For the purpose of this chapter, the following definitions shall apply unless the context clearly indicates or requires a different meaning.
ARMORING. A form of channel modification which involves the placement of materials (concrete, riprap, bulkheads and the like) within a stream channel or along a shore line to protect property above streams, lakes and ponds from erosion and wave damage caused by wave action and stream flow.
BULKHEAD. A retaining wall that protects property along water.
CHANNEL. A natural or artificial watercourse of perceptible extent that periodically or continuously contains moving water, or which forms a connecting link between two bodies of water. It has a definite bed and banks that serve to contain the water.
CHANNEL MODIFICATION or CHANNELIZATION. To alter a watercourse by changing the physical dimension or materials of the channel. CHANNEL MODIFICATION includes damming, riprapping (or other armoring), widening, deepening, straightening, relocating, lining and significant removal of bottom or woody vegetation. CHANNEL MODIFICATION does not include the clearing of debris or trash from the watercourse. CHANNELIZATION 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).
CONTROL STRUCTURE. A structure designed to control the rate of storm water runoff that passes through the structure, given a specific upstream and downstream water surface elevation.
CULVERT. A structure designed to carry drainage water or small streams below barriers such as roads, driveways or railway embankments.
DEPRESSIONAL AREA. Any area which is lower in elevation on all sides than surrounding properties (i.e. does not drain freely), or whose drainage is severely limited such as by a restrictive culvert. A DEPRESSIONAL area will fill with water on occasion when runoff into it exceeds the rate of infiltration into underlying soil or exceeds the discharge through its controlled outlet. Large DEPRESSIONAL areas may provide significant storm water or floodplain storage.
DEVELOPMENT. The carrying out of any building, agricultural or mining operation, or the making of any change in the use or appearance of land, and the dividing of land into two or more parcels. The following activities or uses shall constitute, for the purposes of this subchapter, to involve development as defined herein:
(1) Any construction, reconstruction or alteration of a structure to occupy more or less ground area or the onsite preparation for same;
(2) Any change in the intensity of use of land, such as an increase in the number of dwelling units on land, or a material increase in the site coverage of businesses, manufacturing establishments, offices, and dwelling units, including mobile homes, campers and recreational vehicles, on land;
(3) Any agricultural use of land including, but not limited to, the use of land in horticulture, floriculture, forestry, dairy, livestock, poultry, beekeeping, pisciculture and all forms of farm products and farm production;
(4) The commencement of drilling, except to obtain soil samples, or the commencement of mining, filling, excavation, dredging, grading or other alterations of the topography;
(5) Demolition of a structure or redevelopment of a site;
(6) Clearing of land as an adjunct of construction for agricultural, private residential, commercial or industrial use;
(7) Deposit of refuse, solid or liquid waste, or fill on a parcel of land, or the storage of materials;
(8) Construction, excavation or fill operations relating to the creation or modification of any road, street, parking facility or any drainage canal, or to the installation of utilities or any other grading activity that alters the existing topography;
(9) Construction or erection of dams, levees, walls, fences, bridges or culverts; and
(10) Any other activity that might change the direction, height or velocity of flood or surface waters.
EROSION. The general process whereby soils are moved by flowing water or wave action.
FILTERED VIEW. The maintenance or establishment of woody vegetation of sufficient density to screen developments from a stream or wet land, to provide for streambank stabilization and erosion control, to serve as an aid to infiltration of surface runoff, and to provide cover to shade the water. The vegetation need not be so dense as to completely block the view. FILTERED VIEW means no clear cutting.
FLOODPLAIN. The land adjacent to a body of water with ground surface elevations at or below the 100-year frequency flood elevation.
FLOODWAY. The portion of the floodplain (sometimes referred to as the base floodplain or special flood hazard area) required to store and convey the base flood. The FLOODWAY is the 100-year floodway as designated and regulated by the State Department of Transportation/Division of Water Resources. The remainder of the floodplain which is outside the regulatory floodway is referred to as the flood fringe or floodway fringe.
HYDRAULIC CHARACTERISTICS. The features of a watercourse which determine its water conveyance capacity. These features include but are not limited to: size and configuration of the cross-section of the watercourse and floodway; texture and roughness of materials along the watercourse; alignment of watercourse; gradient of watercourse; amount and type of vegetation within the watercourse; and size, configuration and other characteristics of structures within the watercourse. In low-lying area, the characteristics of the overbank area also determine water conveyance capacity.
LAKE or POND. Any inland waterbody, fed by spring or surface water flow.
LOT. An area of land, with defined boundaries, that is designated in official assessor’s records as being one parcel.
NATURAL. In reference to watercourses, those stream channels, grassed waterways and swales formed by the existing surface topography of the earth prior to changes made by unnatural causes. 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 alteration of the course or cross-section of the stream caused by filling or excavating.
ORDINARY HIGH WATER MARK (OHWM). The point on the bank or shore up to which the presence and action of surface water is so continuous so 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.
QUALIFIED PROFESSIONAL. A person trained in one or more of the disciplines of biology, geology, soil science, engineering or hydrology whose training and experience ensure a competent analysis and assessment of stream, lake, pond and wetland conditions and impacts.
REGISTERED PROFESSIONAL ENGINEER. A professional engineer registered under the provisions of The Illinois Professional Engineering Act, being ILCS Ch. 225, Act 325, §§ 1 et seq. and any act amendatory thereof.
RETENTION/DETENTION FACILITY. A facility that provides for storage of storm water runoff and controlled release of this runoff during and after a flood or storm.
RUNOFF. The portion of precipitation on the land that is not absorbed by the soil or plant material and which runs off the land.
SEDIMENTATION. The processes that deposit soils, debris and other materials either on other ground surfaces or in water bodies or watercourses.
SETBACK. The horizontal distance between any portion of a structure or any development activity and the ordinary high water mark of a perennial or intermittent stream, the ordinary high water mark of a lake or pond, or the edge of a wetland, measured from the structure’s or development’s closest point to the ordinary high water mark, or edge.
STREAM. A body of running water flowing continuously or intermittently in a channel on or below the surface of the ground. Seven and one-half minute topographic maps of the U.S. Geological Survey are one reference for identifying perennial and intermittent streams. For purposes of this chapter, the term STREAM does not include storm sewers.
STRUCTURE. Anything that is constructed, erected or moved to or from any premise which is located above, on or below the ground including, but not limited to roads, signs, billboards and mobile homes. Temporary recreational facilities including, but not limited to, tents, camper trailers and recreation vehicles are not considered STRUCTURES when used less than 180 days per year and located landward of the minimum setback provided as a natural vegetation strip.
VEGETATION. All plant growth, especially trees, shrubs, mosses and grasses.
WATERCOURSE. Any river, stream, creek, brook, branch, natural or artificial depression, ponded area, slough, gulch, draw, ditch, channel, conduit, culvert, swale, grass waterway, gully, ravine, wash, or natural or human-made drainageway, which has a definite channel, bed and banks, in or into which storm water runoff and floodwater flow either regularly or intermittently.
WETLAND. Those transitional lands between terrestrial and aquatic system where the water table is usually at or near the surface or the land is covered by shallow water. Classification of areas as WETLANDS shall follow the Classification of Wetlands and Deepwater Habitats of the United States as published by the U.S. Fish and Wildlife Service (FWS/OBS-79/31).
(Ord. 570, passed 12-7-1988)