For the purposes of this chapter, certain terms are defined
and set forth below:
Any negative impact on plant, soil, air or water resources
affecting their beneficial uses, including recreation, aesthetics,
aquatic habitat, quality, and quantity.
Any person, firm, or governmental agency who or which executes
the necessary forms to procure official approval of a development
or permit to carry out construction of a new development or redevelopment
from the Village.
The elevation at all locations delineating the level of flooding
resulting from the one-hundred-year-frequency flood event, which has
a 1% chance of occurring in any given year.
A permit issued by the Village for the construction, erection
or alteration of a structure or building and the related ground and
surface preparation prior to and after completion of construction,
erection or alteration of a structure or building.
Stormwater runoff from upstream properties tributary to a
property's drainage system but not under its control.
Formally attesting that the specific inspections and tests
were performed, and that such inspections and tests comply with the
applicable requirements of this chapter.
Any defined river, stream, creek, brook, branch, natural
or artificial depression, ponded area, on-stream lake or impoundment,
karst area (sinkhole), flowage, slough, ditch, conduit, culvert, gully,
ravine, wash, or natural or man-made drainageway, which has a definite
bed and bank or shoreline, in or into which surface water or groundwater
flows, either perennially or intermittently.
Alteration of a channel by changing the physical dimensions
or materials of its bed or banks. Channel modification includes damming,
riprapping (or other armoring), filling, widening, deepening, straightening,
relocating, lining, and significant removal of bottom or woody rooted
vegetation. Channel modification does not include the man-made clearing
of debris or removal of trash.
Any activity which removes the natural vegetative ground
cover.
An artificially excavated, hydraulically equivalent volume
of storage within the floodplain used to balance the loss of natural
flood storage capacity when fill or structures are placed within the
floodplain.
Any channel, pipe, sewer or culvert used for the conveyance
or movement of water, whether open or closed.
A one yard by one yard by one yard amount of material in
excavation and/or fill.
A facility constructed or modified to provide for the temporary
storage of stormwater runoff and the controlled release by gravity
of this runoff at a prescribed rate during and after a flood or storm.
The amount of time stormwater is held within a detention
basin.
Any man-made change to real estate or property, including:
The division or subdivision of any duly recorded parcel of property;
Construction, reconstruction or placement of a building or any
addition to a building;
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 180 days per year;
Construction of roads, bridges, or similar projects;
Redevelopment of a site;
Filling, dredging, grading, clearing, excavating, paving or
other nonagricultural alterations of a ground surface;
Storage of materials or deposit of solid or liquid waste;
Any other activity that might alter the magnitude, frequency,
direction, or velocity of stormwater flows from a property.
A plan, including engineering drawings and supporting calculations,
which describes the existing stormwater drainage system and environmental
features, including grading, as well as proposed alterations or changes
to the drainage system and environment of a property.
A detention basin designed to drain after temporary storage
of stormwater flows and to normally be dry over much of its bottom
area.
The general process whereby soil or earth is moved by rainfall,
flowing water, wind or wave action.
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 from such actions.
The volume and rate of flow of stormwater discharged from
a new development or redevelopment which is or will be in excess of
that volume and rate which existed before development or redevelopment.
The vertical location of the existing ground surface prior
to excavation or filling.
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.
The vertical location of the ground surface after grading
work is completed in accordance with the engineering plans.
That area as designated by the Federal Emergency Management
Agency (FEMA) on either side of the floodway. This area is subject
to inundation from the base flood but conveys little or no flow.
A very generalized map prepared by the Federal Emergency
Management Agency (FEMA) which shows only where floodplains are located
based on very basic data. FHBMs do not include base flood elevations.
A map prepared by the Federal Emergency Management Agency
(FEMA) that depicts the special flood hazard area (SFHA) within a
community. This map includes insurance rate zones and regulatory floodplains
and may or may not depict regulatory floodways.
That land adjacent to a body of water with ground surface
elevations at or below the base flood or the one-hundred-year frequency
flood elevation which is subject to inundation. The floodplain as
designated by the Federal Emergency Management Agency (FEMA) is also
known as the "special flood hazard area (SFHA)." These areas can be
found on the (FIRM), Flood Boundary and Floodway Map, or the Flood
Hazard Boundary Map (FHBM) of the community. This area is the collective
combination of the regulatory floodway and the flood fringe.
The channel and that portion of the floodplain, including
on-stream lakes, adjacent to a stream or watercourse which is needed
to store and convey the anticipated existing and future one-hundred-year-frequency
flood discharge with no more than a 0.1-foot increase in stage due
to any loss of flood conveyance or storage and no more than a 10%
increase in velocities. Floodways are designated by FEMA on some Flood
Insurance Rate Maps and Flood Boundary and Floodway Maps. However,
there are floodways on all streams, whether mapped by FEMA or not.
Excavation or fill or any combination thereof, and shall
include the conditions resulting from any excavation or fill.
A graph showing, for a given location on a stream or conduit,
the flow rate with respect to time.
This method estimates runoff volume and runoff hydrographs
for the point of interest by generating hydrographs for individual
subareas, combining them, and routing them through stream lengths
and reservoir structures. Factors such as rainfall amount and distribution,
runoff curve number, time of concentration, and travel time are included.
That area of property that is covered by materials other
than soil and vegetation and that has no intended capacity to absorb
water, such as parking lots, driveways, sidewalks, patios, tennis
courts, roofs and other structures.
The passage or movement of water into the soil surfaces.
A sediment, commonly nonstratified and unconsolidated, composed
predominately of silt-sized particles with accessory clay and sand.
An individual platted parcel in an approved subdivision.
That portion of a drainage system needed to store and convey
flows beyond the capacity of the minor drainage system.
That portion of a drainage system designed for the convenience
of the public. It consists of street gutters, storm sewers, small
open channels, and swales and, where man-made, is to be designed to
handle the two-year runoff event.
Mitigation is when the prescribed controls are not sufficient
and additional measures are required to offset the development, including
those measures necessary to minimize the negative effects which stormwater
drainage and development activities might have on the public health,
safety and welfare. Examples of mitigation include, but are not limited
to, compensatory storage, soil erosion and sedimentation control,
and channel restoration.
As described in the Illinois Department of Transportation
"Drainage Manual," is based on the principle that the maximum rate
of runoff from a given drainage area occurs at that point in time
when all parts of the watershed are contributing to the flow. The
rainfall generating the peak flow is assumed to be of uniform intensity
for the entire watershed with a rainfall duration equal to the time
of concentration.
Conditions resulting from physical, chemical, and biological
processes without intervention by man.
Channels formed in the existing surface topography of the
earth prior to changes made by unnatural causes.
A rainfall, runoff, or flood event having a 1% chance of
occurring in any given year. A twenty-four-hour storm duration is
assumed unless otherwise noted.
All contiguous land in one ownership.
The maximum rate of flow of water at a given point in a channel
or conduit.
Any person to whom a building permit is issued.
Any individual, firm or corporation, public or private, the
State of Illinois and its agencies or political subdivisions, the
United States of America, and its agencies or political subdivisions,
and any agent, servant, officer or employee of any of the foregoing.
Provision for overland paths for all areas of a property,
including depressional areas that may also be drained by storm sewer.
Land that is best suited to food, feed, or forage fiber and
oilseed crops. It may be cropland, pasture, woodland, or other land,
but it is not urban and built-up land or water areas. It is either
used for food or fiber or is available for those uses. The soil qualities,
growing season and moisture supply are those needed for a well-managed
soil to economically produce a sustained high yield of crops. Prime
farmland produces the highest yields with minimum inputs of energy
and economic resources, and farming it results in the least damage
to the environment.
A parcel of real estate.
A facility designed to completely retain a specified amount
of stormwater runoff without release except by means of evaporation,
infiltration, emergency bypass or pumping.
The process that deposits soils, debris, and other materials
either on other ground surfaces or in bodies of water or stormwater
drainage systems.
A land surface depression or blind valley which may or may
not have surface openings to cavernous underground areas and are the
result of water movement through silts and jointed limestone. These
conditions make such areas unstable and susceptible to subsidence
and surface collapse. Fractures in the limestone may channel runoff
water to public or private water supplies, making those sources especially
susceptible to groundwater contamination.
A parcel of land, or a contiguous combination thereof, where
grading work is performed as a single unified operation.
The line which delineates relatively level building areas
from areas where slopes exceed 8% and where special precautions must
be taken.
A closed conduit for conveying collected stormwater.
All means, natural and man-made, used for conducting stormwater
to, through or from a drainage area to the point of final outlet from
a property. The stormwater drainage system includes but is not limited
to any of the following: conduits and appurtenance features, canals,
channels, ditches, streams, culverts, streets, storm sewers, detention
basins, swales and pumping stations.
The waters derived from melting snow or rain falling within
a tributary drainage basin which are in excess of the infiltration
capacity of the soils of that basin, which flow over the surface of
the ground or are collected in channels or conduits.
Any river, creek, brook, branch, flowage, ravine, or natural
or man-made drainageway which has a definite bed and banks or shoreline,
in or into which surface water or groundwater flows, either perennially
or intermittently.
Any activity which removes the vegetative surface cover,
including tree removal, by spraying or clearing, and storage or removal
of topsoil.
A runoff, rainfall, or flood event having a 10% chance of
occurring in any given year. A twenty-four-hour storm duration is
assumed unless otherwise noted.
The elapsed time for stormwater to flow from the most hydraulically
remote point in a drainage basin to a particular point of interest
in that watershed.
All of the land surface area that contributes runoff to a
given point.
A runoff, rainfall, or flood event having a 50% chance of
occurring in any given year. A twenty-four-hour storm duration is
assumed unless otherwise noted.
Land on which there are no structures or only structures
which are secondary to the use or maintenance of the land itself.
All land area drained by, or contributing water to, the same
stream, creek, ditch, lake, marsh, stormwater facility, groundwater
or depressional area.
A detention basin designed to maintain a permanent pool of
water after the temporary storage of stormwater runoff.
Wetlands are defined by regulation as "those areas that are
inundated or saturated by surface or groundwater at a frequency and
duration sufficient to support, and under normal circumstances do
support, a prevalence of vegetation typically adapted for life in
saturated soil conditions." For general, but not inclusive, locations
of designated wetlands, refer to mapping prepared jointly by the U.S.
Department of Interior, Fish and Wildlife Service and the Illinois
Department of Natural Resources, Office of Resource Conservation;
National Wetlands Inventory Mapping, 1987. The applicant may be required
to provide a field investigation by a qualified wetland delineator.
