(A) Statutory Authorization And Findings: The following flood plain regulations (hereafter in this Chapter referred to as "regulations") are hereby adopted pursuant to Section 31-15-103 Colorado Revised Statutes, as amended, in which authority has been delegated to local governments to adopt ordinances to promote the public health, safety and general welfare of its citizens, and by virtue of the City's home rule Charter. The City Council does hereby declare the following:
1. Certain areas of the City are subject to periodic flooding which may result in loss of life and property, health and safety hazards, disruption of business and governmental services, extraordinary public expense for flood protection and relief, and impairment of the tax base, all of which adversely affect the public health, safety and general welfare.
2. Flood losses are caused by the cumulative effect of obstructions in flood hazard areas which increase flood heights and velocities, and which may cause damage to property outside flood plains.
3. Some properties, located within flood plains, are inadequately floodproofed, elevated, or otherwise protected from flood damage, and may contribute to the flood losses.
(B) Statement Of Purpose: It is the purpose of these regulations to promote the public health, safety, and general welfare, and to minimize public and private losses due to flooding within the City by adopting provisions which are intended to:
1. Protect human life and health;
2. Minimize expenditures of public money for costly flood control projects;
3. Minimize the need for post-flood rescue and relief efforts which are, generally, undertaken at public expense;
4. Minimize prolonged business interruptions;
5. Minimize damage to public facilities and utilities which are located in flood plains, such as water and gas mains, electric, telephone and sewer lines, streets and bridges;
6. Maintain a stable tax base by providing for the sound use and development of flood plains which has minimum flood damage potential;
7. Ensure that information is available to potential buyers that property is in a flood plain;
and
8. Ensure that those who occupy flood plains know that they are responsible for their actions.
(C) Methods Of Reducing Flood Losses: In order to accomplish the intent of these regulations, one or more of the following safeguards may be required by the City as a condition to obtaining approval to develop in a flood plain. The City may:
1. Restrict or prohibit uses which are dangerous to health, safety, and property due to flooding or erosion hazards; or which cause greater flood heights and velocities;
2. Require that uses and associated facilities which are vulnerable to floods are adequately protected against flood damage at the time of initial construction;
3. Control alteration of natural floodplains, stream channels, and natural protective barriers, which convey or confine floodwaters;
4. Control filling, grading, dredging, and other development which may increase flood damage; and
5. Prevent or regulate the construction of barriers in floodplains which will divert floodwaters and increase flood hazards in other areas. (Revised 6-12-1992)
10-6-2 : DEFINITIONS:
Unless specifically defined below or elsewhere in this code, words or phrases used in these regulations shall be interpreted to have the same meaning as in common usage, and to provide reasonable application of these regulations.
APPEAL: A request for review, held by the city's planning commission, of the floodplain administrator's interpretation of any provision of these regulations.
AREA OF SHALLOW FLOODING: An area susceptible to base flood depths ranging from one foot (1') to three feet (3') usually designated zone AO or AH on the city's flood insurance rate map (FIRM) with a one percent (1%) or greater chance of flooding in any given year, where a clearly defined channel does not exist, the path of flooding is unpredictable and indeterminate, and velocity flow may be evident. Such flooding is characterized by ponding or sheet flow.
AREA OF SPECIAL FLOOD HAZARD: Land within the floodplain subject to a one percent (1%) or greater chance of flooding in any given year. The area may be designated zone A, AE, AH, AO, or A99 on the city's flood insurance rate map (FIRM).
BASE FLOOD: A flood having a one percent (1%) chance of being equaled or exceeded in any given year. Sometimes also known as a "100-year flood".
CHANNEL: A perceptible natural or artificial watercourse, with a definite bed and banks to confine and conduct continuous or intermittent water flows.
COMMISSION: The Littleton city planning commission, which is a duly appointed body of the city council created under Title 2 of this code.
CRITICAL FACILITY: A structure or related infrastructure, but not the land on which it is situated, that if flooded may result in significant hazards to the public health and safety or interrupt essential services and operations for the community at any time before, during and after a flood.
DEVELOPMENT: Any manmade change to improved or unimproved real property located within a floodplain including, but not limited to, buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations.
EXISTING MANUFACTURED HOME PARK: A manufactured home park, for which construction is complete, including installation of utilities, final site grading, or pouring of concrete pads, prior to July 18, 1978.
EXPANSION OF EXISTING MANUFACTURED HOME PARK: The construction of additional lots by the installation of facilities necessary for serving the units to be placed on such lots including the installation of utilities, the construction of streets, final site grading, or the pouring of concrete pads.
FEMA: Federal emergency management agency.
FLOOD: A general and temporary condition of partial or complete inundation of normally dry land areas from:
( ) The overflow of inland waters; and/or
( B) The unusual and rapid accumulation or runoff of surface waters from any source.
FLOOD INSURANCE RATE MAP (FIRM): The official map on which FEMA has delineated floodplains and the risk premium zones applicable to the city.
FLOOD INSURANCE STUDY: The official report, entitled "The Flood Insurance Study For Arapahoe County And Incorporated Areas", provided by FEMA, that includes flood profiles, the flood boundary/floodway map, and the water surface elevation of the base flood. The flood insurance study referred to in these regulations is the study dated December 17, 2010, or as may be revised.
FLOOD PROFILE: A graph of the longitudinal profile of a watercourse which shows the water surface elevation of a flood at various locations.
FLOOD PROTECTION ELEVATION: An elevation of one foot (1') above the water surface elevation of a base flood under existing channel and floodplain conditions, as established for a specific parcel of land.
FLOOD STORAGE AREA: The fringe portion of a floodplain in which flows are characteristically shallow and of low velocities.
FLOODPLAIN: The relatively flat or lowland area adjoining a river, watercourse, lake, or other body of surface water, which has been or may be temporarily covered by floodwater. For administrative purposes, the floodplain is also defined as the land area inundated by the base flood as defined in the flood insurance study, or by other recognized sources.
FLOODPLAIN ADMINISTRATOR (ADMINISTRATOR): The city manager or a designated representative.
FLOODPROOFING: Any combination of structural or nonstructural additions, changes or adjustments which are intended to reduce or eliminate the risk of flood damage to property, utilities, structures and their contents.
FLOODWAY: That portion of a floodplain that must be reserved in order to discharge the base flood without a cumulative increase in the water surface elevation more than one-half foot (0.5') for newly studied reaches or due to new development. Previously studied reaches and letters of map revisions to existing floodway delineations may continue to use the floodway criteria in place at the time of the existing floodway delineation.
HIGHEST ADJACENT GRADE: The highest natural elevation of the ground surface prior to construction next to the proposed walls of a structure.
HISTORIC STRUCTURE: Any structure that:
(A) Is listed on the national register of historic places or by the Colorado Historical Society, or
(B) Has been certified to contribute to the historical significance of a registered historical district.
( C) Is individually listed on a local inventory of structures of historical merit.
LOWEST FLOOR: The lowest floor of the lowest enclosed area (including basements).
Enclosures in areas other than basements and which are used solely for parking, building access, or storage, are not to be considered in determining a building's lowest floor, provided that such enclosures do not violate the applicable requirements of these regulations.
MANUFACTURED HOME: 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 occupancy. The term "manufactured home" does not include recreational vehicles.
MANUFACTURED HOME PARK OR SUBDIVISION: A parcel (or contiguous parcels) of land divided into two (2) or more manufactured home lots for rent or sale.
NEW CONSTRUCTION: Development for which the "start of construction" commenced on or after July 18, 1978.
NEW MANUFACTURED HOME PARK: A manufactured home park which is constructed, including the installation of utilities, construction of streets, and final site grading, or pouring of concrete pads, after July 18, 1978.
OTHER FLOOD AREAS: Areas of two-tenths percent (0.2%) annual chance flood, areas of one percent (1%) annual chance flood with average depths of less than one foot (1'), or with drainage areas less than one square mile. The area may be designated zone X on the city's flood insurance rate map (FIRM).
RECREATIONAL VEHICLE: A vehicle, built on a single chassis, which is four hundred (400) square feet or less when measured at the largest horizontal projections, which is not intended for permanent use as a dwelling, and is designed to be self-propelled or to be towed by an automobile or light truck, and designed primarily not for use as a permanent dwelling but as temporary living quarters for recreation, camping, travel or seasonal use.
SPECIAL EXCEPTION: A use which may be permitted in a floodplain upon approval by the commission, and to which the commission may attach specific performance requirements.
START OF CONSTRUCTION: The actual start of construction, i.e., 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 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 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: A walled and roofed building that is principally above ground, including manufactured homes.
SUBSTANTIAL DAMAGE: Damage, of any origin, sustained by a structure which results in costs to restore the structure to its original condition that equal or exceed fifty percent (50%) of the market value of the structure before the damage occurred.
SUBSTANTIAL IMPROVEMENT: Any repair, reconstruction, or improvement to a structure, the cost of which equals or exceeds fifty percent (50%) 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 purpose 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. "Substantial improvement" does not include either: a) any construction necessary to comply with existing state or local health, sanitary, or safety code specifications which are solely necessary to assure safe living conditions, or b) any alteration of any officially designated historic structure.
VARIANCE: A grant of relief from the requirements of these regulations by the commission which permits construction within a floodplain in a manner that would otherwise be prohibited.
VIOLATION: The failure of a structure or other development to be fully compliant with the city's floodplain regulations. A structure or other development where start of construction commenced on or after July 18, 1978, without an elevation certificate, other certifications or other evidence of compliance, is presumed to be in violation until such time as that documentation is provided.
WATER SURFACE ELEVATION DATA: The elevation, in relation to mean sea level, expected to be reached by floods of various magnitudes and frequencies at pertinent points along a watercourse.
WATERCOURSE: A channel, natural depression, slough, artificial channel, gulch, arroyo, stream, creek, pond, reservoir, or lake into which storm runoff and floodwater flows either regularly or infrequently. This includes major drainageways for carrying urban storm runoff. (Revised 6-12-1992; amd. Ord. 25, Series of 2010; Ord. 19, Series of 2012; Ord. 38, Series of 2013; Ord. 15, Series of
2016)