Chapter 14.08
DEFINITIONS
Sections:
14.08.010 Definitions.
For the purposes of this title, the following definitions are adopted:
“Accessory structure” means a nonhabitable structure which is on the same parcel of property as the principal structure to be insured and the use of which is incidental to the use of the principal structure.
“Act” means an act in relation to the regulation of the rivers, lakes and streams of the state of Illinois, 615 ILCS 5/5 et seq.
“Applicant” means any person, firm, corporation or agency which submits an application.
“Appropriate use” means only uses of the designated floodway that are permissible and will be considered for permit issuance. The only uses that will be allowed are as specified in RMC 14.28.030.
“Base flood” means the flood having a one percent chance of being equaled or exceeded in any given year. The base flood is also known as the one-hundred-year frequency flood event. Application of the base flood elevation at any location is as defined in RMC 14.20.010.
“Base flood elevation (BFE)” means the elevation in relation to mean sea level of the crest of the base flood.
“Basement” means that portion of the building having its floor subgrade (below ground level) on all sides.
“Building” means a walled and roofed structure, including gas or liquid storage tank, that is principally above ground, including manufactured homes, prefabricated buildings, and gas or liquid storage tanks. The term also includes recreational vehicles and travel trailers installed on a site for more than one hundred eighty days per year.
“Channel” means any river, stream, creek, brook, branch, natural or artificial depression, ponded area, flowage, slough, ditch, conduit, culvert, gully, ravine, wash, or natural or manmade drainage way, which has a definite bed and banks or shoreline, in or into which surface or groundwater flows, either perennially or intermittently.
“Channel modification” means alteration of a channel by changing the physical dimensions or materials of its bed or banks. Channel modification includes damming, rip-rapping (or other armoring), widening, deepening, straightening, relocating, lining and significant removal of native vegetation from the bottom or banks. Channel modification does not include the clearing of dead or dying vegetation, debris, or trash from the channel. Canalization is a severe form of channel modification involving a significant change in the channel cross-section and typically involving relocation of the existing channel (e.g., straightening).
“Compensatory storage” means an artificially excavated, hydraulically equivalent volume of storage within the SFHA used to balance the loss of natural flood storage capacity when artificial fill or structures are placed within the floodplain. The uncompensated loss of natural floodplain storage can increase off-site floodwater elevations and flows.
“Conditional approval of a designated floodway map change” means preconstruction approval by IDNR/OWR and FEMA of a proposed change to the floodway map. This preconstruction approval, pursuant to this title, gives assurances to the property owner that once an appropriate use is constructed according to permitted plans, the floodway map can be changed, as previously agreed, upon review and acceptance of as-built plans.
“Conditional letter of map revision (CLOMR)” means a letter which indicates that FEMA will revise base flood elevations, flood insurance rate zones, flood boundaries or floodway as shown on an effective flood hazard boundary map or flood insurance rate map, once the as-built plans are submitted and approved.
“Control structure” means a structure designed to control the rate of flow that passes through the structure, given a specific upstream and downstream water surface elevation.
“Critical facility” means any facility which is critical to the health and welfare of the population and, if flooded, would create an added dimension to the disaster. Damage to these critical facilities can impact the delivery of vital services, can cause greater damage to other sectors of the community, or can put special populations at risk. Examples of critical facilities where flood protection should be required include: emergency services facilities (such as fire and police stations), schools, hospitals, retirement homes and senior care facilities, major roads and bridges, critical utility sites (telephone switching stations or electrical transformers), and hazardous material storage facilities (chemicals, petrochemicals, hazardous or toxic substances). Examples of critical facilities where flood protection is recommended include: sewage treatment plants, water treatment plants, and pumping stations.
“Dam” means all obstructions, wall embankments or barriers, together with their abutments and appurtenant works, if any, constructed for the purpose of storing or diverting water or creating a pool. Dams may also include weirs, restrictive culverts or impoundment structures. Underground water storage tanks are not included.
“Designated floodway” means the channel, including on-stream lakes, and that portion of the floodplain adjacent to a stream or watercourse, generally depicted on the FEMA FIRM map, which is needed to store and convey the existing one-hundred-year frequency flood discharge with no more than a one-tenth-foot increase in stage due to the loss of flood conveyance or storage, and no more than a ten percent increase in velocities.
1. The floodways are designated on the countywide flood insurance rate map of Cook County prepared by FEMA and dated August 19, 2008. When two floodway maps exist for a waterway, the more restrictive floodway limit shall prevail.
2. The floodways for those parts of unincorporated Cook County that are within the extraterritorial jurisdiction of the village that may be annexed into the village are designated for Little Calumet River and Cal Sag Channel on the countywide flood insurance rate map prepared by FEMA and dated August 19, 2008.
3. To locate the designated floodway boundary on any site, the designated floodway boundary should be scaled off the designated floodway map and located on a site plan, using reference marks common to both maps. Where interpretation is needed to determine the exact location of the designated floodway boundary, IDNR/OWR should be contacted for the interpretation.
“Development” means any manmade change to real estate, including:
1. Construction, reconstruction, repair, or placement of a building or any addition to a building.
2. Installing a manufactured home on a site, preparing a site for a manufactured home, or installing a travel trailer or recreational vehicle on a site for more than one hundred eighty days. If the travel trailer or recreational vehicle is on site for more than one hundred eighty days, it must be fully licensed and ready for highway use.
3. Drilling, mining, installing utilities, construction of roads, bridges, or similar projects.
4. Demolition of a structure or redevelopment of a site.
5. Clearing of land as an adjunct of construction.
6. Construction or erection of levees, walls, fences, dams, or culverts; channel modification; filling, dredging, grading, excavating, paving, or other nonagricultural alterations of the ground surface; storage of materials; deposit of solid or liquid waste.
7. Any other activity of man that might change the direction, height, or velocity of flood or surface water, including extensive vegetation removal.
8. Substantial improvement of an existing building.
Development does not include routine maintenance of existing buildings and facilities such as reroofing or resurfacing of roads when there is no increase in elevation, or gardening, plowing, and similar agricultural practices that do not involve filling, grading, or construction of levees.
“Elevation certificates” means a form published by FEMA that is used to certify the elevation to which a building has been elevated.
“Erosion” means the general process whereby soils are moved by flowing water or wave action.
“Exempt organizations” means organizations which are exempt from this title per Illinois Compiled Statutes (ILCS) including state, federal or local units of government.
“Existing manufactured home park or subdivision” means a manufactured home park or subdivision for which the construction of facilities for servicing the lots on which the manufactured homes are to be affixed (including, at a minimum, the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads) has been completed before April 1, 1990.
“Expansion to an existing manufactured home park or subdivision” means the preparation of additional sites by the construction of facilities for servicing the lots on which the manufactured homes are to be affixed (including the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads).
“FEMA” means Federal Emergency Management Agency and its regulations at 44 CFR 59 through 79, as amended.
“Flood” means a general and temporary condition of partial or complete inundation of normally dry land areas from overflow of inland or tidal waves, or the unusual and rapid accumulation or runoff of surface waters from any source.
“Flood frequency” means a period of years, based on a statistical analysis, during which a flood of a stated magnitude may be expected to be equaled or exceeded.
“Flood fringe” means that portion of the floodplain outside of the designated floodway. See commentary on “designated floodway.”
“Flood insurance rate maps (FIRM)” means a map prepared by FEMA that depicts the special flood hazard area (SFHA) within a community. This map includes insurance rate zones and floodplains and may or may not depict floodways.
“Flood insurance study” means an examination, evaluation and determination of flood hazards and if appropriate, corresponding water surface elevations.
“Floodplain” means that land typically adjacent to a body of water with ground surface elevations at or below the base flood or the one-hundred-year frequency flood elevation. Floodplains may also include detached special flood hazard areas, ponding areas, etc. The floodplain is also known as the special flood hazard area (SFHA).
1. The floodplains are those lands within the jurisdiction of the village that are subject to inundation by the base flood or one-hundred-year frequency flood. The SFHAs of the village are generally identified as such on panel number(s) 0643J, 0644J, 0645J, 0661J and 0663J of the countywide flood insurance rate map of the Village prepared by the Federal Emergency Management Agency and dated August 19, 2008.
2. The SFHAs of those parts of unincorporated Cook County that are within the extraterritorial jurisdiction of the village or that may be annexed into the village are generally identified as such on panel number(s) 0643J, 0644J, 0645J, 0661J and 0663J of the countywide flood insurance rate map prepared for Cook County by the Federal Emergency Management Agency and dated August 19, 2008.
“Floodproofing” means any combination of structural and nonstructural additions, changes or adjustments to structures which reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures and their contents.
“Floodproofing certificate” means a form published by FEMA that is used to certify that a building has been designed and constructed to be structurally dry floodproofed to the flood protection elevation.
“Flood protection elevation (FPE)” means the elevation of the base flood or one-hundred-year frequency floods plus one foot of freeboard at any given location in the SFHA.
Floodway. See “Designated floodway.”
“Historic structure” means any structure that is:
1. Listed individually in the National Register of Historic Places 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 historic district or a district preliminarily determined by the Secretary to qualify as a registered historic district;
3. Individually listed on the State Inventory of Historic Places by the Illinois Historic Preservation Agency;
4. Individually listed on a local inventory of historic places that has been certified by the Illinois Historic Preservation Agency.
“Hydrologic and hydraulic calculations” means engineering analysis which determine expected flood flows and flood elevations based on land characteristics and rainfall events.
“IDNR/OWR” means Illinois Department of Natural Resources, Office of Water Resources.
“Letter of map amendment (LOMA)” means an official determination by FEMA that a specific structure is not in a one-hundred-year floodplain; amends the FIRM.
“Letter of map revision (LOMR)” means a letter that revises base flood or one-hundred-year frequency flood elevations, floodplains or floodways as shown on an effective FIRM.
“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 title.
“Manufactured home” means a structure, transportable in one or more sections, which is built on a permanent chassis and is designated for use with or without a permanent foundation when attached to the required utilities. The term “manufactured home” also includes park trailers, travel trailers and other similar vehicles placed on site for more than one hundred eighty consecutive days. The term “manufactured home” does not include a “recreational vehicle.”
“Manufactured home park or subdivision” means a parcel (or contiguous parcels) of land divided into two or more manufactured home lots for rent or sale.
“Mitigation” includes those measures necessary to minimize the negative effects which floodplain development activities might have on the public health, safety and welfare. Examples of mitigation include: excavation of compensatory storage, soil erosion and sedimentation control, and channel restoration. Mitigation may also include those activities taken to reduce a structure’s susceptibility to flooding.
“Natural,” when used in reference to channels, means those channels formed by the existing surface topography of the earth prior to changes made by man. A natural stream tends to follow a meandering path; its floodplain is not constrained by levees; the area near the bank has not been cleared, mowed or cultivated; the stream flows over soil and geologic materials typical of the area with no substantial alteration of the course or cross-section of the stream caused by filling or excavating. A modified channel may regain some natural characteristics over time as the channel meanders and vegetation is reestablished. Similarly, a modified channel may be restored to more natural conditions by man through regrading and revegetation.
“NAVD 88” means National American Vertical Data of 1988. NAVD 88 supersedes the National Geodetic Vertical Datum of 1929 (NGVD).
“New construction” means structures for which the start of construction commenced on or after the effective date of a floodplain management regulation adopted by a community and includes any subsequent improvements to such structures.
“New manufactured home park or subdivision” means manufactured home park or subdivision for which the construction of facilities for servicing the lots on which the manufactured homes are to be affixed (including at a minimum, the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads) has been completed on or after April 1, 1990.
“Ordinary high water mark (OHWM)” means the point on the bank or shore up to which the presence and action of surface water is so continuous as to leave a distinctive mark such as by erosion, destruction or prevention of terrestrial vegetation, predominance of aquatic vegetation or other easily recognized characteristics.
“Public bodies of waters” means all open public streams and lakes capable of being navigated by watercraft, in whole or in part, for commercial uses and purposes, and all lakes, rivers, and streams which in their natural condition were capable of being improved and made navigable, or that are connected with or discharge their waters into navigable lakes or rivers within or upon the borders of the state of Illinois, together with all bayous, sloughs, backwaters, and submerged lands that are open to the main channel or body of water directly accessible thereto.
“Public flood control project” means a flood control project which will be operated and maintained by a public agency to reduce flood damages to existing buildings and structures, including a hydrologic and hydraulic study of the existing and proposed conditions of the watershed. Nothing in this definition shall preclude the design, engineering, construction or financing, in whole or in part, of a flood control project by persons or parties who are not public agencies.
“Recreational vehicle” or “travel trailer” means a vehicle which is:
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.
“Regional permits” are offered for preapproved projects which are considered minor projects that are permissible per IDNR/OWR Part 3708 rules for northeastern Illinois regulatory floodways. A complete listing of the terms and conditions for specific project types can be obtained from the IDNR/OWR website.
“Registered land surveyor” means a land surveyor registered in the state of Illinois under the Illinois Land Surveyors Act. (225 ILCS 330/1, et seq.)
“Registered or licensed professional engineer” means an engineer registered in the state of Illinois under the Illinois Professional Engineering Practice Act. (225 ILCS 325/1 et seq.)
“Repair, remodeling or maintenance” means development activities which do not result in any increases in the outside dimensions of a building or any changes to the dimensions of a structure.
“Repetitive loss” means flood-related damages sustained by a structure on two separate occasions during a ten-year period for which the cost of repairs at the time of each such flood event, on the average, equals or exceeds twenty-five percent of the market value of the structure before the damaged occurred.
Retention/Detention Facility. A “retention facility” stores storm water runoff without a gravity release. A “detention facility” provides for storage of storm water runoff and controlled release of this runoff during and after a flood or storm.
“Riverine SFHA” means any SFHA subject to flooding from a river, creek, intermittent stream, ditch, on-stream lake system or any other identified channel. This term does not include areas subject to flooding from lakes, ponding areas, areas of sheet flow, or other areas not subject to overbank flooding.
“Runoff” means the water derived from melting snow or rain falling on the land surface, flowing over the surface of the ground or collected in channels or conduits.
“Sedimentation” means the processes that deposit soils, debris, and other materials either on other ground surfaces or in bodies of water or watercourses.
Special Flood Hazard Area (SFHA). See “Floodplain.”
“Start of construction” includes substantial improvement, and means the date the building permit was issued, provided the actual start of construction, repair, reconstruction, rehabilitation, addition placement, or other improvement was within one hundred eighty days of the permit date. The actual start means either the first placement of permanent construction of a structure on a site, such as the pouring of slab or footings, the installation of piles, the construction of columns, or any work beyond the stage of excavation; or placement of a manufactured home on a foundation.
“Statewide permits” are offered for preapproved projects that are considered minor projects which are permissible per the IDNR/OWR Part 3700 rules. A complete listing of the statewide permits and permit requirements can be obtained from the IDNR/OWR website.
Structure. See “Building.”
“Substantial damage” means damage of any origin sustained by a structure whereby the cumulative percentage of damage during the life of the building equals or exceeds fifty percent of the market value of the structure before the damage occurred regardless of actual repair work performed. Volunteer labor and materials must be included in this determination. The term includes repetitive loss buildings. See “Repetitive loss.”
“Substantial improvement” means any reconstruction, rehabilitation, addition, or improvement of a structure taking place during the life of the building in which the cumulative percentage of improvements equals or exceeds fifty percent of the market value of the structure before the improvement or repair is started.
1. “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 building. This term includes structures which have incurred repetitive loss or substantial damage, regardless of the actual work done.
2. The term does not, however, include either:
a. Any project for improvement of a structure 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 a “historic structure” listed on the National Register of Historic Places or the Illinois Register of Historic Places; provided, that the alteration will not preclude the structure’s continued designation as a historic structure.
“Transition section” means reaches of the stream or floodway where water flows from a narrow cross-section to a wide cross-section or vice versa.
“Village” means the village of Riverdale, Cook County, Illinois, an Illinois municipal corporation.
“Violation” means the failure of a structure or other development to be fully compliant with the community’s floodplain management regulations. A structure or other development without the elevation certificate, other certifications, or other evidence of compliance is presumed to be in violation until such time as that documentation is provided. (Ord. 2008-22 § 15.300, 2008)