(1)   The flood hazard areas of City of North Plains preserve the natural and beneficial values served by floodplains but are subject to periodic inundation which may result 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 the tax base, all of which adversely affect the public health, safety, and general welfare.

      (2)   These flood losses may be caused by the cumulative effect of obstructions in special flood hazard areas which increase flood heights and velocities, and when inadequately anchored, cause damage in other areas. Uses that are inadequately floodproofed, elevated, or otherwise protected from flood damage also contribute to flood loss.

      (1)   Protect human life and health;

      (2)   Minimize expenditure of public money for costly flood control projects;

      (3)   Preserve natural and beneficial floodplain functions;

      (4)   Minimize the need for rescue and relief efforts associated with flooding and generally undertaken at the expense of the general public;

      (5)   Minimize prolonged business interruptions;

      (6)   Minimize damage to public facilities and utilities such as water and gas mains; electric, telephone and sewer lines; and streets and bridges located in special flood hazard areas;

      (7)   Help maintain a stable tax base by providing for the sound use and development of flood hazard areas so as to minimize blight areas caused by flooding;

      (8)   Notify potential buyers that the property is in a special flood hazard area;

      (9)   Notify those who occupy special flood hazard areas that they assume responsibility for their actions; and

      (10)   Participate in and maintain eligibility for flood insurance and disaster relief.

      (1)   Restricting or prohibiting development which is dangerous to health, safety, and property due to water or erosion hazards, or which result in damaging increases in erosion or in flood heights or velocities;

      (2)   Requiring that development vulnerable to floods, including facilities which serve such uses, be protected against flood damage at the time of initial construction;

      (3)   Controlling the alteration of natural floodplains, stream channels, and natural protective barriers, which help accommodate or channel flood waters;

      (4)   Controlling filling, grading, dredging, and other development which may increase flood damage;

      (5)   Preventing or regulating the construction of flood barriers which will unnaturally divert flood waters or may increase flood hazards in other areas; and

      (6)   Employing a standard of “no net loss” of natural and beneficial floodplain functions.

(Ord. 499, passed 9-15-2025)

   Unless specifically defined below, words or phrases used in this subchapter shall be interpreted so as to give them the meaning they have in common usage.

      (1)   A general and temporary condition of partial or complete inundation of normally dry land areas from:

         (a)   The overflow of inland or tidal waters.

         (b)   The unusual and rapid accumulation or runoff of surface waters from any source.

         (c)   Mudslides (i.e., mudflows) which are proximately caused by flooding as defined in division (1)(b) of this definition and are akin to a river of liquid and flowing mud on the surfaces of normally dry land areas, as when earth is carried by a current of water and deposited along the path of the current.

            (2)   The collapse or subsidence of land along the shore of a lake or other body of water as a result of erosion or undermining caused by waves or currents of water exceeding anticipated cyclical levels 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 flash flood or an abnormal tidal surge, or by some similarly unusual and unforeseeable event which results in flooding as defined in division (1)(a) of this definition.

      (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 Interior; or

      (4)   Individually listed on a local inventory of historic places in communities with historic preservation programs that have been certified either:

         (a)   By an approved state program as determined by the Secretary of the Interior; or

         (b)   Directly by the Secretary of the Interior in states without approved programs.

      (1)   Has a minimum of a bachelor’s degree in wildlife or fisheries habitat biology, or a related degree in a biological field from an accredited college or university with a minimum of four years’ experience as a practicing wildlife or fish habitat biologist; or

      (2)   Is listed on the Oregon Department of Transportation’s official list of consultants qualified to provide Endangered Species Act documentation.

      (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.

      (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

(Ord. 499, passed 9-15-2025)

      (1)   Considered as minimum requirements;

      (2)   Liberally construed in favor of the governing body; and

      (3)   Deemed neither to limit nor repeal any other powers granted under state statutes.

(Ord. 499, passed 9-15-2025)

   The Planning Manager is hereby appointed to administer, implement, and enforce this subchapter by granting or denying development permits in accordance with its provisions. The Floodplain Administrator may delegate authority to implement these provisions.

(Ord. 499, passed 9-15-2025)

   Duties of the Floodplain Administrator, or their designee, shall include, but not be limited to:

      (1)   Determine that the permit requirements of this subchapter have been satisfied;

      (2)   Determine that all other required local, state, and federal permits have been obtained and approved; and

      (3)   Determine if the proposed development is located in a floodway.

         (a)   If located in the floodway assure that the floodway provisions of this subchapter in § 155.339 are met;

         (b)   Determine if the proposed development is located in an area where base flood elevation (BFE) data is available either through the flood insurance study (FIS) or from another authoritative source. If BFE data is not available then ensure compliance with the provisions of § 155.337(G); and

         (c)   Provide to building officials the elevation one foot above base flood elevation (BFE) applicable to any building requiring a development permit.

      (4)   Determine if the proposed development qualifies as a substantial improvement as defined in § 155.331.

      (5)   Determine if the proposed development activity is a watercourse alteration. If a watercourse alteration is proposed, ensure compliance with the provisions in § 155.337(A).

      (6)   Determine if the proposed development activity includes the placement of fill or excavation.

      (7)   Determine whether the proposed development activity complies with the mitigation standards in §§ 155.341 through 155.343.

      (1)   The actual elevation (in relation to mean sea level) of the lowest floor (including basements) and all attendant utilities of all new or substantially improved structures where base flood elevation (BFE) data is provided through the flood insurance study (FIS), flood insurance rate map (FIRM), or obtained in accordance with § 155.337(G).

      (2)   The elevation (in relation to mean sea level) of the natural grade of the building site for a structure prior to the start of construction and the placement of any fill and ensure that the requirements of division (A)(2) and § 155.339 are adhered to.

      (3)   Upon placement of the lowest floor of a structure (including basement) but prior to further vertical construction, documentation, prepared and sealed by a professional licensed surveyor or engineer, certifying the elevation (in relation to mean sea level) of the lowest floor (including basement).

      (4)   Where base flood elevation data are utilized, as-built certification of the elevation (in relation to mean sea level) of the lowest floor (including basement) prepared and sealed by a professional licensed surveyor or engineer, prior to the final inspection.

      (5)   Maintain all elevation certificates (EC) submitted to the community.

      (6)   The elevation (in relation to mean sea level) to which the structure and all attendant utilities were floodproofed for all new or substantially improved floodproofed structures where allowed under this subchapter and where base flood elevation (BFE) data is provided through the FIS, FIRM, or obtained in accordance with § 155.337(G).

      (7)   All floodproofing certificates required under this subchapter.

      (8)   All variance actions, including justification for their issuance.

      (9)   All hydrologic and hydraulic analyses performed as required under § 155.339.

      (10)   All substantial improvement and substantial damage calculations and determinations as required under division (D).

      (11)   Documentation of how mitigation standards have been met (see §§ 155.341 through 155.343).

      (12)   All records pertaining to the provisions of this subchapter.

         (a)   Notify adjacent communities, the Department of Land Conservation and Development, and other appropriate state and federal agencies, prior to any alteration or relocation of a watercourse, and submit evidence of such notification to the Federal Insurance Administration. This notification shall be provided by the applicant to the Federal Insurance Administration as a letter of map revision (LOMR) along with either:

            1.   A proposed maintenance plan to assure the flood carrying capacity within the altered or relocated portion of the watercourse is maintained; or

            2.   Certification by a registered professional engineer that the project has been designed to retain its flood carrying capacity without periodic maintenance.

         (b)   The applicant shall be required to submit a conditional letter of map revision (CLOMR) when required under division (C)(3). Ensure compliance with all applicable requirements in division (C)(3) and § 155.337(A).

         (a)   A community’s base flood elevations may increase or decrease resulting from physical changes affecting flooding conditions. As soon as practicable, but not later than six months after the date such information becomes available, a community shall notify the Federal Insurance Administrator of the changes by submitting technical or scientific data in accordance with Title 44 of the Code of Federal Regulations (CFR), § 65.3. The community may require the applicant to submit such data and review fees required for compliance with this section through the applicable FEMA letter of map change (LOMC) process.

         (b)   The Floodplain Administrator shall require a conditional letter of map revision prior to the issuance of a floodplain development permit for:

            1.   Proposed floodway encroachments that increase the base flood elevation; and

            2.   Proposed development which increases the base flood elevation by more than one foot in areas where FEMA has provided base flood elevations but no floodway.

         (c)   An applicant shall notify FEMA within six months of project completion when an applicant has obtained a conditional letter of map revision (CLOMR) from FEMA. This notification to FEMA shall be provided as a letter of map revision (LOMR).

(Ord. 499, passed 9-15-2025)

      (1)   In riverine flood zones, the proposed elevation (in relation to mean sea level), of the lowest floor (including basement) and all attendant utilities of all new and substantially improved structures; in accordance with the requirements of § 155.334(B).

      (2)   Proposed elevation in relation to mean sea level to which any nonresidential structure will be floodproofed.

      (3)   Certification by a registered professional engineer or architect licensed in the State of Oregon that the floodproofing methods proposed for any nonresidential structure meet the floodproofing criteria for non-residential structures in § 155.338(C)(3).

      (4)   Description of the extent to which any watercourse will be altered or relocated.

      (5)   Base flood elevation data for subdivision proposals or other development when required per § 155.334(A) and § 155.337(F).

      (6)   Substantial improvement calculation for any improvement, addition, reconstruction, renovation, or rehabilitation of an existing structure.

      (7)   The amount and location of any fill or excavation activities proposed.

(Ord. 499, passed 9-15-2025)

   The issuance of a variance is for floodplain management purposes only. Flood insurance premium rates are determined by federal statute according to actuarial risk and will not be modified by the granting of a variance.

      (1)   Generally, variances may be issued for new construction and substantial improvements to be erected on a lot of one-half acre or less in size contiguous to and surrounded by lots with existing structures constructed below the base flood level, in conformance with the provisions of divisions (A)(3), (A)(5), and (B). As the lot size increases beyond one-half acre, the technical justification required for issuing a variance increases.

      (2)   Variances shall only be issued upon a determination that the variance is the minimum necessary, considering the flood hazard, to afford relief.

      (3)   Variances shall not be issued within any floodway if any increase in flood levels during the base flood discharge would result.

      (4)   Variances shall only be issued 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 laws or ordinances.

      (5)   Variances may be issued by a community for new construction and substantial improvements and for other development necessary for the conduct of a functionally dependent use provided that the criteria of divisions (A)(2) through (A)(4) are met, and 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.

      (6)   Variances shall not be issued unless it is demonstrated that the development is properly mitigated (see §§ 155.341 through 155.343 and associated options in Table 1).

(Ord. 499, passed 9-15-2025)

   In all special flood hazard areas, the mitigation standards (see §§ 155.341 through 155.343) and the following standards shall be adhered to:

      (1)   All new construction and substantial improvements shall be anchored to prevent flotation, collapse, or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy.

      (2)   All manufactured dwellings shall be anchored per § 155.338(C)(4).

      (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.

         (a)   All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the system.

         (b)   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.

         (c)   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.

         (a)   If replaced as part of a substantial improvement shall meet all the requirements of this section.

      (1)   Underground tanks shall be anchored to prevent flotation, collapse and lateral movement under conditions of the base flood.

      (2)   Above-ground tanks shall be installed at or abve one foot above the base flood level or shall be anchored to prevent flotation, collapse, and lateral movement under conditions of the base flood.

      (1)   All new subdivision proposals and other proposed new developments (including proposals for manufactured dwelling parks and subdivisions) greater than 50 lots or five acres, whichever is the lesser, shall include within such proposals base flood elevation data.

      (2)   All new subdivision proposals and other proposed new developments (including proposals for manufactured dwelling parks and subdivisions) shall:

         (a)   Be consistent with the need to minimize flood damage.

         (b)   Have public utilities and facilities such as sewer, gas, electrical, and water systems located and constructed to minimize or eliminate flood damage.

         (c)   Have adequate drainage provided to reduce exposure to flood hazards.

         (d)   Comply with mitigation standards in §§ 155.341 through 155.343.

      (1)   When base flood elevation data has not been provided in accordance with § 155.332(B) the local Floodplain Administrator shall obtain, review, and reasonably utilize any base flood elevation data available from a federal, state, or other source, in order to administer § 155.337 through 155.340. All new subdivision proposals and other proposed new developments (including proposals for manufactured dwelling parks and subdivisions) must meet the requirements of division (F).

      (2)   Base flood elevations shall be determined for development proposals that are five acres or more in size or are 50 lots or more, whichever is lesser in any A Zone that does not have an established base flood elevation. Development proposals located within a riverine unnumbered A Zone shall be reasonably safe from flooding; the test of reasonableness includes use of historical data, high water marks, FEMA provided base level engineering data, and photographs of past flooding, etc. where available. (Reference to any of this type of information to be used for regulatory purposes by your community, i.e. base level engineering data, high water marks, historical or other data that will be regulated to. This may be necessary to ensure that the standards applied to residential structures are clear and objective. If uncertain seek legal advice, at a minimum require the elevation of residential structures and non-residential structures that are not dry floodproofed to be two feet above highest adjacent grade.) Failure to elevate at least two feet above grade in these zones may result in higher insurance rates.

      (1)   When a structure is located in multiple flood zones on the community’s flood insurance rate maps (FIRM) the provisions for the more restrictive flood zone shall apply.

      (2)   When a structure is partially located in a special flood hazard area, the entire structure shall meet the requirements for new construction and substantial improvements.

(Ord. 499, passed 9-15-2025)

   These specific standards shall apply to all new construction and substantial improvements in addition to the general standards contained in § 155.337 and the mitigation standards (see § 155.341).

      (1)   Be designed to automatically equalize hydrostatic flood forces on walls by allowing for the entry and exit of floodwaters;

      (2)   Be used solely for parking, storage, or building access;

      (3)   Be certified by a registered professional engineer or architect or meet or exceed all of the following minimum criteria:

         (a)   A minimum of two openings;

         (b)   The total net area of non-engineered openings shall be not less than one square inch for each square foot of enclosed area, where the enclosed area is measured on the exterior of the enclosure walls;

         (c)   The bottom of all openings shall be no higher than one foot above grade;

         (d)   Openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they shall allow the automatic flow of floodwater into and out of the enclosed areas and shall be accounted for in the determination of the net open area; and

         (e)   All additional higher standards for flood openings in the State of Oregon Residential Specialty Codes § R322.2.2 shall be complied with when applicable.

      (1)   Attached garages may be constructed with the garage floor slab below the base flood elevation (BFE) in riverine flood zones, if the following requirements are met:

         (a)   If located within a floodway the proposed garage must comply with the requirements of § 155.339;

         (b)   The floors are at or above grade on not less than one side;

         (c)   The garage is used solely for parking, building access, and/or storage;

         (d)   The garage is constructed with flood openings in compliance with division (A) to equalize hydrostatic flood forces on exterior walls by allowing for the automatic entry and exit of floodwater;

         (e)   The portions of the garage constructed below the BFE are constructed with materials resistant to flood damage;

         (f)   The garage is constructed in compliance with the standards in § 155.337; and

         (g)   The garage is constructed with electrical, and other service facilities located and installed so as to prevent water from entering or accumulating within the components during conditions of the base flood.

      (2)   Detached garages must be constructed in compliance with the standards for appurtenant structures in division (C)(6) or non-residential structures in division (C)(3) depending on the square footage of the garage.

         (a)   New construction, conversion to, and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated at or above one foot above base flood elevation (BFE).

         (b)   Enclosed areas below the lowest floor shall comply with the flood opening requirements in division (A).

         (a)   New construction, conversion to, and substantial improvement of any commercial, industrial, or other non-residential structure shall:

            1.   Have the lowest floor, including basement elevated at or above one foot above base flood elevation (BFE); or

            2.   Together with attendant utility and sanitary facilities:

               a.   Be floodproofed so that below the base flood level 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 design and methods of construction are in accordance with accepted standards of practice for meeting provisions of this section based on their development and/or review of the structural design, specifications and plans. Such certifications shall be provided to the Floodplain Administrator as set forth § 155.334(B).

         (b)   Non-residential structures that are elevated, not floodproofed, shall comply with the standards for enclosed areas below the lowest floor in division (A).

         (c)   Applicants floodproofing non-residential buildings shall be notified that flood insurance premiums will be based on rates that are one foot below the floodproofed level (e.g. a building floodproofed to the base flood level will be rated as one foot below).

         (a)   Manufactured dwellings to be placed (new or replacement) or substantially improved that are supported on solid foundation walls shall be constructed with flood openings that comply with division (A);

         (b)   The bottom of the longitudinal chassis frame beam shall be at or above base flood elevation;

         (d)   Electrical crossover connections shall be a minimum of 12 inches above base flood elevation (BFE).

         (a)   Be on the site for fewer than 180 consecutive days; and

         (b)   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

         (c)   Meet the requirements of division (C)(4), including the anchoring and elevation requirements for manufactured dwellings.

         (a)   Appurtenant structures located partially or entirely within the floodway must comply with requirements for development within a floodway found in § 155.339;

         (b)   Appurtenant structures must only be used for parking, access, and/or storage and shall not be used for human habitation;

         (c)   In compliance with State of Oregon Specialty Codes, appurtenant structures on properties that are zoned residential are limited to one-story structures less than 200 square feet, or 400 square feet if the property is greater than two acres in area and the proposed appurtenant structure will be located a minimum of 20 feet from all property lines. Appurtenant structures on properties that are zoned as non-residential are limited in size to 120 square feet;

         (d)   The portions of the appurtenant structure located below the base flood elevation must be built using flood resistant materials;

         (e)   The appurtenant structure must be adequately anchored to prevent flotation, collapse, and lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy, during conditions of the base flood;

         (f)   The appurtenant structure must be designed and constructed to equalize hydrostatic flood forces on exterior walls and comply with the requirements for flood openings in division (A);

         (g)   Appurtenant structures shall be located and constructed to have low damage potential;

         (h)   Appurtenant structures shall not be 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 § 155.337(E); and

         (i)   Appurtenant structures shall be constructed with electrical, mechanical, and other service facilities located and installed so as to prevent water from entering or accumulating within the components during conditions of the base flood.

(Ord. 499, passed 9-15-2025)

   Located within the special flood hazard areas established in § 155.332(B) are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of the floodwaters which carry debris, potential projectiles, and erosion potential, the following provisions apply:

   (A)   Prohibit encroachments, including fill, new construction, substantial improvements, and other development within the adopted regulatory floodway unless:

      (1)   Certification by a registered professional civil engineer is provided demonstrating through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that the proposed encroachment shall not result in any increase in flood levels within the community during the occurrence of the base flood discharge; or

      (2)   A community may permit encroachments within the adopted regulatory floodway that would result in an increase in base flood elevations, provided that conditional approval has been obtained by the Federal Insurance Administrator through the conditional letter of map revision (CLOMR) application process, all requirements established under 44 CFR § 65.12 are fulfilled, and the encroachment(s) comply with the mitigation standards in § 155.341.

   (B)   If the requirements of division (A) are satisfied, all new construction, substantial improvements, and other development shall comply with all other applicable flood hazard reduction provisions of this chapter.

(Ord. 499, passed 9-15-2025)

   Shallow flooding areas appear on FIRMs as AO Zones with depth designations or as AH Zones with base flood elevations. For AO Zones the base flood depths range from one to three feet above ground 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. For both AO and AH Zones, adequate drainage paths are required around structures on slopes to guide floodwaters around and away from proposed structures.

      (1)   New construction, conversion to, and substantial improvement of residential structures and manufactured dwellings within AO Zones shall have the lowest floor, including basement, elevated above the highest grade adjacent to the building, at minimum to or above one foot above the depth number specified on the flood insurance rate maps (FIRM) (at least two feet if no depth number is specified). For manufactured dwellings the lowest floor is considered to be the bottom of the longitudinal chassis frame beam.

      (2)   New construction, conversion to, and substantial improvements of non-residential structures within AO Zones shall either:

         (a)   Have the lowest floor (including basement) elevated above the highest adjacent grade of the building site, at minimum to or above one foot above the depth number specified on the flood insurance rate maps (FIRMS) (at least two feet if no depth number is specified); or

         (b)   Together with attendant utility and sanitary facilities, be completely floodproofed to or above one foot above the depth number specified on the FIRM or a minimum of two feet above the highest adjacent grade if no depth number is specified, 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 the effects of buoyancy. If this method is used, compliance shall be certified by a registered professional engineer or architect as stated in § 155.338.

      (3)   Recreational vehicles placed on sites within AO Zones on the community’s flood insurance rate maps (FIRM) shall either:

         (a)   Be on the site for fewer than 180 consecutive days; and

         (b)   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

         (c)   Meet the elevation requirements of division (B)(1) and the anchoring and other requirements for manufactured dwellings of § 155.338(C)(4).

      (4)   In AO Zones, new and substantially improved appurtenant structures must comply with the standards in § 155.338(C)(6).

      (5)   In AO Zones, enclosed areas beneath elevated structures shall comply with the requirements in 155.338(A).

(Ord. 499, passed 9-15-2025)

   This section applies to all special flood hazard areas described in § 155.331.

   (A)   An application for a development permit shall include documentation of one of the following:

      (1)   Confirmation that the applicant has obtained a floodplain mitigation assessment of the proposed development performed by a qualified professional and;

         (a)   A site plan, design plan, or other drawings clearly showing the mitigation measures identified in the floodplain mitigation assessment as necessary to achieve no net loss of floodplain functions;

      (2)   Coverage of the proposed development by the consultation and biological opinion issued by the National Oceanic and Atmospheric Administration’s National Marine Fisheries Service (NMFS) for the Federal Emergency Management Agency’s implementation of the National Flood Insurance Program in Oregon (NMFS Consultation No. NWR-2011-3197) and another formal consultation with NMFS or the United States Fish and Wildlife Service, pursuant to §§ 4(d), 7, or 10 of the Endangered Species Act of 1973;

      (3)   Confirmation that the proposed development fits within the nature and scope of the project types that are addressed in an existing full programmatic habitat assessment of all current and reasonably foreseeable future conditions; or

      (4)   Statement that the proposed development consists only of one or more of the following exempted activities:

         (a)   Normal maintenance, repairs, or remodeling of structures, such as re-roofing and replacing siding, provided the proposed activity does not:

            1.   Alter the footprint or expand the roof of the structure; or

            2.   Constitute a substantial improvement or repair of substantial damage.

         (b)   Normal street, sidewalk, and road maintenance, including filling potholes, repaving, and installing signs and traffic signals, that does not alter contours, use, or alter culverts; but not including expansion of paved areas;

         (c)   Routine maintenance of landscaping that does not involve grading, excavation, or filling;

         (d)   Routine agricultural practices such as tilling, plowing, harvesting, soil amendments, and ditch cleaning that does not alter the ditch configuration provided the spoils are removed from special flood hazard area or tilled into fields as a soil amendment;

         (e)   Routine silviculture practices that do not meet the definition of development, including harvesting of trees as long as root balls are left in place and forest road construction or maintenance that does not alter contours, use, or alter culverts;

         (f)   Removal of noxious weeds and hazard trees, and replacement of non-native vegetation with native vegetation;

         (g)   Normal maintenance of above and below ground utilities and facilities, such as replacing downed power lines and utility poles provided there is no net change in footprint;

         (h)   Normal maintenance of a levee or other flood control facility prescribed in the operations and maintenance plan for the levee or flood control facility. Normal maintenance does not include repair from flood damage, expansion of the prism, expansion of the face or toe or addition of protection on the face or toe with rock armor;

         (i)   Habitat restoration activities;

         (j)   Activities with the sole purpose of creating, restoring, or enhancing natural functions associated with floodplains, streams, lake, estuaries, marine areas, habitat, and riparian areas, provided the activities meet federal and state standards and do not include structures, grading, fill, or impervious surfaces;

         (k)   Repair to onsite septic systems, provided ground disturbance is the minimal necessary and best management practices are utilized to prevent stormwater runoff and soil erosion; and

         (l)   Pre-emptive removal of documented susceptible trees to manage the spread of invasive species.

   (B)   A development permit application will be denied unless the application includes the information described in division (A) of this section.

(Ord. 499, passed 9-15-2025)

   Any development proposal that cannot achieve no net loss of pervious surfaces must include the following:

   (A)   Water quality (pollution reduction) treatment for post-construction stormwater runoff from any net increase in impervious area; and

   (B)   Water quantity treatment (retention facilities) unless the outfall discharges into the ocean;

   (C)   Retention facilities must:

      (1)   Limit discharge to match the pre-development peak discharge rate (i.e., the discharge rate of the site based on its natural groundcover and grade before any development occurred) for the ten-year peak flow using a continuous simulation for flows between 50% of the two-year event and the ten-year flow event (annual series).

      (2)   Treat stormwater to remove sediment and pollutants from impervious surfaces such that at least 80% of the suspended solids are removed from the stormwater prior to discharging to the receiving water body.

      (3)   Be designed to not entrap fish and drain to the source of flooding.

      (4)   Be certified by a qualified professional.

   (D)   Stormwater treatment practices for multi-parcel facilities, including subdivisions, shall have an enforceable operation and maintenance agreement to ensure the system functions as designed. This agreement will include:

      (1)   Access to stormwater treatment facilities at the site by the city for the purpose of inspection and repair.

      (2)   A legally binding document specifying the parties responsible for the proper maintenance of the stormwater treatment facilities. The agreement will be recorded and bind subsequent purchasers and sellers even if they were not party to the original agreement.

      (3)   For stormwater controls that include vegetation and/or soil permeability, the operation and maintenance manual must include maintenance of these elements to maintain the functionality of the feature.

      (4)   The responsible party for the operation and maintenance of the stormwater facility shall have the operation and maintenance manual on site and available at all times. Records of the maintenance and repairs shall be retained and made available for inspection by the city for five years.

(Ord. 499, passed 9-15-2025)

   (A)   The riparian buffer zone is measured from the ordinary high-water line of a fresh waterbody (lake; pond; ephemeral, intermittent, or perennial stream) or mean higher-high water of a marine shoreline or tidally influenced river reach to 170 feet horizontally on each side of the stream or inland of the MHHW. The riparian buffer zone includes the area between these outer boundaries on each side of the stream, including the stream channel.

   (B)   Habitat restoration activities in the RBZ are considered self-mitigating and are not subject to the mitigation standards described above.

   (C)   Functionally dependent uses are only subject to the no net loss standards (Table 1) for development in the RBZ. Ancillary features that are associated with but do not directly impact the functionally dependent use in the RBZ (including manufacturing support facilities and restrooms) are subject to the beneficial gain standard in addition to no net loss standards.

   (D)   Any other use of the RBZ requires a greater offset to achieve no net loss of floodplain functions, on top of the no net loss standards described above, through the beneficial gain standard.

   (E)   Under FEMA’s beneficial gain standard, an area within the same reach of the project and equivalent to 5% of the total project area within the RBZ shall be planted with native herbaceous and shrub vegetation and designated as open space.

 

(Ord. 499, passed 9-15-2025)