For the purposes of this chapter, the following terms and phrases shall have the meanings adopted, unless the context clearly requires another signification:
APPEAL: A request for a review by the village manager for an interpretation of any floodplain provision of this chapter to be finally determined by the village board.
AREA OF SPECIAL FLOOD HAZARD: The land within the floodplain which is subject to one percent (1%) chance of flooding annually. This area may also be identified as that which is subject to the 100-year flood.
BASE FLOOD: A flood having a one percent (1%) chance of being equaled or exceeded in any given year. Also known as the 100-year flood.
BASE FLOOD ELEVATION: The elevation at all locations at which there is a one percent (1%) chance of annual flood occurrence. This elevation for special flood hazard areas of Buffalo Creek and North Flint Creek shall be as delineated by the 100-year flood profiles in the flood insurance study of the village prepared by the U.S. department of agriculture soil conservation services and published by FEMA.
BUILDING: A structure that is principally aboveground and is enclosed by walls and a roof. The term includes a gas or liquid storage tank.
BYPASS CHANNEL: A channel formed in the topography of the surface of the earth which functions as a duct to carry storm and flood water runoff through or around a specific area.
COMPENSATORY STORAGE: An artificially excavated volume of storage within a floodplain 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.
CONTROL STRUCTURE: Any structure designed to control the volume of storm or flood water runoff that passes through such structure during a specific measurable period of time.
DEVELOPMENT: The construction, reconstruction or alteration of any building or structure; or the construction, reconstruction or any alteration of any portion of or addition to any building or structure; or the storage of materials; or the preparation and recording of a plat of subdivision in accordance with applicable law; or some other change made to land, including paving, excavation, filling, dredging, mining, or substantial improvements on a given site, whether or not in connection with a proposed building or structure. Also included is the installation of a manufactured home on a site, preparing a site for a manufactured home or installing a travel trailer on a site for more than one hundred eighty (180) days.
DRY BOTTOM STORM OR FLOOD WATER STORAGE AREA: A natural or artificial stormwater storage area that is designed and maintained temporarily to contain water only when excess stormwater runoff occurs.
EXCESS STORMWATER RUNOFF: That portion of a volume of stormwater runoff that exceeds the safe storm drainage capacity of storm sewers or natural drainage channels serving a specified watershed.
FPE OR FLOOD PROTECTION ELEVATION: The elevation of the base flood (plus 1 foot) at any given location in the SFHA.
FLOOD: The condition existing when the waters of any river, stream, creek, watercourse, lake or pond temporarily rise to a height above their normal levels and overflow the boundaries within which they are ordinarily contained.
FLOOD FREQUENCY: A period of years during which a flood of a stated magnitude will be expected to occur once on the average.
FLOOD INSURANCE STUDY: The official report prepared by the federal insurance administration, including flood profiles, the flood boundary and floodway map and water surface elevations of the base flood.
FLOOD OF RECORD: An actual historical flood event for which sufficient records are available to establish its extent. No uniform probability of occurrence is associated with floods of record; however, the probability of occurrence may be determined for the event at specific locations.
FLOOD PROFILE: Graphical representations of the elevation of the water surface of the 100-year flood along the watercourses of the village.
FLOODPLAIN: The special flood hazard lands adjoining a watercourse whose surface elevation is lower than the base flood elevation and which are subject to periodic inundation during floods.
FLOODPROOFING: Modifications to structures made to reduce flood damages by making walls substantially watertight and having structural components with the capability of resisting hydrostatic and hydrodynamic loads and the effects of buoyancy. These changes may be made to existing, or incorporated in the design of new, structures.
FLOODWAY: The channel of a watercourse and those portions of the adjoining floodplains of which are reasonably required to carry and discharge the 100-year flood with no significant rise in the base flood elevation. Any floodway not delineated on the flood boundary and floodway map prepared by federal emergency management agency for the area shall be according to the best data available to the Illinois state water survey floodplain information repository.
FLOODWAY BOUNDARY AND FLOODWAY MAP AND FLOOD INSURANCE RATE MAP (FIRM): Official maps of the village, issued or approved by the administrator of the federal insurance administration, on which the boundaries of the floodway have been delineated and the areas of special flood hazard delineated.
FLOODWAY ENCROACHMENT LINES: The lateral boundaries of the floodway which separate it from the floodway fringes.
FLOODWAY FRINGE: The higher portion of the floodplain, immediately adjacent to and on either side of the floodway occupied by quiescent or slow moving waters during floods.
FREEBOARD: An increment of elevation added to the base flood elevation to provide a factor of safety for uncertainty in calculations, unknown localized conditions, wave actions and unpredictable effects such as may be caused by ice or debris jams.
GROUNDWATER RECHARGE: An artificial or natural process of replenishing natural underground water supplies.
HIGH WATER ELEVATION: The elevation of floodwaters of the 100-year flood at any given point.
HYDROSTATIC UPLIFT: The upward pressure exerted on floor slabs or an entire structure by standing water or groundwater which tends to float a structure or crack the floor. It is measured by the difference in elevation between the surface under pressure and the surface level of the water. Hydrostatic pressure may also be horizontal, imposing forces on walls causing them to crack or fail.
NATURAL DRAINAGE: The drainage of water through channels or other watercourses formed or occurring in the existing surface topography of the earth prior to changes made by artificial causes.
100-YEAR FLOOD AND 100-YEAR RAIN: A flood magnitude with a one percent (1%) statistical chance of being equaled or exceeded during any year. A flood this large would be reached once during a one hundred (100) year period, on the average. However, the occurrence of such an event does not diminish the chance of its recurring again at any time. The same conditions apply to determining the magnitude and frequency of the 100-year rain.
RETENTION STORAGE AREA: Same as storm or flood water storage area herein.
SFHA OR SPECIAL FLOOD HAZARD AREA: Those lands within the jurisdiction of the village that are subject to inundation by the base flood. The SFHAs of the village are generally identified as such on the flood insurance rate map of the village prepared by United States department of agriculture, soil and conservation service dated July 5, 1983, and as delineated by federal emergency management agency in the flood insurance study dated January 5, 1983, and flood insurance rate map, dated November 3, 1982.
SAFE STORM DRAINAGE CAPACITY: The quantity of stormwater runoff that can be transported by a channel or conduit without having the water surface rise above the top of such channel or conduit.
STORMWATER STORAGE AREA: Areas that naturally or artificially serve to store excess stormwater.
SUBSTANTIAL IMPROVEMENT: Any repair, reconstruction or improvement of a structure, the cost of which equals or exceed 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 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. 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 structure listed on the national register of historic places or a state inventory of historic places.
TRIBUTARY WATERSHED: All of the area that contributes stormwater runoff to a given point.
VARIANCE: A grant of relief from the floodplain requirements of this chapter permitting construction otherwise prohibited.
VILLAGE: The village of Lake Zurich, Lake County, Illinois.
WATERCOURSE: Any stream, creek, branch, tributary, natural or artificial depression, slough, gulch, reservoir, lake, pond or natural or manmade drainageway in or into which stormwater runoff and floodwaters flow either regularly or intermittently.
WET BOTTOM STORMWATER STORAGE AREA: A stormwater storage area that is designed and maintained temporarily to contain water only when excess stormwater runoff occurs and permanently to hold an additional volume of water at a level which is at or below the discharge structure of such storage area.
WETLANDS: The land areas in which the groundwater table or zone of saturation periodically intersects the surface and which contain wetland plant species that are listed in Norman C. Fasscett, "A Manual Of Aquatic Plants" (Madison: University Of Wisconsin Press, 1957) and/or Floyd Swink, "Plants Of The Chicago Region", second edition (Lisle, Illinois, the Morton Arboretum, 1974) and/or Henry A. Gleason, "The New Britton And Brown Illustrated Flora Of The Northeastern United States And Adjacent Canada" (New York: Hafner Press, 1952). (Ord. 1114-83, 5-2-1983; amd. Ord. 88-02-257, 2-15-1988; Ord. 2012-10-861, 10-1-2012)