A. It is the purpose of this chapter to promote the public health, safety and general welfare, and to minimize public and private losses due to flooding. In general, the city's flood hazard chapter is designed:

B. The city seeks to minimize or mitigate flood hazards by:

"Accessory structures" includes sheds or small detached garages (Note Section 17.84.140(I).)

"Applicant" refers to a person, organization, or agency applying for a development permit.

"Area of special flood hazard (SFHA)" means the land in the floodplain within a community subject to a one percent or greater chance of flooding in any given year. Designation of maps always includes the letter "A" (e.g., A, AE, AO). Federally regulated lending institutions require the purchase of flood insurance for residential and some nonresidential structures in these zones.

"Base flood" means the flood having a one percent chance of being equaled or exceeded in any given year. Also referred to as the "100-year" flood. Map designation always includes the letter "A" (e.g., A, AE, AO).

"Base flood elevation (BFE)" means the elevation of the base flood.

"Buoyant material" means a material which displaces a weight of water equal to its own weight; capable of floating.

"Development" means any manmade change to improved or unimproved real estate, including but not limited to buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations or storage of equipment or materials located within the area of special flood hazard.

"Development permit" refers to a document or building permit authorizing an applicant to commence construction/development activities in a special flood hazard area.

"Federal Emergency Management Agency (FEMA)" means the federal agency charged with implementing the National Flood Insurance Program. FEMA provides Flood Insurance Rate Maps with the accompanying Flood Insurance Study to the city of Scappoose.

"Fill" means the placement of any material on the land for the purpose of increasing its elevation in relation to that which exists. Fill materials include but are not limited to the following: soil, rock, concrete, etc.

"Flood" means a general and temporary condition of partial or complete inundation of normally dry land areas from:

"Flood insurance rate map (FIRM)" means the official map on which the Federal Insurance Administration has delineated both the areas of special flood hazards 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 Boundary-Floodway Map and the water surface elevation of the base flood.

"Floodway" means the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without increasing the water surface elevation more than one foot. Once established, nothing can be placed in the floodway that would cause any rise in base flood elevations. The city generally prohibits encroachments on designated floodways. (Section 17.84.180, Floodways). Floodways are depicted on the flood relationships diagram set out below.

"Floodway fringe" refers to those areas outside the floodway but within the one hundred-year floodplain. Note floodway relationships diagram set out above.

"Hazardous material" refers to a combustible, flammable, corrosive, explosive, toxic or radioactive substance which is potentially harmful to humans and the environment.

"Lowest floor" means the lowest portion of the lowest floor of the lowest enclosed area (including basement). An unfinished or flood-resistant enclosure, usable solely for parking 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 non-elevation design requirements of this chapter found at Section 17.84.140.

"Manufactured home" 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 home" does not include a "recreational vehicle." All manufactured homes in a SFHA shall be anchored to a permanent foundation pursuant to Section 17.84.140.

"New construction" means structures for which the "start of construction" commenced on or after the effective date of this chapter.

"Permanent foundation" means an approved structural support system that is capable of resisting flood forces. A building anchored to a permanent foundation is required to resist flotation, collapse, and lateral movement produced by a one hundred-year flood. A permanent foundation may include reinforced piers or block walls, posts, concrete walls, properly compacted fill or other systems of equivalent strength. Dry stacked concrete blocks do not constitute a reinforced pier.

"Public works projects" refers to projects that are necessary to enhance or maintain general public welfare. Such projects may include, but are not limited to, flood control structures, public buildings, city infrastructures, utilities, parks and projects associated with resource protection.

"SFHA." See "Special flood hazard area."

"Recreational Vehicle" means a vehicle which is (a) built on a single chassis; (b) 400 square feet or less when measured at the largest horizontal projection; (c) designed to be self-propelled or permanently towable by a light duty truck; and (d) designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel, or seasonal use.

"Special flood hazard area (SFHA)" refers to areas that are subject to a one hundred-year flood. They are depicted on Flood Insurance Rate Maps by the letter "A." In Scappoose, this would include Zone A, AE and AO. See "Zone designations."

"Special land use permit" refers to a document authorizing an applicant to store or stockpile buoyant or hazardous materials in a special flood hazard area. Requires planning commission approval.

"Start of construction" includes substantial improvement, and means the date the development permit was issued, provided the actual start of construction, repair, reconstruction, placement or other improvement was within one hundred eighty 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 or filling; nor does it include the installation of streets and/or walkways; nor does it include excavation for a basement, footings, piers or foundation 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" is a term that, for floodplain management purposes, means a walled and roofed building. The term also includes manufactured homes, and gas and liquid storage tanks that are principally above ground.

"Substantial damage" means damage of any origin sustained by a structure whereby the cost of restoring the structure to its before-damaged condition would equal or exceed fifty percent of its market value before the damage occurred.

"Substantial improvement" means any repair, rehabilitation, addition, reconstruction or other improvement of a structure, that includes the cumulative value of all building permits, and the cost of which equals or exceeds fifty percent of the market value of the structure either before the improvement or repair is started, or 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. This 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 a structure listed on the National Register of Historic Places or a State Inventory of Historic Places, provided that the alteration will not preclude the structure's continued designation as a "historic structure." Zone designations:

A. This chapter shall apply to all special flood hazard areas (Zones A, AE, AO) within the jurisdiction of the city.

B. The areas of special flood hazard identified by the Federal Insurance Administration in a scientific and engineering report entitled the "Flood Insurance Study for Columbia County, Oregon and Incorporated Areas," effective November 26, 2010, with accompanying Flood Insurance Rate Maps, is adopted by reference and declared to be a part of this chapter. The Flood Insurance Study is on file at the Planning Department.

C. All new construction and substantial improvements shall be constructed with materials and utilize equipment resistant to flood damage.

D. All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.

E. Electrical, heating, ventilation, plumbing and air-conditioning equipment and other service facilities shall be designed and/or otherwise elevated or located so as to prevent water from entering or accumulating within the components during conditions of flooding.

F. All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters into the system in accordance with the state of Oregon Building Codes and Plumbing Code.

G. All new construction, all manufactured homes and substantial improvements shall be anchored to prevent flotation, collapse and lateral movement of the structure.

H. New and replacement sanitary sewerage systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems and discharge from the systems into floodwaters. (Ord. 868, 2018; Ord. 813, 2010; Ord. 809, 2010; Ord. 634 § 1 Exh. A, 1995)

A. The following uses shall be permitted in special flood hazard areas and shall not require a permit under this chapter:

B. The following uses shall be permitted in special flood hazard areas and shall require a development permit under this Chapter in addition to any applicable federal, state or county permits:

C. A development permit shall be obtained before construction or development begins within any area of special flood hazard or drainageway unless specifically allowed in subsection A of this section. The permit shall apply to all structures including manufactured homes. (Ord. 868, 2018; Ord. 813, 2010; Ord. 809, 2010; Ord. 740 § 19, 2004; Ord. 636 § 1, 1996; Ord. 634 § 1 Exh. A, 1995)

A. The planner is appointed to administer and implement this chapter by granting or denying development permit applications in accordance with Chapter 17.162.

B. Duties of the planner shall include, but not be limited to:

C. When base flood elevation data has not been provided in accordance with Section 17.84.030, the applicant shall supply such data. In this instance, applications for building permits shall be reviewed to assure that proposed construction will be reasonably safe from flooding. The test of reasonableness includes use of historical data, high water marks, photographs of past flooding, etc., where available. Failure to elevate at least two feet above the highest adjacent grade in these zones may result in higher insurance rates.

D. The recipient of a development permit shall provide certification from a registered engineer, or surveyor that buildings are elevated or flood-proofed according to standards set forth in Section 17.84.140. Appropriate certification forms will be provided by the city.

E. A development permit shall not be issued for construction in Zone AE or Zone AO within the Scappoose Creek floodway fringe until the application satisfies the requirements set forth in Section 17.84.200.

F. Applicants receiving a development permit to construct or substantially improve a residential or nonresidential structure in Zones A or AE shall comply with applicable standards in Sections 17.84.140, and 17.84.200.

G. Applicants receiving a development permit to construct or substantially improve a residential or nonresidential structure in Zone AO shall comply with applicable standards in Section 17.84.140, 17.84.190 and 17.84.200.

H. A special land use permit, requiring planning commission approval, shall be obtained prior to storing or stockpiling buoyant or hazardous materials in a special flood hazard area. (See Section 17.84.210.) (Ord. 868, 2018; Ord. 813, 2010; Ord. 809, 2010; Ord. 634 § 1 Exh. A, 1995)

A. The applicant for a development permit shall be the recorded owner of the property or an agent authorized in writing by the owner.

B. The planner and public works director shall review all development permit applications to determine that all necessary permits are obtained from those federal, state, or local governmental agencies from which prior approval is also required.

C. The planner shall apply the standards set forth in this chapter when reviewing an application for a development permit. (Ord. 868, 2018; Ord. 813, 2010; Ord. 809, 2010; Ord. 634 § 1 Exh. A, 1995)

A. When base flood elevation data is provided through the Flood Insurance Study or required as in Section 17.84.050(C), the applicant shall provide certification of the actual elevation in relation to mean sea level of the lowest floor, including basement, of all new or substantially improved structures, and whether or not the structure contains a basement.

B. For all new or substantially improved floodproofed structures, the applicant shall submit a Floodproofing Certificate by a registered surveyor verifying and recording the actual elevation (in relation to mean sea level) prior to construction and the actual elevation (in relation to mean sea level) to which the structure was floodproofed.

C. The planner shall maintain the floodproofing certifications required in this chapter.

D. The planner shall maintain for public inspection all other records pertaining to the provisions in this chapter. (Ord. 868, 2018; Ord. 813, 2010; Ord. 809, 2010; Ord. 634 § 1 Exh. A, 1995)

A. The planner shall notify adjacent communities and the State Department of Land Conservation and Development prior to any alteration or relocation of a water course, and submit evidence of such notification to the Federal Insurance Administration.

B. The planner shall require that maintenance is provided within the altered or relocated portion of said watercourse so that the flood-carrying capacity is not diminished. (Ord. 868, 2018; Ord. 813, 2010; Ord. 809, 2010; Ord. 634 § 1 Exh. A, 1995)

A. Anchoring.

B. Construction Materials and Methods.

C. Utilities.

D. Subdivision Proposals.

E. New construction and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated to one foot or more above base flood elevation. 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 shall either be certified by a registered professional engineer or shall meet or exceed the following minimum criteria:

F. New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall either have the lowest floor, including basement, elevated to the level one foot or more above the base flood elevation or, together with attendant utility and sanitary facilities, shall:

G. Manufactured Homes. All manufactured homes to be placed or substantially improved in Areas of special flood hazard shall be placed on a permanent foundation such that the bottom of the longitudinal chassis frame beam is at or above base flood elevation. The permanent foundation shall be resistive to flood velocities and may include concrete slabs, stem walls, and piers that are firmly embedded in the ground. Manufactured homes may be placed on reinforced (not dry-stacked) concrete blocks providing the home is firmly anchored to the ground pursuant to this section. If placed on a stem wall, the structure shall meet the same standards for space below the lowest floor as described in subsection E of this section and the anchoring requirements of Section 17.84.140(A). Electrical crossover connections shall be a minimum of one foot above base flood elevation.

H. Recreational Vehicles. A recreational vehicle placed on site is required to either:

I. Accessory Structures. Accessory structures such as sheds, small detached garages, etc., to be located in Zone A, Zone AO, or Zone AE may be exempt from elevation provided the following conditions are met:

A. No filling operations of any kind shall be allowed in the floodway.

B. No fill in floodway fringe areas shall be allowed unless the net effect of excavation and filling operations (on-site) constitutes no positive change in fill volume, as certified by a registered professional engineer.

C. Fill shall be allowed under city fill permit procedures in shaded Zone X and shall not be regulated by this Chapter.

D. No structure shall be built nor any excavation grading, nor filling shall be done within the one hundred-year flood plain without first meeting the requirements of this chapter regulating construction, alteration, repair and moving of buildings. (Ord. 868, 2018; Ord. 828, 2013; Ord. 813, 2010; Ord. 809, 2010; Ord. 634 § 1 Exh. A, 1995)

A. Floodways are established in special flood hazard areas (SFHA) to transport the waters of a one hundred-year flood out of the community as quickly as possible. Encroachments on the floodway generally produce a rise in base flood elevations and contribute to other hydraulic problems. Accordingly, the city prohibits encroachments, including fill, new construction, parking, substantial improvements, and other development unless certification by a registered professional civil engineer is provided demonstrating through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge.

B. If subsection A above is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this chapter.

C. Projects for stream habitat restoration may be permitted in the floodway provided:

D. New installations of manufactured dwellings in floodways are prohibited. Manufactured dwellings may only be located in floodways according to one of the following conditions:

A. Zone AO is depicted on Flood Insurance Rate Maps (FIRMS). The zone coincides with areas subject to a one hundred-year flood where depths vary between one and three feet. Zone AO is associated with areas where sheet flow is most evident; i.e., where there is no clear channel. Flood depths appear on the FIRM.

B. Proposed construction in Zone AO shall comply with the General Standards provided in Section 17.84.140, excepting areas specifically covered in this section.

C. New construction and substantial improvements of residential structures in Zone AO shall:

D. New construction and substantial improvements of non-residential structures in Zone AO shall:

1. Density may be transferred only on contiguous lots under common ownership. Density may not be transferred to properties under different ownership.

2. A map shall be submitted showing the net buildable area outside of the floodplain to which the density will be transferred.

3. The portion of the parcel within the SFHA shall be dedicated to the City as open space unless the City determines the SFHA should be placed in a conservation easement.

4. The density of the buildable area may not be increased to more than one and one-half (1.5) times the permitted density of the underlying zone. Fractional units are to be rounded down to the next whole number.

5. Development shall only qualify for such a density bonus if any structures existing previous to the adoption of the floodplain ordinance are removed or relocated outside of the SFHA. (Ord. 868, 2018)

A. Proposed development or substantial improvement in the Scappoose Creek floodway fringe shall conform with applicable general and specific standards in Section 17.84.140, and special standards in Zone AO (Sections 17.84.190 and 17.84.200). (Ord. 868, 2018; Ord. 828, 2013; Ord. 813, 2010; Ord. 809, 2010; Ord. 634 § 1 Exh. A, 1995)

A. The transportation of buoyant or hazardous materials (Note: see Section 17.84.015, Definitions) from rising floodwaters contributes to the community's flood hazard. Accordingly, a permit shall be obtained from the planning commission prior to storage, placement or stockpiling in a flood hazard zone (A, AE, AO). The application shall be processed according to Chapter 17.162.

B. The placement, storage or stockpiling of buoyant or hazardous materials in a floodway is prohibited unless it is associated with a short-term public works project. The planning commission must consider the flood potential and establish a time in which the materials must be removed. (Ord. 868, 2018; Ord. 813, 2010; Ord. 809, 2010; Ord. 634 § 1 Exh. A, 1995)

A. A variance is a departure or grant of relief from the strict letter of the flood damage prevention chapter. It is designed for those situations where a proposed action is in keeping with the purpose of the chapter but there are practical difficulties in meeting strict chapter standards. The conditions for granting variances are stringent. When dealing with a flood hazard there is little margin for error.

B. All flood hazard variances are deemed to be a major variance as defined in Chapter 17.134 and shall be so administered and appealed.

C. The planner shall maintain the records of all appeal actions and report any variances to the Federal Emergency Management Agency (FEMA) upon request.

D. Variances may be issued for the reconstruction, rehabilitation or restoration of structures listed on the National Register of Historic Places or the State Inventory of Historic Places, without regard to the procedures set forth in this section.

E. Variances shall not be issued within a designated floodway.

F. Variances shall only be issued upon:

G. Variances as interpreted in the National Flood Insurance Program are based on the General Zoning Law Principle that they pertain to a physical piece of property; they are not personal in nature and do not pertain to the structure, its inhabitants, economic or financial circumstances. They primarily address small lots in densely populated residential neighborhoods. As such, variances from the flood elevations should be quite rare.

H. Variances may be issued for nonresidential buildings in very limited circumstances to allow a lesser degree of floodproofing than watertight or dry floodproofing, where it can be determined that such action will have low damage potential and complies with all other variance criteria.

I. Any applicant to whom a variance is granted shall be given notice that the structure will be permitted to be built with a lowest floor elevation below the base flood elevation and that the cost of flood insurance will be commensurate with the increased risk resulting from the reduced floor elevation. (Ord. 868, 2018; Ord. 813, 2010; Ord. 809, 2010; Ord. 634 § 1 Exh. A, 1995)

A. Approval of a development permit shall be void under any of the following circumstances:

B. The planner may, upon written request by the applicant, grant an extension of the start of construction for 180 days, provided that:

C. Notice of the decision shall be provided to the applicant. (Ord. 868, 2018; Ord. 813, 2010; Ord. 809, 2010; Ord. 634 § 1 Exh. A, 1995)

A. All applications shall be made on forms provided by the planner and shall be accompanied by:

B. The development plan and narrative may be combined on one map and shall include the following information: