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Infrastructure Glossary of Terms


Find out what common terms are used in relation to infrastructure projects.

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  • Apron

    The section of driveway between the sidewalk and the curb and gutter.

  • Arterial Road

    A general term for a road primarily for through traffic, usually on a continuous route.

  • Box Culvert

    A cast-in-place or pre-cast reinforced concrete box shape that is located under the embankment to drain water from one side of the road to the other.

  • Channelization

    The direction of the traffic flow into definite paths, by means of traffic markings, islands, or other means.

  • Cold Mix Asphalt

    Is produced without heating the aggregate. This is only possible, due to the use of a specific bitumen emulsion which breaks either during compaction or during mixing. After breaking, the emulsion coats the aggregate and over time, increases its strengths. Cold mixes are particularly recommendable for light traffic roads and are utilized for patching potholes, filling utility cuts, and repairing pavement that has been damaged.

  • Collector Street

    A street which serves the internal traffic movement within the city and connects with the major arterial system.

  • Culvert

    Any structure, not classified as a bridge, which provides an opening under the roadway.

  • Cured-In-Place Pipe

    A flexible tube coated with resin that is blown or pulled into the damaged pipe and inflated. The resin then hardens, creating a pipe within a pipe. Pipe diameters from 75mm to 2500mm can be rehabilitated in less than one day.

  • Detector Loop

    New traffic signal installation contracts usually include the construction of a wire detector loop placed under the surface of the pavement in the approach area of the intersection. When a motorist drives over the detector loop, the time phase for the light is affected.

  • Directional Drilling

    The action of drilling sideways under structures/roadways/streams etc to place pipes, utility lines without excavation. Generally limited to less than 30cm diameter.

  • Expanded Asphalt

    Road recycling technique that pulverizes old asphalt, adds emulsion (oil), mixes, and places recycled mat down with paver. Generally coated with a layer of fresh asphalt.

  • Hot Mix Asphalt (HMA)

    Is produced at a temperature between 150 and 190 C. HMA is a combination of approximately 95% stone, sand, or gravel bound together by asphalt cement, a product of crude oil. The asphalt is placed, and then compacted using a heavy roller, which is driven over the asphalt. Traffic is generally permitted on the pavement as soon as the pavement has cooled.

  • Hydroseed

    To spray a mixture of seed for rapid planting and erosion control.

  • Local Street

    A street or road primarily for access to residence, business, or other abutting property.

  • Maintenance

    The preserving and keeping of each type of roadway, roadside, structure, and facility as nearly as possible in its original condition as constructed, or as later improved.

  • Mill and Pave

    Approximately 50mm of old asphalt is removed by a milling machine and new asphalt is replaced in its location.

  • Mat Replacement

    All existing asphalt is removed either by milling or by excavator and repaved. Depth varies between 50mm and 250mm.

  • Private Drain Connection (PDC)

    The sewer pipe from your house to the City’s sewer main.  The PDC is typically located beneath your front lawn.

  • Raised Island

    That portion of the roadway which is raised above the roads surface by means of a curb to separate traffic traveling that area.

  • Retaining Wall

    A structure used to contain an embankment.

  • Right-of-Way

    Land acquired by purchase, gift or eminent domain in order to build and maintain a public road.

  • Stormwater Management Facilities

    They are used to gather rainfall and surface water runoff to help reduce the possibility of flooding and property damage. Through a combination of landscape and structural features, stormwater management facilities slow and filter stormwater runoff after a rainfall. The water that accumulates in stormwater ponds and wetlands is released gradually back into the natural watercourses which helps to avoid erosion of the watercourse and downstream flooding.

  • Surfacing (road surfacing)

    Material used to construct the roadway. There are four types: Asphalt, Bituminous, Concrete, Gravel.

  • Trencless Technologies

    Technology used that eliminates the need to dig, minimizes environmental damage and costs associated with underground work. Provides cost-effective sewer asset management.

  • Warm Mix Asphalt (WMA)

    Is produced at a lower temperature than hot mix. Less energy is involved and during paving operations, the temperature in the mix is lower, resulting in reduced emissions, fuel savings, and improved working conditions for the crew and earlier opening of the road.

  • Watermain Cleaning and Lining

    Hard deposits (formed by corrosion) are removed from the interior of the main and a thin layer of cement mortar is applied to the interior pipe walls to prevent deposits from reforming. This process rehabilitates existing watermains to improve water quality and flow capacity while sustaining  cost effective water.