Engineering Division 

Engineering Definitions

Standard Definitions used in engineering practices are provided below. You may also visit our links page for links to various agencies contained below.

Aggregate

Dry, granular construction materials such as sand, crushed stone, and gravel.

ANSI

American National Standards Institute, Inc.

Approved

Unless otherwise stated, materials, equipment or methods accepted and approved by the Village Engineering Division and/or Public Works Department.

Approved Equal

A manufactured product, or a method or procedure, having the same characteristics and similar in degree or other standard of comparison to that specified.

Area of Special Flood Hazard

The land which is subject to a one percent chance of flooding annually. This area may also be identified as that which is subject to the l00-year flood. The area is designated as Zone A, Al-99, AH or AO on the maps provided by the Federal Insurance Administration.

As-Built

A drawing/survey that shows all pertinent details of a newly completed structure including (but not limited to) dimensions, setbacks, and elevations.

Assumed Benchmark

(See grading guidelines.)

Auger

Backfill

Earth used to fill a trench or excavation.

Base Flood

The flood having a one percent chance of being equaled or exceeded in any given year. The base flood is also known as the l00-year flood. If the l00-year flood information is not available, the base flood shall be the flood of record.

Base Flood Area

The land area subject to inundation by waters of the base flood.

Base Flood Elevation (BFE)

The highest water surface elevation within the floodplain for a 100 year flood event.

Basin

Space above or below ground capable of retaining or detaining water or debris.

Berm

A bench or terrace between two slopes.

Brick Ledge

A course of brick which sits on top of and within a notch in the foundation wall of a structure and allows the structure to have a higher top of foundation on the interior of the foundation wall while also maintaining the required amount of exposed foundation wall on the exterior face.

Buffalo Box (B-Box)

The small water valve located on Village property, usually in the parkway, which can be used to turn the water service on or off. Appears as a brass cap in the parkway approximately three inches (3") in diameter. All disconnections of old services and reconnections of new services must take place at the mains-NOT the B-Box.

Building Permit

A written authorization issued by the Village of Glenview for the construction, erection or alteration of a structure or building.

CCHD

Cook County Highway Department. Visit our links page for a link to CCHD.

Catch Basin

A well or reservoir into which surface water may drain off.

Compensatory Storage

An artificially excavated volume of storage within the base flood area 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.

Concentrated Flow

Flowing water that has been accumulated into a single fairly narrow stream.

Contractor

The contractor awarded the prime contract for the work by the Village, Owner or developer and/or any of their subcontractors, suppliers or fabricators. The contractor(s) must be licensed and bonded with the Village of Glenview prior to and during all phases of the work.

Conveyance

Any natural or man-made channel or pipe in which concentrated water flows. Differs from a 'dentention basin' in that water is not stored on site.

Culvert

A covered channel or large-diameter pipe that takes a watercourse below ground level.

Curb Cut

The removal by qualified contractor of the mountable curb, the 'bump' you must drive over when entering your private driveway from the street. All curb cut work must be approved by Engineering prior to the work being done. The new curb is called a 'depressed curb.'

DBH

Diameter at Breast Height

DPW

Village of Glenview-Department of Public Works. Contains Water, Sewer, and Street services.

Design Flood

The peak discharge (when appropriate, the volume, stage, or wave crest elevation) of the flood associated with the probability of exceedance selected for the design of an encroachment in a FEMA flood plain.

Design Frequency

The recurrence interval for hydrologic events used for design purposes. As an example, a design frequency of 50 years means a storm of a magnitude that would be expected to recur on the average of every 50 years.

Design Storm

That particular storm which contributes runoff which the drainage facilities were designed to handle.

Detention Basin

A reservoir without control gates for storing water over brief periods of time until the stream has capacity for ordinary flow plus released water. The basin differs from 'conveyance' methods in that the basin holds water for a period of time while the conveyance method is a means of moving water through an area towards an inlet or other drainage structure. See 'Dry Basin' and 'Wet Basin.'

Developer

The individual(s), company, corporation, or other legal entity who holds title to or an equitable interest in the property on which construction operations are to be conducted.

Development

Any man-made change to improved or unimproved real estate, including but not limited to construction of or substantial improvements to buildings or other structures, the placement of mobile homes, mining, dredging, filling, grading, paving, excavation or drilling operations.

Ditch

A trench in the earth providing for collection and conveyance of storm water-usually unlined.

Drainage Course

Any path along which water flows when acted upon by gravitational forces.

Drainage Divide

The rim of a drainage basin.

Drainage Way

A means of passing water from one place to another such as a swale, ditch, creek, stream, river, or watercourse

Dry Basin

A basin designed to hold water only in a storm event.

Easement

The right held by one person or entity over another person's land for a specific purpose; rights of tenant are excluded.

Emergency Overflow System

Those portions of the surface water control system intended to mitigate danger to human life and serious damage to buildings and other facilities in the event of a rare, major flood event.

Engineering Plan

A drawing or set of drawings sealed by a Registered Professional Engineer which illustrates and/or describes all aspects of the site development. See also Frequently Asked Questions" link.

Environmentally Significant Area

A larger area encompassing an important natural or cultural resource (Primary Area) deemed significant by the Village. This area is determined to be integrally related to the integrity and quality of a Primary Area through direct or indirect relationships (e.g. the Grove National Historic Site area, which is bounded by Milwaukee Avenue on the southwest, the Interstate 204 (tollway) on the west, Lake Avenue on the north, Glenbrook Estates and Glenview Woodland Subdivisions ono the east, and the Chicago and Northwestern Railroad on the southeast.

Erosion Control

See 'Silt Fence.'

Escrow

A fee collected for certain types of work until such time as that work can be inspected and approved by a Village Engineering Inspector.

Excavation

Any act by which organic matter, earth, sand, gravel, rock or any other similar material is cut into, dug, quarried, uncovered, removed, displaced, or relocated, including the conditions resulting therefrom.

Excess Stormwater

That portion of stormwater runoff which exceeds the material drainage channels capacity to serve a specific watershed.

Exposed Foundation

(See 'Top of Foundation')

Fill

Any act by which earth, sand, gravel, rock or any other material suitable for its intended use is deposited, placed, replaced, pushed, dumped, pulled, transported or moved by man to a new location, including the conditions resulting therefrom.

Flood

The condition existing when the waters of any watercourse, pond, or depression temporarily rise to a height above their normal levels and overflow the boundaries within which they are ordinarily contained. It also includes the unusual rapid accumulation or runoff of surface waters.

Flood Frequency

A period of years, based on a statistical analysis, during which a flood of a stated magnitude may be expected to be equaled or exceeded.

Flood 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.

Flood Hazard Boundary Map

An official map of the Village, issued or approved by the Administrator of the Federal Insurance Administration, on which the areas having special flood hazards have been drawn and designated as Zone A.

Flood Insurance Study (FIS)

An examination and evaluation of hydrologic and hydraulic data sponsored by the Federal Insurance Administration to determine base flood flows, elevations, areas, and floodways. The FIS also determines flows, elevations, and areas of flood having lesser and greater frequencies of occurrence.

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 base flood elevations of the water surface of the l00-year flood along the watercourses of the Village.

Flood Protection Elevation

The elevation to which uses regulated by this ordinance are required to be elevated or floodproofed.

Flood Return Period

Same as Flood Frequency.

Floodplain

The special flood hazard lands adjoining a watercourse, whose surface elevation is lower than the base flood elevation, that are subject to periodic inundation during floods.

Floodproofing

Modifications to structures made to reduce flood damages. These changes may be made to existing structures or incorporated in the design of new structures. In all instances, floodproofing must be watertight and must be adequate without the need for human intervention.

Floodway

The channel of a watercourse and those portions of the adjoining floodplains which are required to carry and discharge the l00-year flood with no significant increase in the base flood elevation.

Floodway Encroachment Lines

The lateral boundaries of the floodway which separate it from the flood fringes.

Freeboard

An increment of elevation added to the base flood elevation to provide a factor of safety for uncertainties in calculations, unknown localized conditions, wave actions, and unpredictable effects such as may be caused by ice or debris jams.

Grading Plan

Prepared by an Illinois Professional Engineer. Includes existing and proposed topography of the SFR done in USGS (NGVD of 1929) Datum. Extend existing topographical information (minimum 50' around the proposed SFR). Topography shall be represented in one (1) foot contours and spot grades as necessary to clearly show the existing patterns of drainage and conditions of the lot. Please note that the Architectural and Individual Lot Engineering (Site/Grading) Plan shall match (i.e. if brick ledges are shown on the Engineering Plan those ledges shall be reflected on the Architectural foundation and elevation drawings). See also "Grading Guidelines & Frequently Asked Questions" section.

Grease Basin

A trap required in restaurants for grease. The trap removes the grease from the waste water before it enters the sanitary sewer system.

Hydrograph

A graph of discharge, on the vertical axis, versus time, on the horizontal axis. Shows the volume of the stream flow passing a 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 based on the difference in elevations between the surface levels of the water. Hydrostatic pressure may also be horizontal, imposing forces on walls causing them to crack or fail.

IDOT

Illinois Department of Transportation. Visit our links page for a link to IDOT.

Imperviousness

The portion of a subbasin, subwatershed, or watershed, expressed as a percentage, that is covered by surfaces such as roof tops, parking lots, sidewalks, driveways, streets, and highways. Surfaces that do not absorb rainwater and cause additional runoff.

Infiltration

Water, other than wastewater, that enters a sanitary sewer system-or sewer connections-from the ground through defective pipes, pipe joints, connections, or manholes.

Invert

The floor or bottom of a conduit.

JULIE

Joint Utility Locating Information for Excavators. JULIE must be contacted anytime excavation is done-whether on Village or private property. 1-800-892-0123

MWRD

Metropolitan Water Reclamation District of Greater Chicago. Visit our links page for a link to MWRD.

Mobile Home

A structure transportable in one or more sections, which is built on a permanent chassis and designed to be used with or without a permanent foundation when connected to the required utilities. It does not include recreational vehicles or travel trailers.

Mobile Home Park

A parcel or contiguous parcels of land which has been so designated and improved that it contains two or more mobile home lots available to the general public for sale or rent and the placement thereon of mobile homes for occupancy.

NGVD

National Geodetic Vertical Datum (1929)

NPDES II

National Pollution Discharge Elimination System Phase Two -- the Environmental Protection Agency's program to control the discharge of pollutants to waters of the United States. NPDES is part of the federal Clean Water Act, which requires point and non-point source dischargers to obtain permits.

Notice of Intent

A formal notice to the EPA or a state agency having delegated NPDES authority (Glenview has this authority) that a construction project seeking coverage under a General Permit is about to begin. The "NOI" provides information on the owner, location, and type of project, and certifies that the permittee will comply with conditions of the construction General Permit. The NOI is not a permit application and no approval is required. Some local permits may require submittal of a Notice of New Construction (NONC) in lieu of filing a NOI with the state or EPA.

One Hundred Year Flood

A flood magnitude with a one percent statistical chance of being equaled or exceeded during any year. A flood this large would be reached once during a l00-year period, on the average.

Open Channel

Any conveyance in which water flows with a free surface.

Open Cut

Cutting of the pavement surface in order to access a main for the purposes of disconnection or new connection. Allowed ONLY with approval by Engineering Division.

Outfall

The discharge or point of discharge of a culvert or other closed conduit (i.e. sump pump).

Overflow System

See "Emergency Overflow System."

Owner

The individual(s) who holds title to or an equitable interest in the property on which construction operations are to be conducted.

Parcel

All contiguous land in one ownership.

Parkway

The land between the pavement edge or curb, and the public walkway OR the property line as defined by plat of survey.

P.E.

A State of Illinois Licensed Professional Engineer.

Permeability

Surfaces that allow for the absorbtion of rainwater and runoff. The property of soils which permits the passage of any fluid.

Permittee

Any person to whom a site development permit is issued.

Plumbing Worksheets

Required for any new home or any addition to a home that involves a change in the number of plumbing fixtures. This form is available at the Permit desk of the Development Department in Village Hall. We recommend that your Architect fill out the information on both sheets and return them to the Engineering Division as soon as possible.
NOTE: Plumbing information provided on the permit application does not fulfill this requirement.

Positive Drainage

Slope away in all directions from the structure in question at a minimum of one percent (1%).

Precipitation

Discharge of atmospheric moisture such as rain, snow or hail, measured in depth of fall or in intensity of fall in unit time.

Private Right-of-Way

(See 'Right-of-Way') A right-of-way which is neither owned and maintained by the Village of Glenview or any other jurisdictional agency except a homeowner's association.

Project Site

A lot or parcel of land, or a contiguous combination thereof, where the development is to be performed.

Provide

Furnish, install and connect.

Retention Basin

A wet bottom stormwater storage area designed to be maintained as a pond or free water surface.

Right-of-Way

That portion of land set aside for a public roadway including the parkway land on either side of said roadway, public walks on either side of said roadway, and 1 (one) foot of land on far side of public walkways. This land is owned and maintained by either the Village of Glenview, the Illinois Department of Transportation, Cook County, Maine Township, or Northfield Township. (If work to be done is within a right-of-way not owned by the Village of Glenview, it shall be necessary to obtain permission from the owner of said right-of-way before commencing work. All other work in Village right-of-ways shall require a permit from the Village unless the right-of-way is private.)

Rim

An outer edge or border, sometimes raised or projecting.

Risk Premium Rate Zones

Flood hazard areas designated according to the degree of flooding they would experience during the base flood. The symbols used to designate these zones are as follows:

Zone symbol:

A -- Area of special flood hazard without water surface elevations determined.

Al-99 -- Area of special flood hazard with water surface elevations determined.

AH -- Area of special flood hazards having a level water surface (ponding) with water depths between (l) and (3) ft.

AO -- Area of special flood hazards having a sloping water surface (sheet runoff) with water depths between (l) and (3) ft.

VO -- Area of special flood hazards having shallow water depths and/or unpredictable flow paths between (l) and (3) ft. and with velocity.

B -- Area of moderate flood hazards.

C -- Area of minimal hazards.

Riverine

Relating to, formed by, or resembling a river (including tributaries), stream, creek, or brook.

Runoff

The surface waters that exceed the soil's infiltration rate and depression storage. That portion of precipitation that appears as flow in streams.

SFR

Single Family Residence

Sanitary Sewer

A sewer structure designed to move waste.

Sedimentation Basin

A surface water runoff storage facility intended to trap suspended solids, suspended and buoyant debris, and absorb potential pollutants that are carried by surface water runoff.

Silt Fence

A fabric-like material which allows water to pass through, but restricts granular material. May also be known as 'rip-rap' or 'erosion control fence.'

Site Development Plan

A drawing or other written description sealed by a Registered Architect or Licensed Professional Engineer which illustrates and/or describes all aspects of the site development. See also "Grading Guidelines & Frequently Asked Questions" section.

Slope

Inclination of the face of an embankment, expressed as the ratio of horizontal to vertical projection.

Spot Elevation

The proposed and/or 'as-built' elevation of a particular point on land as measured by a surveyor.

Spot Survey

Used to verify the elevation at the top of foundation of a newly poured structure foundation. Prepared by an Illinois licensed Surveyor, this document contains:

• lot configuration with dimensions
• as-built dimensions from structure corners to lot lines (noting whether to overhang or foundation)
• as-built elevation of top of foundation or slab
• as-built dimensions of foundation or slab
• as-built location and elevation of brick ledges
• as-built location and elevation (top and bottom) of retaining walls
• as-built location and elevation of garage floor opening
• as-built location and elevations of any other openings in the foundation

Storage Basin

Space for detention or retention of water for future flow, naturally in channel and marginal soils, or artificially in reservoirs.

Stormwater Runoff

Rainfall which is not absorbed or detained by soil or plant material, or lost by evaporation.

Storm Sewer

A sewer structure designed to move storm run-off. A conveyance system.

Structure

A walled and roofed building, including a gas or liquid storage tank, that is principally above ground, as well as a mobile home.

Substantial Improvement

Any repair, reconstruction, or improvement of a structure, the cost of which equals or exceeds fifty percent (50%) of the market value of the structure either before the improvement or repair is started, or if the structure has been damaged, and is being restored, before the damage occurred.

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 or site documented as deserving preservation by the Illinois Department of Conservation or listed on the National Register of Historic Places.

Subwatershed

Drainage area composed of two or more subbasins.

Swale

A depressed area of land completely covered with sod growth and contoured to facilitate the surface flow of water to a tributary, storage area or other disposition point.

Swamp Policy

SWAMP Program- The Stormwater Area Management Program is the established policy regarding drainage improvements in the Village of Glenview. It provides guidance for the maintenance and replacement of existing storm sewers and sets the policy for the installation of new sewers, including financial participation.

• Drainage improvements in sewered areas: Inspected, maintained, repaired and replaced by the Village at 100% Village cost.
• Drainage improvements in unsewered areas:
  • Village will maintain new culvert and swale systems if designed to Village standards
  • Village will pay 100% of trench backfill and pavement restoration if an enclosed pipe storm sewer is installed under the street
  • Village will pay 100% of the cost of installation of trunk sewers, as defined in the plan, generally a sewer greater than 12" in diameter that provides conveyance capacity for one or more drainage districts
  • Village will pay 100% of the costs of upgrading, replacing and/or repairing collector sewers of 10" diameter or greater that serve a significant public drainage function
  • Cost of Local drainage improvements, local sewers, ditches and culverts is split 40% Village, 60% Resident
  • If curb & gutter is requested in an area that has a rural cross-section, the cost is split 50-50 between the residents and the Village
  • Roadway improvement costs and any other infrastructure repairs (sanitary sewer and water system improvements) are 100% Village obligation
  • As of late last fall, the Village Board formally adopted a new Stormwater Area Management Program (SWAMP). The new policy dramatically reduces the overall resident cost component of these projects.

Time of Concentration

Time necessary for surface runoff to reach the outlet of the drainage area from the most remote point in the drainage area. The term 'remote' is used to denote the point most remote in time, not necessarily distance, from the outlet of the drainage area.

Top of Foundation

The elevation, as measured by a surveyor, of the top of a structure's foundation. The Village of Glenview requires all new foundation construction to have between 4" and 8" of exposed foundation wall. This requirement ensures that winter and water conditions will not damage the foundation wall or otherwise seep into the structure.

Topographical Survey

Prepared by a Registered Land Surveyor or Licensed Professional Engineer, used to show the existing (and proposed if necessary) topography of the land.

Tree Preservation/Removal Plan

A plan showing all pertinent tree protection and removal information as directed by the Village Arborist. Elements of the tree plan shall be incorporated into the over site/grading Engineering plan as well.

USGS

United States Coast and Geodetic Survey

Vacant

Land on which there are no structures, or only structures which are secondary to the use or maintenance of the land itself.

Village

The Village of Glenview

Watercourse

Any river, stream, creek, brook, branch or other drainageway in or into which stormwater runoff and floodwaters flow either regularly or intermittently.

Watershed

A drainage area composed of two or more subbasins or two or more subwatersheds.

Water Tap

This form is completed as part of the permit review process in the Engineering Division, and is also used by the Water Department, in conjunction with Plumbing Worksheets to determine proper service line and meter size. This form shall be deemed necessary at the discretion of Engineering Division staff and shall be required in all instances where there is any net increase in the number of plumbing fixtures in a home.

Wet Basin

A basin designed to hold water at all times, not just during storm events.

Wetlands

Those areas where the water is at, near, or above the land surface long enough to be capable of supporting aquatic or hydrophytic vegetation, and which have soils indicative of wet conditions.

Weir

A small dam or wall across a stream to raise the upstream water level.