Drainage area means a geographic area within which stormwater, sediments, or dissolved materials drain to a particular receiving waterbody or to a particular point along a receiving waterbody.
Potable water means water which meets the requirements of 35 Ill. Adm. Code 604 for drinking, culinary, and domestic purposes.
Drainage system means one or more artificial ditches, tile drains or similar devices which collect surface runoff or groundwater and convey it to a point of discharge.
Water surface elevation means the height, in relation to the National Geodetic Vertical Datum (NGVD) of 1929, the North American Vertical Datum (NAVD) of 1988, or other datum, where specified, of floods of various magnitudes and frequencies in the floodplains of riverine areas.
Basement means any area of the building having its floor subgrade (below ground level) on all sides.
Bathroom means any room containing a built-in flush-type toilet.
Backflow means the backflow of water or other liquids, mixtures, or substances into the distribution pipes of a potable water system from any source other than the intended source of the potable water supply.
Compaction means the increase in soil bulk density.
Stormwater means water resulting from precipitation (including rain and snow) that runs off the land’s surface, is transmitted to the subsurface, or is captured by separate storm sewers or other sewage or drainage facilities, or conveyed by snow removal equipment.
Navigable waters ’ means the waters of the United States, including the territorial sea;
Stormwater runoff means water flow on the surface of the ground or in storm sewers, resulting from precipitation.
Water Surface Elevation (WSE means the height, in relation to NAVD 1988, of floods of various magnitudes and frequencies in the floodplains of riverine areas.