Chapter 16.05
FLOOD DAMAGE PREVENTION

Sections:

Article I. Statutory Authorization, Findings of Fact, Purpose, and Objectives

16.05.010    Statutory authorization.

16.05.020    Statement of purpose.

Article II. Definitions

16.05.030    Definitions.

Article III. General Provisions

16.05.040    Lands to which this chapter applies.

16.05.050    Basis for establishing the areas of special flood hazard.

Article IV. Administration

16.05.060    Development permit required.

16.05.070    Designation of the city administrator or designee.

16.05.080    Duties and responsibilities of the city administrator or designee.

Article V. Provisions for Flood
Hazard Reduction

16.05.090    General standards.

16.05.100    Specific standards.

16.05.110    Floodways.

Article I. Statutory Authorization, Findings of Fact, Purpose, and Objectives

16.05.010 Statutory authorization.

The Legislature of the state of Oregon has, in ORS Chapter 197, delegated the responsibility to local governmental units to adopt regulations designed to promote the public health, safety, and general welfare of its citizenry. Therefore, the common council of the city of Hubbard, state of Oregon, ordains the provisions of this chapter. (Ord. 128-88 § 1.1, 1988)

16.05.020 Statement of purpose.

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 flood conditions in specific areas by provisions designed to:

(1) Protect human life and health;

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

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

(4) Minimize prolonged business interruptions;

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

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

(7) Ensure that potential buyers are notified that property is in an area of special flood hazard; and

(8) Ensure that those who occupy the areas of special flood hazard assume responsibility for their actions. (Ord. 128-88 § 1.3, 1988)

Article II. Definitions

16.05.030 Definitions.

Unless specifically defined below, 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.

“Area of special flood hazard” means the land in the floodplain within a community subject to a one percent or greater chance of flooding in any given year. Designation on maps always includes the letters “A” or “V.”

“Base flood” means the flood having a one percent chance of being equalled or exceeded in any given year. Also referred to as the “100-year flood.” Designation on maps always includes the letters “A” or “V.”

“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 located within the area of special flood hazard.

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

(a) The overflow of inland or tidal waters; and/or

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

“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 cumulatively increasing the water surface elevation more than one foot.

“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 found at HMC 16.05.100(1)(b).

“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 connected to the required utilities. For floodplain management purposes the term “manufactured home” also includes park trailers, travel trailers, and other similar vehicles placed on a site for greater than 180 consecutive days. For insurance purposes the term “manufactured home” does not include park trailers, travel trailers, and other similar vehicles.

“New construction” means structures for which the “start of construction” commenced on or after the effective date of the ordinance codified in this chapter.

“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 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.

“Structure” means a walled and roofed building including a gas or liquid storage tank that is principally above ground.

“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:

(a) Before the improvement or repair is started; or

(b) 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. (Ord. 128-88 § 2.0, 1988)

Article III. General Provisions

16.05.040 Lands to which this chapter applies.

This chapter shall apply to all areas of special flood hazards within the jurisdiction of the city of Hubbard, Oregon. (Ord. 128-88 § 3.1, 1988)

16.05.050 Basis for establishing the areas of special flood hazard.

The areas of special flood hazard identified by the Federal Insurance Administration in a scientific and engineering report entitled “The Flood Insurance Study for the City of Hubbard,” dated February 5, 1986, with the accompanying flood insurance maps, are hereby adopted by reference and declared to be a part of this chapter. The flood insurance study is on file at the Hubbard City Hall, 3720 Second Street – Hubbard, Oregon 97032. (Ord. 128-88 § 3.2, 1988)

Article IV. Administration

16.05.060 Development permit required.

A development permit shall be obtained before construction or development begins within any area of special flood hazard established in HMC 16.05.050. The permit shall be for all structures including manufactured homes, as set forth in HMC 16.05.030, and for all development including fill and other activities, also as set forth in HMC 16.05.030. (Ord. 128-88 § 4.1, 1988)

16.05.070 Designation of the city administrator or designee.

The city administrator or designee is hereby appointed to administer and implement this chapter by granting or denying development permit applications in accordance with its provisions. (Ord. 128-88 § 4.2, 1988)

16.05.080 Duties and responsibilities of the city administrator or designee.

Duties of the city administrator or designee shall include, but not be limited to:

(1) Permit Review.

(a) Review all development permits to determine that the permit requirements of this chapter have been satisfied;

(b) Review all development permits to determine that all necessary permits have been obtained from those federal, state, or local governmental agencies from which prior approval is required;

(c) 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 HMC 16.05.110(1) are met.

(2) Use of Other Base Flood Data. When base flood elevation data has not been provided in accordance with HMC 16.05.050, basis for establishing the areas of special flood hazard, the city administrator or designee shall obtain, review, and reasonably utilize any base flood elevation and floodway data available from a federal, state or other source, in order to administer HMC 16.05.100, specific standards, and HMC 16.05.110, floodways.

(3) Information to Be Obtained and Maintained.

(a) Where base flood elevation data is provided through the flood insurance study or required as in subsection (2) of this section, obtain and record 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 flood-proofed structures:

(i) Verify and record the actual elevation (in relation to mean sea level), and

(ii) Maintain the floodproofing certifications required in HMC 16.05.080(3)(c).

(c) Maintain for public inspection all records pertaining to the provisions of this chapter.

(4) Alteration of Watercourses.

(a) 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.

(b) Require that maintenance is provided within the altered or relocated portion of said watercourse so that the flood-carrying capacity is not diminished.

(5) Interpretation of FIRM Boundaries. Make interpretations, where needed, as to exact location of the boundaries of the areas of special flood hazards (for example, where there appears to be a conflict between a mapped boundary and actual field conditions). The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation. Such appeals shall be granted consistent with the standards of Section 60.6 of the rules and regulations of the National Flood Insurance Program (44 CFR 59-76). (Ord. 128-88 § 4.3, 1988)

Article V. Provisions for Flood
Hazard Reduction

16.05.090 General standards.

In all areas of special flood hazards, the following standards are required:

(1) Anchoring.

(a) All new construction and substantial improvements shall be anchored to prevent flotation, collapse, or lateral movement of the structure.

(b) All manufactured homes 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. (Reference FEMA’s “Manufactured Home Installation in Flood Hazard Areas” guidebook for additional techniques).

(2) Construction Materials and Methods.

(a) All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.

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

(c) 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.

(3) Utilities.

(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; and

(c) On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.

(4) Subdivision Proposals.

(a) All subdivision proposals shall be consistent with the need to minimize flood damage;

(b) All subdivision proposals shall have public utilities and facilities such as sewer, gas, electrical, and water systems located and constructed to minimize flood damage;

(c) All subdivision proposals shall have adequate drainage provided to reduce exposure to flood damage; and

(d) 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).

(5) Review of Building Permits. Where elevation data is not available either through the Flood Insurance Study or from another authoritative source (HMC 16.05.080(2)), applications for building permits shall be reviewed to assure that proposed construction will be reasonably safe from flooding. The test of reasonableness is a local judgement 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. (Ord. 128-88 § 5.1, 1988)

16.05.100 Specific standards.

In all areas of special flood hazards where base flood elevation data has been provided as set forth in HMC 16.05.050, basis for establishing the areas of special flood hazard, or HMC 16.05.080(2), use of other base flood data, the following provisions are required:

(1) Residential Construction.

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

(b) 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 flood waters. Designs for meeting this requirement must either be certified by a registered professional engineer or architect or must meet or exceed the following criteria:

(i) 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 shall be provided.

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

(iii) Openings may be equipped with screens, louvers, or other coverings or devices; provided, that they permit the automatic entry and exit of floodwaters.

(2) Nonresidential Construction. 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 of the base flood elevation; or, together with attendant utility and sanitary facilities, shall:

(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;

(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 subsection based on their development and/or review of the structural design, specifications and plans. Such certifications shall be provided to the official as set forth in HMC 16.05.080(3)(b);

(d) Nonresidential structures that are elevated, not floodproofed, must meet the same standards for space below the lowest floor as described in HMC 16.05.100(1)(b);

(e) Applicants floodproofing nonresidential 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 constructed to the base flood level will be rated as one foot below that level).

(3) Manufactured Homes. All manufactured homes to be placed or substantially improved within Zones A1-30, AH, and AE shall be elevated on a permanent foundation such that the lowest floor of the manufactured home is at or above the base flood elevation and be securely anchored to an adequately anchored foundation system in accordance with the provisions of HMC 16.05.090(1). (Ord. 128-88 § 5.2, 1988)

16.05.110 Floodways.

Located within areas of special flood hazard established in HMC 16.05.050 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:

(1) Prohibit encroachments, including fill, new construction, substantial improvements, and other development, unless certification by a registered professional engineer or architect is provided demonstrating that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge.

(2) If subsection (1) of this section is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of Article V of this chapter, provisions for flood hazard reduction. (Ord. 128-88 § 5.3, 1988)