Division I. Land Use
Chapter 15.05
Special Flood Hazard Areas
Sections:
15.05.010 Title.
15.05.020 Statement of purpose.
15.05.030 Definitions.
15.05.040 Basis for establishing special flood hazard areas.
15.05.050 Duties and responsibilities of the City Administrator.
15.05.060 Duties and responsibilities of the City Engineer.
15.05.070 Duties and responsibilities of the Building Official.
15.05.080 Criteria for issuance of development permits.
15.05.090 Variance provisions.
15.05.100 Appeals provisions.
15.05.010 Title.
This chapter shall be known as the "flood hazard ordinance of 1986" of the City of Brownsville, Oregon. [Ord. 507 § 1, 1980; 1981 Compilation § 8-6.1.]
15.05.020 Statement of purpose.
The purpose of this chapter shall be to promote the public health, safety and welfare of Brownsville residents by establishing regulations to minimize the negative impacts resulting from the temporary inundation of portions of the City during periodic flooding by the Calapooia River; to minimize damage to personal and real property and public facilities by establishing standards for development in flood prone areas; and to prevent development which may result in more severe flooding within the City. [Ord. 507 § 2, 1980; 1981 Compilation § 8-6.2.]
15.05.030 Definitions.
"Base flood" means the flood having a one percent chance of being equal to or exceeded in any given year (often referred to as a 100-year flood).
"Building Official" means the person, or authorized representative, licensed by the state of Oregon and charged with the responsibility to administer and enforce the provisions of the State Building Code.
"Building permit" means a permit issued by the Building Official to allow the commencement or construction or siting of a building or structure subsequent to review for conformance with the Uniform Building Code. "Building permit" shall include a mobile home permit.
"City Engineer" means a fully qualified registered professional engineer designated by the City Council to fulfill the responsibility of the City Engineer as specified in this chapter.
"Development" means any manmade change to improved or unimproved land, including but not limited to construction of buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations located within the area of special flood hazard.
"Development permit" means a permit authorized at the discretion of the City Administrator to allow any development, as defined in this section, within a special flood hazard area.
"Flood" or "flooding" means a general and temporary condition of partial or complete inundation of normally dry land areas by the unusual and rapid accumulation of runoff of inland waters from any source.
"Flood Insurance Rate Map (FIRM)" means the official map on which the Federal Insurance Administration has delineated both special flood hazard areas and the risk premium zones applicable to the City of Brownsville, Oregon.
"Flood Insurance Study" means the official report by the Federal Insurance Administration that includes flood profiles, the Flood Boundary – Floodway Map, and the water surface elevation of the base flood.
"Flood plain" or "special flood hazard area" means any dry land area susceptible to temporary inundation by surface waters during the occurrence of a base flood.
"Floodproofing" means any combination of structural or nonstructural additions, changes or adjustments to structures or mobile homes, including the contents thereof, which is intended to reduce or eliminate flood damage to property, public facilities, transportation facilities, structures, mobile homes, or their contents.
"Floodway" means the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than one foot.
"Habitable floor" means any floor usable for living purposes, which includes working, sleeping, eating, cooking, or recreation, or a combination thereof. A floor used solely for storage purposes is not a habitable floor.
"Structure" means a walled and roofed building, including a gas or liquid storage tank that is principally above ground, including a mobile home.
"Substantial improvement" means any repair, reconstruction 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 started, or (2) if the structure has been damaged and is being restored, before the damage occurs. "Substantial improvement" is considered to occur when the first alteration of any wall, ceiling, floor or other structural part of the building is commenced, whether or not the alteration affects the external dimensions of that structure. "Substantial improvement" does not include either (1) any project for improvements of the structure to comply with existing state or local health, sanitary or safety code specifications which are necessary to assure safe living conditions, or (2) any alteration of a structure listed on the National Register of Historic Places, in the Statewide Inventory of Historic Sites and Buildings for Linn County, or in the Brownsville Historic Inventory.
"Variance" means a permit reviewed by the Planning Commission and authorized by the City Council pursuant to BMC 15.05.090 to allow a means of alleviating such practical difficulties or unnecessary enforcement of the regulations of this chapter. A variance is not intended to subvert the intent of this chapter. [Ord. 507 § 3, 1980; 1981 Compilation § 8-6.3.]
15.05.040 Basis for establishing special flood hazard areas.
The areas of special flood hazard identified by the Federal Insurance Administration in the scientific and engineering report entitled "The Flood Insurance Study for the City of Brownsville" dated August 17, 1981, with accompanying flood insurance maps, is hereby adopted by reference and declared to be part of this chapter. The flood insurance study is on file at City Hall, 255 Main Street, Brownsville, Oregon. [Ord. 513 § 1, 1981; Ord. 507 § 4, 1980; 1981 Compilation § 8-6.4.]
15.05.050 Duties and responsibilities of the City Administrator.
The Brownsville City Administrator is hereby appointed to administer and implement the provisions of this chapter, and shall be charged with the following duties and responsibilities:
A. The City Administrator shall oversee the activities of the City Engineer and Building Official granted pursuant to the provisions of this chapter, and shall maintain a record of such activities.
B. The City Administrator shall periodically report on developmental activity in the special flood hazard area to the Brownsville City Council and Planning Commission.
C. The City Administrator shall review all applications for development permits filed pursuant to BMC 15.05.080, and shall determine if the requirements of this chapter have been satisfied, and if all applicable federal, state, county and local permits have been obtained. If the provisions of this chapter and all other applicable governmental regulations have been satisfied, the City Administrator shall be authorized to issue development permits.
D. The City Administrator shall interpret the exact location of the boundaries of the Flood Insurance Rate Maps. A person contesting the Administrator’s determination may appeal pursuant to BMC 15.05.100; all such appeals shall be granted consistent with the standards of Section 1910.6 of the rules and regulations of the National Flood Insurance Program (24 CFR 1909, etc.).
E. When base flood elevation data has not been provided in accordance with BMC 15.05.040, the City Administrator shall obtain, review and reasonably utilize any base flood elevation data available from a federal, state or other source as the basis for implementing provisions of this chapter.
F. The City Administrator shall obtain from the developer, and record, the actual elevation of the lowest habitable floor of all new or substantially improved structures, and whether or not the structure contains a basement. Such records shall be available for public inspection in the Brownsville City Hall during regular office hours.
G. The City Administrator shall notify the Federal Insurance Administration and all affected federal, state and county agencies prior to any alteration or relocation of a watercourse, and shall require that the flood carrying capacity of such watercourse not be diminished. [Ord. 507 § 5, 1980; 1981 Compilation § 8-6.5.]
15.05.060 Duties and responsibilities of the City Engineer.
The Brownsville City Engineer shall be charged with the following duties and responsibilities:
A. The City Engineer shall assist the City Administrator in completion of the duties and responsibilities assigned in BMC 15.05.050, and in particular shall assist in the review of applications for development permits, the interpretation of the FIRM boundaries, and in researching for flood elevation data not available pursuant to BMC 15.05.040.
B. The City Engineer shall review and report to the Planning Commission on all variances requested pursuant to BMC 15.05.090, and all appeals of an administrative determination filed pursuant to BMC 15.05.100, and shall assess and report the degree to which such applications comply with the intent and provisions of this chapter.
C. The City Engineer shall review all Comprehensive Plan and/or zone amendments, conditional use, subdivision, partition and variance requests proposed to be located within a special flood hazard area, and shall report to the Brownsville Planning Commission concerning the advisability of modifying or changing the land use designation given the severity of the flood hazard.
D. In the event that development is proposed within the floodway, the City Engineer shall review the type and scale of development, the engineering characteristics, and the registered engineer’s or hydrologist’s report to ascertain if such development would result in restricting the flow of flood waters. If, in the opinion of the City Engineer, the proposed development complies with the floodway standards of BMC 15.05.080, the City Engineer shall approve the proposed development. If, in the opinion of the City Engineer, the proposed development would restrict the flow of flood waters in the floodway, or would violate other provisions of BMC 15.05.080, the City Engineer shall deny the proposed development. [Ord. 507 § 6, 1980; 1981 Compilation § 8-6.6.]
15.05.070 Duties and responsibilities of the Building Official.
The Building Official is hereby authorized to issue building permits for construction in a special flood hazard area only if the applicant has obtained a development permit from the Brownsville City Administrator and/or City Engineer, issued pursuant to the provisions of BMC 15.05.080. [Ord. 507 § 7, 1980; 1981 Compilation § 8-6.7.]
15.05.080 Criteria for issuance of development permits.
A. A development permit issued by the Brownsville City Administrator shall be obtained prior to issuance of any federal, state, county or local permit regulating development as defined in BMC 15.05.030. Failure of the applicant to obtain a development permit prior to the start of construction shall stay any permits issued by any federal, state, county or local government entity.
B. The City Administrator, pursuant to BMC 15.05.050, shall review all applications for a development permit, and shall require that the below cited criteria applicable to the proposed use be satisfied prior to issuance of such permit.
1. Residential Construction.
a. New construction or substantial improvement of any residential structure shall have the lowest floor, including basement, elevated a minimum of one foot above base flood level.
b. Where elevation data is not available, applications for building permits shall be reviewed to assure that the proposed construction will be reasonably safe from flooding. The test of reasonability is a local judgement using such information as historical data, high water marks, photographs of past flooding, etc.
C. Proposed building sites shall be reasonably safe from flooding. If a proposed building site lies within a special flood hazard area, all new construction and substantial improvement shall be:
1. Designed and adequately anchored to prevent flotation, collapse or lateral movement of the structure;
2. Constructed with materials and utility equipment resistant to flood damage; and
3. Constructed using methods and practices that minimize flood damage.
D. An alternative method of anchoring designed to withstand a wind force of 90 miles per hour or greater and certified adequate by the City Engineer may be substituted for subsections (B) and (C)(1) of this section.
E. In any proposed residential construction, the flood carrying capacity within an altered or relocated portion of any watercourse shall be maintained.
1. Mobile Home Siting and Mobile Home Parks.
a. All mobile homes shall be anchored to resist flotation, collapse, or lateral movement by providing over-the-top and frame ties to ground anchors. Specific requirements shall be that:
i. Over-the-top ties be provided at each of the four corners of the mobile home, with two additional ties per side at intermediate locations, with mobile homes less than 50 feet long requiring one additional tie per side;
ii. Frame ties be provided at each corner of the home with five additional ties per side at intermediate points, with mobile homes less than 50 feet long requiring four additional ties per side;
iii. Each component of the anchoring system be capable of carrying a force of 4,800 pounds; and
iv. Any additions to the mobile home be similarly anchored.
b. For new mobile home parks and mobile home subdivisions; for expansions to existing mobile home parks and mobile home subdivisions where the repair, reconstruction or improvement of the streets, utilities and pads equals or exceeds 50 percent of value of the streets, utilities and pads before repair, reconstruction or improvement has commenced; and for mobile homes not placed in a mobile home park or mobile home subdivision, require that:
i. Stands or lots are elevated on compacted fill or pilings so that the lowest floor of the mobile home will be at or above the base flood level;
ii. Adequate surface drainage and access for a hauler are provided; and
iii. In the instance of elevation on pilings, that:
(A) Lots are large enough to permit steps;
(B) Piling foundations are placed in stable soil no more than 10 feet apart; and
(C) Reinforcement is provided for pilings more than six feet above the ground level.
c. No mobile home shall be placed in a floodway, except in an existing mobile home park or existing mobile home subdivision.
2. Nonresidential Construction.
a. All new construction and substantial improvement of nonresidential structures, including commercial, industrial and public structures, shall be anchored to a foundation to prevent movement during a flood, and have the lowest habitable floor (including basement) either elevated a minimum of one foot above the base flood level, or shall satisfy the below cited criteria:
i. The structure shall be floodproofed such that the portion of the structure below the base flood level is watertight, with walls substantially impermeable to the passage of water;
ii. The structural components shall be capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and
iii. Certification by a registered hydrologist or engineer shall be filed verifying that the standards of this subsection have been satisfied, and shall be reviewed and accepted only upon authorization of the City Engineer.
b. Materials, supplies, and equipment which are stored on any site within a special flood hazard area shall either be stored within an enclosed building or shall be located or anchored in such a way that their movement will not represent a potential obstruction to the natural flow of flood waters or a potential danger to the public safety.
3. Subdivision and Partition Proposals. All subdivision and partition proposals shall be consistent with the need to minimize flood damage, and shall incorporate the following design requirements into the proposed plat:
a. All subdivision and partition proposals shall have public utilities and facilities such as sewer, gas, electrical, and water systems located and constructed to minimize flood damage;
b. All subdivision and partition proposals shall have adequate drainage provided to reduce exposure to flood damage; and
c. Base flood elevation data shall be provided for subdivision and partition proposals.
4. Utilities Construction.
a. All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters 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 system into flood waters; and
c. On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.
5. Street Construction. All new streets or improvements to existing streets located in a special flood hazard area shall be so constructed as to not be subject to inundation, or be rendered impassable to either private or emergency vehicles during periodic flooding.
6. Floodway Development. Located within areas of special flood hazard established in BMC 15.05.040 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of flood waters which carry debris, potential projectiles, and erosion potential, the following provisions apply:
a. Encroachments, including fill, new construction, substantial improvements, and other development shall be prohibited unless certification by a registered hydrologist is provided demonstrating that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge, and will not cause flooding in areas that have not been flooded before.
b. All new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this chapter; and
c. The placement of any mobile homes, except in an existing mobile home park or existing mobile home subdivision, is prohibited. [Ord. 507 § 8, 1980; 1981 Compilation § 8-6.8.]
15.05.090 Variance provisions.
Application for a variance to provisions of this chapter shall be filed with the City Administrator, and shall be reviewed by the Planning Commission with the assistance of the City Engineer.
A. When reviewing an application for a variance to the provisions of this chapter, the Planning Commission shall consider the following factors in relation to the particular request:
1. The danger that materials may be swept onto other lands to the injury of others;
2. The danger to life and property due to flooding or erosion damage;
3. The susceptibility of the proposed facility and its contents to flood damage and the effect of such damage on the individual owner;
4. The importance of the services provided by the proposed facility to the community;
5. The necessity to the facility of a waterfront location, where applicable;
6. The availability of alternative locations for the proposed use which are not subject to flooding or erosion damage;
7. The compatibility of the proposed use with existing and anticipated development;
8. The relationship of the proposed use to the Comprehensive Plan and flood plain management program for that area;
9. The safety of access to the property in times of flood for private and emergency vehicles;
10. The expected heights, velocity, duration, rate of rise, and sediment transport of the flood waters and the effects of wave action, if applicable, expected at the site; and
11. The costs of providing governmental services during and after flood conditions, including maintenance and repair of public utilities and facilities such as sewer, gas, electrical, and water systems, and streets and bridges.
B. A variance may be granted by the Planning Commission only upon finding:
1. That the variance is the minimum necessary, considering the flood hazard, to afford relief; and
2. That failure to grant the request will result in an unnecessary hardship; and
3. That granting of the variance will not result in increased flood heights, additional threats to public safety or extraordinary public expense, or create a nuisance or conflict with state or local laws or ordinances; and
4. That a public need for the proposed development presently exists; and
5. That the granting of a variance will not jeopardize the status of structures listed on the National Register of Historic Places, Oregon Statewide Inventory of Historic Buildings and Sites, or Brownsville Historic Inventory; and
6. That the granting of a variance request for construction in the floodway will not increase the elevation of the base flood.
C. The Planning Commission may place any conditions or stipulations on the granting of a variance request as are deemed necessary to further the purposes of this chapter.
D. Upon the Planning Commission authorization approving a variance, the City Administrator shall be authorized to approve the issuance of a building permit by the Building Official. A copy of the approval shall be maintained in the records of the City of Brownsville, and a report on the approval shall be forwarded to the Federal Insurance Administration. [Ord. 507 § 9, 1980; 1981 Compilation § 8-6.9.]
15.05.100 Appeals provisions.
A. The Brownsville Planning Commission shall be designated the authorized body to review all appeals filed by a property owner or affected citizen in reference to the following:
1. A determination by the City Administrator as to the exact location of the boundaries of the Flood Insurance Rate Maps or other base flood elevation data;
2. A determination by the City Administrator not to issue a development permit pursuant to the provisions of BMC 15.05.080;
3. Any other determination by the City Administrator as to the provisions of this chapter.
B. The Planning Commission may approve an appeal of a determination made by the City Administrator only if the following findings are made:
1. That the City Administrator has erred in the interpretation of the Flood Insurance Rate Map boundaries or in the interpretation of the provisions of this chapter; or
2. That the applicant has submitted engineering, hydrological or other studies which substantiate that the elevations found on the Flood Insurance Rate Maps are in error.
C. A determination of the Planning Commission may be appealed by a property owner or affected citizen to the City Council within 10 days of the date of decision. In reviewing such an application, the City Council must apply the criteria in subsection (B) of this section to approve the appeals. [Ord. 507 § 11, 1980; 1981 Compilation § 8-6.10.]