14-2-1: DEFINITIONS OF TERMS:
Within the context of this title, the following words and terms shall have the meanings set forth in this section except where otherwise specifically indicated. Words and terms not defined shall have the meanings indicated by common dictionary definition.
ADMINISTRATIVE VIOLATION: An administrative violation of this title occurs when rules and procedures regarding permit applications and stormwater management permits are not followed.
ADMINISTRATOR: The person designated by the City of Watseka to administer and enforce this title, which is the City of Watseka Public Works Director.
AGRICULTURAL SUBSURFACE DRAINAGE: A water management technique driven by economic and safety concerns, where the rate at which surplus groundwater should be removed is determined primarily by the moisture/air requirements of the vegetation (commonly called “tiles”, “field tiles”, etc.).
APPLICABLE ENGINEERING PRACTICE: Procedures, methods, or materials recommended in standard engineering textbooks or references as suitable for the intended purpose.
APPLICANT: Any person, firm or governmental agency who executes the necessary forms to procure official approval of a development or permit to carry out construction of a development from the City.
APPROPRIATE USE: Only uses of the designated floodway that are permissible and will be considered for permit issuance. The list of permissible uses is contained in chapter 8 of this title.
ARMORING: A form of channel modification which involves the placement of materials (concrete, riprap, bulkheads, etc.) within a stream channel or along a shoreline to protect property above streams, lakes and ponds from erosion and wave damage caused by wave action and stream flow.
BASE FLOOD: The flood having a one percent (1%) probability of being equaled or exceeded in a given year.
BASE FLOOD ELEVATION (BFE): The highest water surface elevation that can be expected during the base flood.
BEST MANAGEMENT PRACTICES (BMP): A measure used to control the adverse stormwater-related effects of development. BMPs include structural devices (e.g., swales, filter strips, infiltration trenches, and detention basins) designed to remove pollutants, reduce runoff rates and volumes, and protect aquatic habitats. BMPs also include nonstructural approaches, such as public education efforts to prevent the dumping of household chemicals into storm drains.
BOUNCE: The difference between the normal water level and the design high water level in a wet bottom pond, and the invert of the outlet control and the design high water level for a dry bottom pond.
BUFFER: An area of predominantly vegetated land located adjacent to channels, wetlands, lakes or ponds for the purpose of reducing contaminants in stormwater that flows to such areas.
BUILDING: A structure that is principally aboveground and is enclosed by walls and a roof. The term includes a gas or liquid storage tank, a manufactured home, a mobile home or a prefabricated building. This term also includes recreational vehicles and travel trailers to be installed on a site for more than one hundred eighty (180) days, unless fully licensed and ready for highway use.
BUILDING PERMIT: A permit issued by the City for the construction, erection or alteration of a structure or building.
BULKHEAD: A retaining wall that protects property along water.
BULLETIN 70: “Frequency Distributions and Hydroclimatic Characteristics of Heavy Rainstorms in Illinois” by Floyd Huff and James Angel of the Illinois State Water Survey (1989).
BYPASS FLOWS: Stormwater runoff or groundwater from upstream properties tributary to a property’s drainage system but not under its control.
COE: The United States Army Corps of Engineers.
CHANNEL: Any river, stream, creek, brook, branch, natural or artificial depression, ponded area, flowage, slough, ditch, conduit, culvert, gully, ravine, wash, or natural or manmade drainageway, which has a definite bed and bank or shoreline, in or into which surface water, groundwater, effluent, or industrial discharges flow either perennially or intermittently.
CHANNEL MODIFICATION: Alteration of a channel by changing the physical dimensions or materials of its bed or banks. CHANNEL MODIFICATION includes damming, riprapping (or other armoring), widening, deepening, straightening, relocating, lining, and significant removal of bottom or woody rooted vegetation, but does not include the clearing of debris or removal of trash or dredging to previously documented thalweg elevations and side slopes.
CHANNELIZATION: 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).
CITY: The City of Watseka, Iroquois County, Illinois.
CLEARING: Any activity which removes vegetative ground cover.
COMMERCIAL: Sale of goods to the public at large where the traffic generated warrants construction of site improvements.
COMMERCIAL REDEVELOPMENT: Development on a parcel upon which the existing condition is buildings, parking lots and infrastructure associated with commercial activities. Additions to existing buildings and new impervious surfaces added after the effective date hereof are specifically excluded from this definition.
COMMUNITY: The City of Watseka.
COMPENSATORY STORAGE: An excavated, hydrologically and hydraulically equivalent volume of storage created to offset the loss of existing flood storage.
CONDITIONAL LETTER OF MAP AMENDMENT (CLOMA): A FEMA comment letter conditionally removing a development proposed to be located in, and affecting only that portion of the area of, a floodplain outside the regulatory floodway and having no impact on the existing regulatory floodway or base flood elevations.
CONDITIONAL LETTER OF MAP REVISION (CLOMR): A letter that indicates that FEMA will revise base flood elevations, flood insurance rate zones, flood boundaries, or floodways as shown on an effective FIRM or FBFM after the record drawings are submitted and approved.
CONSERVATION PLANNING: The practices and procedures associated with the management of soil, water, plants, plant nutrients and other elements of agricultural production. Documentation of the management system shall only be as required by the NRCS or in cases of a complaint, as requested by the Administrator in response to a notification of a complaint.
CONTROL STRUCTURE: A structure designed to limit the rate of flow that passes through the structure to a specific rate, given a specific upstream and downstream water surface elevation.
COUNTY: Iroquois County, Illinois.
CRITICAL DURATION: The duration of a storm event that results in the greatest peak runoff.
CULVERT: A structure designed to carry drainage water or small streams below barriers such as roads, driveways, or railway embankments.
DAM: Any obstruction, wall embankment, or barrier, together with any abutments and appurtenant works, constructed to store or divert water or to create a pool (not including underground water storage tanks).
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 stormwater or floodplain storage.
DEPRESSIONAL STORAGE: The volume contained below a closed contour on a one foot (1') contour interval topographic map, the upper elevation of which is determined by the invert of a surface gravity outlet.
DETENTION BASIN (SITE RUNOFF STORAGE FACILITY): A constructed structure for the temporary storage of stormwater runoff with a controlled release rate.
DEVELOPER: A person who creates or causes a development.
DEVELOPMENT: Any constructed change to real estate including: a) construction, reconstruction, repair, or replacement of a building or an addition to a building; b) 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 (180) days. If the travel trailer or recreational vehicle is on-site for less than one hundred eighty (180) days, it must be fully licensed and ready for highway use; c) drilling and mining, installing utilities, construction of roads, bridges or similar projects; d) construction or erection of levees, walls, fences, dams, or culverts, channel modifications, filling, dredging, grading, excavating, paving, or other nonagricultural alterations of the ground surface, storage materials, or deposit of solids or liquid waste; e) any other activity of man that might change the direction, height, or velocity of floodwater or surface water, including extensive vegetation removal; f) plowing and cultivation and other similar agricultural practices that do not involve filling, grading or construction of levees as regulated in subsection 14-6-5E of this title. The following are not considered development: maintenance of existing buildings and facilities such as reroofing or resurfacing of roads with an impervious surface when there is no increase in elevation.
DRAINAGE AREA: The land area upstream of a given point that may contribute runoff flow at that point from rainfall.
EFFECTIVE DATE: The effective date of this title.
ELEVATION CERTIFICATES: A form published by FEMA, or its equivalent, that is used to certify the base flood elevation and the lowest elevation of usable space to which a building has been constructed.
EMERGENCY OVERLAND FLOW ROUTE: The flow path of stormwater runoff calculated, assuming all enclosed storm sewers are inoperable.
EPHEMERAL STREAM: A stream whose bed elevation does not intersect the groundwater table. It carries flow only during and immediately after a runoff-producing rainfall event.
EROSION: The process whereby soil is detached by the action of water or wind.
EXCAVATION: Any act by which organic matter, earth, sand, gravel, rock or any other similar material is cut into, dug, quarried, uncovered, removed, displaced, relocated or bulldozed and shall include the conditions resulting therefrom.
EXISTING GRADE: The vertical location of the existing ground surface prior to excavation or filling.
EXISTING MANUFACTURED HOME PARK OR SUBDIVISION: 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: 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).
EXTENDED DETENTION: A volume of runoff temporarily detained and released over a long period of time as specified in subsection 14-6-4E of this title.
FEDERAL EMERGENCY MANAGEMENT AGENCY (FEMA): The Federal Agency and its regulations at 44 CFR 59-79, effective as of September 29, 1989, or as amended.
FEE-IN-LIEU OF DETENTION: A fee paid by a developer to the City of Watseka, commensurate with the costs and fee schedules adopted by the City based on the detention volume required for the development to meet release rates in this title. Rules and procedures for fee-in-lieu of detention are contained in chapter 11 of this title.
FILL: Any act by which earth, sand, gravel, rock or any other material is deposited, placed, replaced, pushed, dumped, pulled, transported or moved by man to a new location and shall include the conditions resulting therefrom.
FILTERED VIEW: The maintenance or establishment of woody vegetation of sufficient density to screen developments from a stream or wetland, to provide for stream bank 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.
FINAL GRADE: The vertical location of the ground or pavement surface after the grading work is completed in accordance with the site development plan.
FLOOD: A general and temporary condition of partial or complete inundation of normally dry land areas from overflow of inland waves or the unusual and rapid accumulation of runoff of surface waters from any source.
FLOOD BOUNDARY AND FLOODWAY MAP (FBFM): A floodplain management map issued by FEMA that depicts, based on detailed analyses, the boundaries of the base flood, the two-tenths percent (0.2%) probability flood, and the floodway.
FLOOD FREQUENCY: Normally expressed as a period of years, based on a percent chance of occurrence in any given year from statistical analysis, during which a flood of a stated magnitude may be expected to be equaled or exceeded. For example, the 2-year flood frequency has a fifty percent (50%) chance of occurrence in any given year. Similarly, the 100-year flood frequency has a one percent (1%) chance of occurrence in any given year.
FLOOD FRINGE: That portion of the floodplain outside of the designated floodway.
FLOOD HAZARD BOUNDARY MAP (FHBM): A map issued by FEMA that is an official Community map which depicts generalized areas of floodplains replaced by a detailed flood insurance study.
FLOOD INSURANCE RATE MAP (FIRM): A map issued by FEMA that is an official community map upon which map FEMA has delineated both the special flood hazard areas and the risk premium zones applicable to the Community. This map may or may not depict floodways.
FLOOD INSURANCE STUDY (FIS): A study of flood discharges and flood profiles for the Community, adopted and published by FEMA.
FLOOD PROTECTION ELEVATION (FPE): The elevation of the BFE plus one foot (1') of freeboard for structures within the plane limits of the base flood elevation. Outside the plane limits, the water table or 100-year design water surface elevation of any adjacent stormwater facility, including emergency overland flow routes, whichever is higher, plus one foot (1') of freeboard.
FLOODPLAIN: That land typically adjacent to a body of water with ground surface elevations at or below the base flood or the 100-year frequency flood elevation including detached special flood hazard areas, ponding areas, etc. The FLOODPLAIN is also known as the “special flood hazard areas (SFHA)”.
FLOODPROOF: Any combination of structural and nonstructural additions, changes or adjustments to structures or property which reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures and their contents.
FLOODPROOFING CERTIFICATE: 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 FPE.
FLOODWAY CONVEYANCE: The measure of the flow-carrying capacity of the floodway section and is defined using Manning’s equation as, K = 1.4863 AR2/3n where “n” is Manning’s roughness factor, “A” is the effective area of the cross-section and “R” is the ratio of the wetted area to the wetted perimeter.
FLOODWAY OR DESIGNATED FLOODWAY: Includes the channel, on-stream lakes, and that portion of the floodplain adjacent to a stream or channel which is needed to store and convey the critical duration 100-year frequency flood discharge with no more than a 0.1 foot increase in flood stage due to the loss of flood conveyance or storage, and no more than a ten percent (10%) increase in velocities.
FREEBOARD: An increment of height added to the BFE or 100-year design water surface elevation to provide a factor of safety for uncertainties in calculations, unknown local conditions, wave actions and unpredictable effects such as those caused by ice or debris jams.
FUNCTIONAL: Refers to stormwater facilities which serve their primary purpose of meeting developed release rate requirements but do not meet all of the final design conditions. For example, a detention basin, which has been excavated but has not had the side slopes graded nor the final landscaping placed, may be considered FUNCTIONAL as a site runoff storage facility.
GOOD HUSBANDRY: Generally accepted agricultural practices found in good farm management.
GRADING: Excavation or fill or any combination thereof and shall include the conditions resulting from any excavation or fill.
GROUNDWATER: Water that is located within soil or rock below the surface of the earth. Also known as “subsurface water”.
GROUNDWATER CONTROL SYSTEM: A designed system which may consist of tiles, underdrains, French drains, or other appropriate stormwater facilities the purpose of which is to lower the groundwater table to a predictable elevation throughout the year.
HISTORIC STRUCTURE: Any structure that is: a) 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; b) certified or preliminarily determined by the Secretary of the Interior as contributing to the historic district or a district preliminary determined by the Secretary to qualify as a registered historic district; c) individually listed on the State Inventory of Historic Places by the Illinois Historic Preservation Agency; d) individually listed on a local inventory of historic places that has been certified by the Illinois Historic Preservation Agency.
HYDRAULIC CHARACTERISTICS: The features of a watercourse that 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 the watercourse; gradient of the watercourse; amount and type of vegetation within the watercourse; and size, configuration, and other characteristics of structures within the watercourse. In low-lying areas, the characteristics of the overbank area also determine water conveyance capacity.
HYDRAULICALLY CONNECTED IMPERVIOUS AREA: Shall consist of those areas of concrete, asphalt and gravel surfaces, along with rooftops, which convey flows directly to an improved drainage system consisting of storm sewers or paved channels. Rooftops whose downspouts discharge to unpaved surfaces which are designed for the absorption and filtration of stormwater runoff shall not be considered as hydraulically connected impervious surfaces. Roadways whose primary conveyance is through open ditches and swales shall not be considered as hydraulically connected impervious surface. Roadways drained by curb and gutter and storm sewer, and driveways hydraulically connected to those roadways, shall be considered as directly connected impervious surface.
HYDROLOGICALLY DISTURBED: An area where the land surface has been cleared, grubbed, compacted, or otherwise modified that changes runoff, volumes, rates, or direction.
HYDRAULICALLY EQUIVALENT COMPENSATORY STORAGE: Compensatory storage either adjacent to the floodplain fill or not located adjacent to the development but can be shown by hydrologic and hydraulic analysis to be equivalent to compensatory storage located adjacent to the development.
HYDRAULICS: The science and study of the mechanical behavior of water in physical systems and processes.
HYDROLOGY: The science of the behavior of water, including its dynamics, composition, and distribution in the atmosphere, on the surface of the earth and underground.
IDNR/OWR: The Illinois Department of Natural Resources, Office of Water Resources.
IMPERVIOUS: Surfaces that cause the majority of rainfall to be converted to direct runoff. Asphalt, concrete and roofing systems are to be considered IMPERVIOUS.
INDUSTRIAL REDEVELOPMENT: Development on a parcel upon which the existing condition is buildings, parking lots and infrastructure associated with industrial activities. Additions to existing buildings and new impervious surfaces added after the effective date hereof are specifically excluded from consideration as INDUSTRIAL REDEVELOPMENT.
INTERMITTENT STREAM: A stream whose bed intersects the groundwater table for only a portion of the year on the average, or any stream which flows continuously for at least one month out of the year but not the entire year.
LAKE: A natural or artificial body of water encompassing an area of two (2) or more acres, which retains water throughout the year.
LETTER OF MAP AMENDMENT (LOMA): The official determination by FEMA that a specific structure is not in a regulatory floodplain. A "LOMA" amends the effective FHBM, FBFM, or FIRM.
LETTER OF MAP REVISION (LOMR): A letter from FEMA that revises base flood elevations, flood insurance rate zones, flood boundaries, or floodway as shown on an effective FHBM, FBFM, or FIRM.
LOT: An area of land, with defined boundaries, that is designated in the Official Assessor’s records as being one parcel.
MAJOR STORMWATER SYSTEM: That portion of a stormwater facility needed to store and convey flows beyond the capacity of the minor stormwater system.
MANUFACTURED HOME: 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 (180) consecutive days. The term MANUFACTURED HOME does not include a recreational vehicle.
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.
MASS GRADING: Development in which the primary activity is a change in topography affected by the movement of earth materials.
MINOR STORMWATER SYSTEM: Shall consist of all infrastructure including curb, gutter, culverts, roadside ditches and swales, storm sewers, and sub-surface drainage systems intended to convey stormwater runoff at less than a 100-year flood frequency. The design frequency for minor stormwater systems shall be in accordance with the applicable ordinances of the Community or Highway Department jurisdiction.
MITIGATION: Measures taken to offset negative impacts from development in wetlands or the floodplain.
NRCS: The United States Department of Agriculture, Natural Resources Conservation Service.
NATIONAL FLOOD INSURANCE PROGRAM (NFIP): A Federal program whose requirements are codified in title 44 of the Code of Federal Regulations.
NATURAL: In reference to watercourses, means 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.
NATURAL DRAINAGE: Channels formed in the existing surface topography of the earth prior to changes caused by unnatural causes.
NET BENEFIT IN WATER QUALITY: The institution of best management practices as part of a development that, when compared to the pre-development condition, can be judged to reduce downstream sediment loading or pollutant loadings.
NET WATERSHED BENEFIT: A finding that, when compared to the existing condition, the developed project will do one of the following: substantially reduce (more than 10 percent) downstream peak discharges; reduce downstream flood stages (more than 0.1 foot); or reduce downstream damages to structures occurring in the pre-development condition. The demonstration of one of these conditions must be through detailed hydrologic and hydraulic analysis of watersheds on a regional scale as approved by the Administrator.
NEW MANUFACTURED HOME PARK OR SUBDIVISION: 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 on or after April 1, 1990.
NONRIVERINE: Areas not associated with a stream or river such as isolated depressional storage areas, ponds and lakes.
OBSERVATION STRUCTURES: Structures built on a field tile where the pipe inflow and outflow is visible upon removal of a lid.
OPEN CHANNEL: A conveyance system with a definable bed and banks carrying the discharge from field tiles and surface drainage. Open channels do not include grassed swales within farm fields under agricultural production, which are ephemeral in nature.
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 characteristic.
OVERLAND FLOW PATH: A design feature of the major stormwater system which carries flows in excess of the minor stormwater system design capacity in an open channel or swale, or as sheet flow or weir flow over a feature designed to withstand the particular erosive forces involved.
PARCEL: All contiguous land under common ownership or control including right(s)-of-way to be dedicated in conjunction with the proposed development.
PERENNIAL STREAMS: Riverine watercourses whose thalweg generally intersects the groundwater table elevation and flows throughout the year.
PERMITTING AUTHORITY: The City of Watseka.
POND: Any inland water body fed by spring or surface water flow that is not a lake.
PRIMARY GRAVITY OUTLET: The outlet structure designed to meet the release rate requirements of this title.
PROFESSIONAL ENGINEER: An engineer registered in the State of Illinois, under the Illinois Professional Engineering Practice Act (225 ILCS 325/1 et seq.), as amended.
PROFESSIONAL LAND SURVEYOR: A land surveyor registered in the State of Illinois under the Illinois Land Surveyors Act (225 ILCS 330/1 et seq.), as amended.
PROPERTY: Contiguous land under single ownership or control.
PUBLIC BODIES OF WATER: 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 conditions, 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: A flood control project, which will be operated and maintained by a public agency to reduce flood damages to existing buildings and structures, which includes 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.
PUBLIC FLOOD EASEMENT: An easement acceptable to the appropriate jurisdictional body that meets the regulations of the IDNR/OWR, and the Community, and that provides legal assurances that all areas subject to flooding in the created backwater of the development will remain open to allow flooding.
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.
RECORD DRAWINGS: Drawings prepared, signed, and sealed by a registered professional engineer or registered land surveyor representing the final as-built record of the actual in-place elevations, location of structures, and topography.
RECREATIONAL VEHICLE OR TRAVEL TRAILER: A vehicle which is: a) built on a singe chassis; b) four hundred (400) square feet or less when measured at the largest horizontal projection; c) designed to be self-propelled or permanently towable by a light duty truck; and d) designed primarily not for use as a permanent dwelling, but as a temporary living quarters for recreational camping travel or seasonal use.
REGISTERED STRUCTURAL ENGINEER: A person licensed under the laws of the State of Illinois as a structural engineer.
REGULATORY FLOODPLAIN: The floodplain as depicted on maps recognized by FEMA as defining the limits of the SFHA.
REGULATORY FLOODWAY: Those portions of the floodplain depicted on maps as a floodway and recognized by the IDNR/OWR for regulatory purposes.
REMOVAL: Cutting vegetation to the ground or stumps, complete extraction, or killing by spraying.
RETENTION FACILITY. A facility that stores stormwater runoff without a gravity release.
RIVERINE: Related to, formed by, or resembling a channel (including creeks and rivers).
RUNOFF: The waters derived from melting snow or rain falling within a tributary drainage basin that exceeds the infiltration capacity of the soils of that basin.
(SFHA) SPECIAL FLOOD HAZARD AREA: An area having special flood, mudslide or mudflow, or flood-related erosion hazards, and which area is shown on an FHBM or FIRM as Zone A, AO, A1-30, AE, A99, AH, VO, V1-30, VE, V, M, or E.
SEASONAL HIGH GROUNDWATER TABLE: The upper limits of the soil temporarily saturated with water, being usually associated with spring wetness conditions. This may be indicated by soil mottles with a Munsell color of two (2) chroma or less.
SEDIMENT TRAP: A structure or area that allows for the temporary deposit and removal or disposal of sediment materials from stormwater runoff.
SEDIMENTATION: The process that deposits hydraulically moved soils, debris, and other materials either on other ground surfaces or in bodies of water or stormwater drainage systems.
SEEPAGE: The movement of drainable water through soil and rock.
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.
SITE: A parcel on which development is proposed or has occurred. The area of the site shall include rights-of-way to be dedicated in conjunction with the development.
SITE DEVELOPMENT PERMIT: A permit issued by the City which permits development, or limited development, of a site in accordance with approved plans and in accordance with this title.
STORMWATER FACILITY: All ditches, channels, conduits, bridges, culverts, levees, ponds, natural and manmade impoundments, wetlands, riparian environment, tile, swales, sewers, or other natural or artificial structures or measures which serve as a means of draining surface and subsurface water from land.
STORMWATER MANAGEMENT PERMIT: The permit issued under chapter 4 of this title.
STRUCTURE: The results of a built change to the land constructed on or below the ground, including the construction, reconstruction or placement of a building or any addition to a building; installing 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 unless they are fully licensed and ready for highway use.
SUBSTANTIAL IMPROVEMENT: If any one of the following three (3) conditions applies when work is performed on an existing building, then the work will be classified as a SUBSTANTIAL IMPROVEMENT:
   A.   An improvement made to a building whose cost is equal to or exceeds fifty percent (50%) of the building's market value before the improvement;
   B.   Reconstruction or repair of a building, the cost of which equals or exceeds fifty percent (50%) of the market value of the building before reconstruction or repair; or
   C.   Additions to an existing building, the cost of which equals or exceeds fifty percent (50%) of the market value of a structure, or increases the floor area by more than twenty percent (20%).
Note, that if a building is substantially improved, then the entire building must comply with the building protection standards.
SUBSURFACE DRAINAGE: The removal of excess soil water to control water table levels at predetermined elevations for structural, environmental or other reasons in areas already developed or being developed for agricultural, residential, industrial, commercial, or recreational uses.
SUBSURFACE WATER: Water beneath the ground or pavement surface. Sometimes referred to as “groundwater” or "soil water”.
T FACTOR: The soil loss tolerance. It is the maximum amount of erosion at which the quality of a soil as a medium for plant growth can be maintained. Erosion losses are estimated by Universal Soil Loss Equation (USLE) and Revised Universal Soil Loss Equation (RUSLE).
THALWEG: A line along the lowest point in a channel.
TRANSITION SECTION: Reaches of the stream or floodway where water flows from a narrow cross- section to a wide cross-section, or vice versa.
USABLE SPACE: Space used for dwelling, storage, utilities, or other beneficial purposes including, without limitation, basements.
VEGETATION: All plant growth, especially trees, shrubs, mosses, and grasses.
WATER TABLE: The upper limit of a free water surface in a saturated soil or underlying material.
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 manmade drainageway, which has a definite channel, bed and banks, in or into which stormwater runoff and floodwater flow either regularly or intermittently.
WATERS OF THE U.S.: As defined by the United States Army Corps of Engineers in their Federal Methodology for the Regulation of Wetlands. For purposes of this title, “waters of the U.S.” include wetlands, lakes, rivers, streams, creeks, bogs, fens, and ponds. "Waters of the U.S." do not include maintained stormwater facilities.
WATERSHED: All land area drained by, or contributing water to, the same stream, lake, stormwater facility, or draining to a point.
WATERSHED BENEFIT: See definition of Net Watershed Benefit.
WATERSHED CHARACTERISTICS: Include land use, physiology, habitat, climate, drainage system and community profile.
WATERSHED PLAN: A study and evaluation of an individual drainage basin's stormwater management, floodplain management, water quality and flood control needs and capabilities.
WETLAND: An area of land which meets the criteria as defined in current Federal methodology recognized by the U.S. Army Corps of Engineers, whether or not the area of land is subject to the regulatory authority of U.S. Army Corps of Engineers, or any other regulatory authority.
(Ord. 2421, 6-24-2014, eff. 6-24-2014)