenced; or (2) if the structure has been damaged and is being restored, before the damage occurred. For the purposes of this definition, “substantial improvement” is considered to occur when the first alteration of any wall, ceiling, floor, or other structural part of the building commences, whether or not that alteration affects the external dimensions of the structure. The term does not include improvements to a structure to correct violations identified by the city’s building official or alterations to a structure on the National Register of Historic Places or a comparable Oregon register or inventory.
“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.
“Water dependent” means a structure for commerce or industry which cannot exist in any other location and is dependent on the water by reason of the intrinsic nature of its operations.
“Water surface elevation” means heights, in relation to a specific datum, of floods of various magnitudes and frequencies in the floodplains. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.030 General standards.
In all special flood hazard areas the following standards are required:
(A) Anchoring.
(1) All new construction and substantial improvements shall be anchored to prevent flotation, collapse or lateral movement of the structure.
(2) All manufactured dwellings must likewise be anchored to prevent flotation, collapse or lateral movement, and shall be installed using methods and practices that minimize flood damage. Anchoring methods may include, but are not limited to, use of over-the-top or frame ties to ground anchors (See FEMA’s “Manufactured Home Installation in Flood Hazard Areas” guidebook for techniques). A certificate signed by a registered architect or engineer which certifies that the anchoring system is in conformance with FEMA regulations shall be submitted prior to final inspection approval.
(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) Electrical, heating, ventilation, plumbing, and air-conditioning equipment and other service facilities shall be elevated to prevent water from entering or accumulating within the components during conditions of flooding. In flood zones A, AE, and AH such facilities shall be elevated three feet above base flood elevation. In flood zone AO, such facilities shall be elevated above the highest grade adjacent to the building, a minimum of one foot above the depth number specified on the FIRM (at least two feet above the highest adjacent grade if no depth number is specified).
(C) Utilities.
(1) All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood water into the system.
(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.
(3) On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding consistent with the Oregon Department of Environmental Quality.
(D) Subdivision and Partition Proposals.
(1) All subdivision and partition proposals governed by the development and zoning ordinance shall be consistent with the need to minimize flood damage.
(2) All subdivision and partition proposals governed by the development and zoning ordinance shall have public utilities and facilities such as sewer, gas, electrical, and water systems located and constructed to minimize flood damage.
(3) All subdivisions and partition proposals governed by the development and zoning ordinance shall have adequate drainage provided to reduce exposure to flood damage.
(4) All subdivision and partition proposals shall comply with all applicable Clean Water Services (CWS) standards with regard to development within flood area.
(5) Where base flood elevation data has not been provided or is not available from another authoritative source, it shall be generated for subdivision proposals and other proposed developments which contain at least 50 lots or five acres (whichever is less).
(E) Building and Manufactured Dwelling Permits. Where elevation data is not available either through the flood insurance study or from another authoritative source, applications for building permits and/or manufactured dwelling permits shall be reviewed to assure that proposed construction will be reasonably safe from flooding. The test of reasonableness is a local judgment and includes use of historical data, high water marks, photographs of past flooding, etc., where available. Failure to elevate at least two feet above grade in these zones may result in higher insurance rates.
(F) Recreational Vehicles. Recreational vehicles placed on sites within the special flood hazard area are required to:
(1) Be on the site for fewer than 180 consecutive days; and
(2) Be fully licensed and ready for highway use, 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
(3) Meet the requirements of subsection (D)(4) of this section and the elevation and anchoring requirements for manufactured homes.
(G) Accessory Structures. Relief from elevation or flood-proofing as required for structures in A, AE, AH or AO zones may be granted for accessory structures that are:
(1) Less than 200 square feet and do not exceed 12 feet in height;
(2) Not temperature controlled;
(3) Not used for human habitation and are used solely for parking of vehicles or storage of items having low damage potential when submerged;
(4) Not used to store toxic material, oil or gasoline, or any priority persistent pollutant identified by the Oregon Department of Environmental Quality unless confined in a tank installed in compliance with this chapter or stored at least one foot above base flood elevation;
(5) Constructed in accordance with anchoring and construction materials and methods standards in subsections (A)(1) through (D)(4) of this section;
(6) If in an A, AE or AH zone, constructed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this requirement must either be certified by a registered professional engineer or must meet or exceed the following requirements:
(a) 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;
(b) The bottom of all openings shall be no higher than one foot above grade;
(c) Openings may be equipped with screens, louvers, or other coverings or devices provided they permit the automatic entry and exit of floodwaters.
(7) The cost of flood insurance for a structure permitted to be built with a lowest floor elevation below the base flood elevation will be commensurate with the increased risk resulting from the reduced lowest floor elevation.
(H) AH Zone Drainage. Adequate drainage paths are required around structures on slopes to guide floodwaters around and away from proposed structures.
(I) Grading. Grading within the floodplain shall only occur between May 1st and September 1st of each year. Extension of the grading season in a particular year may only be granted by the community development director following a written request from a contractor, developer, or other project representative, and shall only be granted based on the following criteria:
(1) Precipitation is not anticipated within the requested extension period, based on predictions from the National Oceanic and Atmospheric Administration (NOAA) or another reputable weather service.
(2) The extension request is approved by Clean Water Services.
(3) The extension request will not violate any other applicable federal, state and local requirements, including but not limited to the Endangered Species Act. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.040 Specific standards.
In all special flood hazard areas where base flood data has been provided as set forth in CMC 18.90.010(C) or other base flood data are utilized, the following provisions are required:
(A) Residential Construction.
(1) New construction and substantial improvement of any residential structure shall have the lowest floor, including basement, at a minimum of two feet above base flood elevation.
(2) Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, or shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this requirement must either be certified by a registered professional engineer or must meet or exceed the following minimum criteria:
(a) 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;
(b) The bottom of all openings shall be no higher than one foot above grade;
(c) Openings may be equipped with screens, louvers, or other coverings or devices provided they permit the automatic entry and exit of floodwaters.
(B) Nonresidential Construction. New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall have either the lowest floor including basement elevated to two feet above the level of the base flood elevation or higher; or, together with attendant utility and sanitary facilities, shall:
(1) Be flood-proofed so that the portion of the structure that lies below the portion that is two feet or more above the base flood level 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) Be certified by a registered professional engineer or architect that the design and methods of construction are in compliance with accepted standards of practice for meeting provisions of this subsection based on their development and/or review of the structural design, specifications and plans. Such certifications shall be provided to the community development director;
(4) Nonresidential structures that are elevated, not flood-proofed, must meet the same standards for space below the lowest floor as described for residential construction in subsections (A)(1) and (2) of this section;
(5) Applicants flood-proofing nonresidential buildings shall be notified that flood insurance premiums will be based on rates that are one foot below the flood-proofed level (e.g., a building constructed to the base flood level will be rated as one foot below that level).
(C) Manufactured Dwellings. Manufactured dwellings to be placed or substantially improved within an A, AE, AH or AO zone shall be elevated so that:
(1) Manufactured dwellings supported on solid foundation walls shall be constructed with flood openings that comply with subsection (A)(2) of this section;
(2) The lowest floor of the manufactured home is elevated to a minimum of two feet above the base flood elevation; and
(3) The manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than 24 inches in height above grade and are securely anchored to an adequately designed foundation system to resist flotation, collapse and lateral movement in accordance with requirements of the Oregon Residential Specialty Code. Electrical crossover connections shall be a minimum of 12 inches above base flood elevation. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.050 Floodways.
Located within special flood hazard areas established in CMC 18.90.010(C) are areas designated as regulatory 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:
(A) Encroachments in the regulatory floodway including fill, new construction, substantial improvements, and other development are prohibited unless certification is provided by a professional registered civil engineer demonstrating through hydrologic and hydraulic analysis, performed in accordance with standard engineering practice, that such encroachment shall not result in any increase in flood levels during the occurrence of the base flood discharge.
(B) If subsection (A) of this section is satisfied, all new construction and substantial improvement shall comply with all applicable flood hazard reduction provisions of CMC 18.90.040.
(C) Projects for stream habitat restoration may be permitted in the floodway provided:
(1) The project qualifies for a Department of the Army, Portland District Regional General Permit for Stream Habitat Restoration (NWP-2007-1023); and
(2) The civil engineer shall, as a minimum, provide a feasibility analysis and certification that the project was designed to keep any rise in 100-year flood levels as close to zero as practically possible and that no structures will be impacted by a potential rise in flood elevation; and
(3) An agreement to monitor the project, correct problems, and ensure that flood carrying capacity remains unchanged is included as part of the local approval.
(D) Before a Regulatory Floodway Is Determined in an AE Zone. In areas where a regulatory floodway has not been designated, no new construction, substantial improvements or other development (including fill) shall occur within an AE zone designated on the community’s flood insurance rate map, unless it is demonstrated that the cumulative effect of the proposed development, when combined with all other existing and anticipated development, will not increase the water surface elevation of the base flood more than one foot at any point within the community.
(E) Temporary storage of goods and materials, not including hazardous materials, is allowed in the floodway for a period of less than 90 days within the dry season (June – October). [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.060 Shallow flooding.
Shallow flooding areas appear on FIRMs as AO zones with depth designations. The base flood depths in these zones range from one to three feet where a clearly defined channel does not exist, or where the path of flooding is unpredictable and where velocity flow may be evident. Such flooding is usually characterized as sheet flow. In these areas the following provisions apply:
(A) Require adequate drainage paths around structures on slopes to guide floodwaters around and away from proposed structures.
(B) Residential. New construction and substantial improvements of residential structures (including manufactured dwellings) within AO zones shall have the lowest floor (including basement) elevated above the highest grade adjacent to the building, a minimum of one foot above the depth number specified on the FIRM (at least two feet above the highest adjacent grade if no depth number is specified).
(C) Nonresidential. New construction and substantial improvements of nonresidential structures, including manufactured dwellings used for nonresidential purposes, within AO zones shall either:
(1) Have the lowest floor (including basement) elevated above the highest grade adjacent to the building, a minimum of one foot above the depth number specified on the FIRM (at least two feet above the highest adjacent grade if no depth number is specified); or
(2) Together with attendant utility and sanitary facilities, be completely flood-proofed to one foot above the depth number specified on the FIRM so that any space below that level 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. If this method is used, compliance shall be certified by a registered professional engineer or architect. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.070 Critical facilities.
Construction of new critical facilities shall be, to the extent possible, located outside the limits of the special flood hazard area (SFHA) (100-year floodplain). Construction of new critical facilities shall be permissible within the SFHA if no feasible alternative site is available. Critical facilities constructed within the SFHA shall have the lowest floor elevated three feet above BFE or to the height of the 500-year flood, whichever is higher. Access to and from the critical facility should also be protected to the height utilized above. Flood-proofing and sealing measures must be taken to ensure that toxic substances will not be displaced by or released into floodwaters. Access routes elevated to or above the level of the base flood elevation shall be provided to all critical facilities to the extent possible. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.080 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 manmade or natural causes. This chapter does not imply that land outside the areas of special flood hazard or uses permitted within such areas is guaranteed to be free from flooding or flood damages. This chapter shall not create liability on the part of the city of Cornelius, 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. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.090 Abrogation and severability.
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. If any section, clause, sentence, or phrase of this chapter is held to be invalid or unconstitutional by any court of competent jurisdiction, then said holding shall in no way effect the validity of the remaining portions of this chapter. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.100 Special administrative provisions for the FP zone.
(A) The community development director is hereby appointed to administer and implement the provisions of this floodplain (FP) overlay zone by granting or denying development permit applications in accordance with its provisions.
(B) Duties of the community development director shall include, but not be limited to:
(1) Review all development permit requests to assure that the requirements of this section have been satisfied and that all other necessary permits have been obtained from those federal, state or local governmental agencies from which prior approval is required.
(2) Review all other permit applications to determine compliance with this section.
(3) Review all development permits to determine if the proposed development is located in the floodway. If located in the floodway, assure that the encroachment provisions of CMC 18.90.050(A) are met.
(4) Notify adjacent communities and the Department of Land Conservation and Development prior to any alteration or relocation of a watercourse, and submit evidence of such notification to the Federal Insurance Administration.
(5) Require that maintenance is provided within the altered or relocated portion of said watercourse so that the flood carrying capability is not diminished.
(6) Provide base flood elevation and structure elevation requirements to the building official.
(7) Where base flood elevation data is provided through the flood insurance study or required within this section, obtain and record on an elevation certificate the actual elevation (in relation to a specific datum) of the lowest floor (including basement) of all new or substantially improved structures, and whether or not the structure contains a basement.
(8) For all new or substantially improved flood-proofed structures:
(a) Verify and record the actual elevation (in relation to a specific datum), and
(b) Maintain the flood-proofing certifications required in this section.
(9) Maintain for inspection in perpetuity the affidavits of certification required in this section. Affidavits of certification, such as elevation certificates, flood-proofing, floodway no-rise, etc., are required to be submitted by the permit applicant for elevations and structural requirements as specified in this section, both pre- and post-construction, utilizing forms provided for this purpose by FEMA. Elevations may be certified by a licensed surveyor or a registered professional architect or engineer. Structural requirements may be certified by a registered professional architect or engineer.
(10) Where interpretation is needed requiring the boundaries of the areas of special flood hazard, the community development director will make the necessary interpretation. The person contesting the ruling of the community development director shall be given a reasonable opportunity to appeal the ruling as provided in CMC 18.15.090 (Appeal Procedures).
(11) When base flood elevation has not been provided as set forth in this chapter, the community development director shall obtain, review, and reasonably utilize any base flood data and floodway available from federal, state, or other source in order to administer this chapter.
(C) All records pertaining to the provisions of this section shall be maintained in the city of Cornelius community development department and shall be available for public inspection.
(D) When a variance is granted, the community development director shall give written notice that the structure will be allowed to be built with the lowest floor elevation at or below base flood elevation, and that the cost of flood insurance will be commensurate with the increased risk resulting from the lowest floor elevation.
(E) Publicly owned open land recreation parks and accessory restroom facilities, where allowed in the underlying zone, shall be allowed in floodplain areas below the base flood elevation. The accessory restroom facilities shall be located outside of floodplain areas if possible. If it is not possible, the restroom structures shall be located:
(1) On the highest portion of the park grounds; and
(2) Be wet-flood-proofed; and
(3) Maintain riparian setbacks; and
(4) Adequate backflow valves shall be installed.
If the structure is located in a designated floodway, it shall conform to subsections (E)(1) through (4) of this section and shall be small enough and positioned so that it will not divert floodwaters. Any structure located within the regulatory floodway must have a floodway analysis to assure there is no rise in base flood elevation. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.110 Development application procedures.
A development permit shall be obtained before construction or development begins within any special flood hazard area. The permit shall be for all structures including manufactured dwellings, and for all development including fill and other development activities, as set forth in CMC 18.90.020.
(A) Application for a development permit shall be made on forms furnished by the community development director and shall include, but not necessarily be limited to: plans 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. The application shall also include required information listed in Chapter 18.100 CMC (Site Design Review), Chapter 18.95 CMC (Natural Resource Overlay), and the site development standards of the underlying zone and the applicable sections of this chapter, in addition to the following:
(1) Elevation in relation to a specific datum of the lowest floor, including basement, of all structures as documented on an elevation certificate;
(2) Elevation in relation to a specific datum to which any proposed structure will be flood-proofed as documented on an elevation certificate;
(3) If applicable, certification by a registered professional engineer or architect that the flood-proofing methods for any nonresidential structure meet the flood-proofing standards;
(4) Description of the extent to which any watercourse will be altered or relocated as a result of proposed development.
(B) Development Permit Review Criteria. In addition to the applicable site development standards of the base zone, Chapter 18.100 CMC (Site Design Review), and Chapter 18.95 CMC (Natural Resource Overlay) the following review and approval criteria shall apply to proposed fill (including grading or construction) located partially or wholly in the special flood hazard area:
(1) Fill is not proposed to be located within a regulatory floodway, wetland, riparian area, or other sensitive area regulated by the city of Cornelius or Clean Water Services.
(2) The fill is necessary for an approved use on the property.
(3) The fill is the minimum amount necessary to achieve the approved use.
(4) No feasible alternative upland locations exist on the property.
(5) The fill does not impede or alter drainage or the flow of floodwaters.
(6) All necessary permits have been received from those governmental agencies from which approval is required by federal or state law, including Section 404 of the Federal Water Pollution Control Act Amendments of 1972, 33 U.S.C. 1334.
Conditions of approval may require that if the fill is found to not meet the criterion in subsection (B)(5) of this section, the fill shall be removed or, where reasonable and practical, appropriate mitigation measures shall be required of the property owner. Such measures shall be verified by a certified engineer or hydrologist that the mitigation measures will not result in a net rise in floodwaters and be in coordination with applicable state, federal and local agencies, including the Oregon Department of Fish and Wildlife, Clean Water Services, the Division of State Lands, the Army Corps of Engineers, the National Marine Fisheries Service, and the U.S. Fish and Wildlife Service. Adequate notice of alteration of the floodplain will be given to the above-referenced agencies. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.120 Appeal and variances.
(A) An appeal of the ruling of the community development director regarding a requirement of this chapter may be made to the city of Cornelius planning commission pursuant to CMC 18.15.090 (Appeal Procedures).
(B) Variances shall be issued by the community development director on a case by case basis, subject to the following regulations:
(1) Variances shall not be issued by the community development director within any designated regulatory floodway if any increase in flood levels during the base flood discharge would result;
(2) Variances may be issued by the community development director 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;
(3) Variances shall only be issued by the community development director upon (a) a showing of good and sufficient cause, (b) a determination that failure to grant the variance would result in exceptional hardship to the applicant, and (c) 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, or conflict with existing local laws or ordinances;
(4) Variances shall only be issued upon a determination that the variance is the minimum necessary, considering the flood hazard, to afford relief;
(5) The community development director shall notify the applicant in writing that (a) 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 $25.00 for $100.00 of insurance coverage and (b) such construction below the base flood level increases risks to life and property. Such notification shall be maintained with a record of all variance actions as required in subsection (B)(6) of this section; and
(6) The community development director shall (a) maintain a record of all variance actions, including justification for their issuance, and (b) report such variances issued in its annual or biennial report submitted to the administrator.
(7) Variances may be issued by the community development director for new construction and substantial improvements and for other development necessary for the conduct of a functionally dependent use; provided, that (a) the criteria of subsections (B)(1) through (4) of this section are met, and (b) the structure or other development is protected by methods that minimize flood damages during the base flood and create no additional threats to public safety. [Ord. 2016-012 § 1 (Exh. A), 2016.]
18.90.130 Violation and penalties.
Violations of the provisions of this chapter, inclusive, by failure to comply with any of its requirements or prohibitions shall constitute a misdemeanor. Any person, firm or corporation who violates any of these provisions contained in this chapter, inclusive, shall, upon conviction, be fined not more than $10,000 for each violation and in addition shall pay all costs and expenses incurred by the city in the prosecution of said violation. Nothing herein contained shall prevent the city from taking such other lawful action as necessary to prevent or remedy any violation. [Ord. 2016-012 § 1 (Exh. A), 2016.]