Highway Construction FAQ


1. How long does it take to build or twin a highway?

Many factors go into building a new highway. On average, new highway construction can take anywhere from 5 to 10 years to complete, from the time the project is identified to the time the road is built. We've listed some of the steps needed to build a new road in the following PDF. Many of the steps listed may happen simultaneously, reducing the actual time it takes to build a road.

See how we build a road

The steps outlined in the PDF also apply to roads paved with concrete. Note that the length of time noted for each step may vary, depending on the length and complexity of the project. Also, some steps often occur concurrently. Weather, types of materials used for construction, location of the project, time of year a project is tendered, and available human resources can all affect timing as well. Monitoring of habitat compensation projects continue for two to seven years after construction is complete.

2. What is an Environmental Assessment?

An environmental assessment (EA) studies the impacts of a particular project on the environment as well as the effects of the environment on the project. EAs study areas including archaeology, fisheries resources, rare plants, wetlands, climate change, among many others.

Results of the EA help define the best route for the project, as well as help determine what measures need to be taken to eliminate, minimize or compensate for any predicted impacts.
  • What are the steps involved in conducting an EA?
    The department contracts one of several consulting firms qualified to conduct EAs, through a provincial procurement process. The firm then does background research on the area to determine any potential issues, field studies by experts where appropriate, and writes a report with recommendations and mitigation measures to be incorporated into the final design, tender and environmental protection plan documents.
  • What are the different levels of EAs?
    Depending on the size and location of a project, a federal EA under the Canadian Environmental Assessment Act, and/or a provincial EA under the Nova Scotia Environment Act, may be required before proceeding with construction.
    Even if a project does not meet the requirements of an EA (each Act has individual sets of criteria to determine if one is required), the department will often proceed with an EA regardless, to ensure the project is designed and constructed with the least environmental impact.
    Based on the results of the EA report, further environmental investigation and revisions to design plans also often occurs.
  • How long does it take to complete an Environmental Assessment?
    It takes approximately one to two years to complete an Environmental Assessment.
  • What kinds of things do you look at when doing an EA?
    The department studies various aspects of the environment including:
    Acid rock: rock-usually slate-that when exposed to the rain produces acid runoff which increases the acidity levels in lakes and streams that can harm or kill fish.
    Noise: the change in noise levels for properties along a highway caused by the temporary construction activity required to do the work, and the traffic volumes using the highway.
    Water supply: domestic (private wells) and municipal (reservoirs, watersheds, water lines) water supplies that may be affected by construction.
    Wetlands: these are low-lying lands commonly referred to as marsh, salt marsh, swamp, fen or bogs, that are saturated with water year-round, with poorly-drained soils.
    This type of land is usually home to a variety of water-loving plant and animal species such as cattails, rushes, bulrushes, sedges, and sphagnum moss, and trees such as alders, red maple and black spruce. Standing water may be common for extended periods of time.
    Water courses: the bed, shore, and water of every natural body of water, including all ground water.

3. Approximately how much does it cost to twin or build 1 kilometre of highway?

These costs vary continually, and are based on a variety of factors. However, in 2009, it costs approximately $3 million to twin 1 kilometre of highway. Building new highway costs approximately $3.5 million for a new 2-lane 100-Series highway plus bridges, and approximately $6 million for a new 4-lane highway.

4. What determines the cost of highway construction?

Many factors determine the cost of construction, including:
  • Contractor's operating cost (such as fuel, labour, interest rates, insurance)
  • The time of year a project is tendered
  • Time given to complete construction
  • Construction materials used
  • Amount of environmental mitigation required
  • Availability of material (shipping material in from outside the province vs. using local materials.
  • Traffic control, such as detours
  • Amount of construction being tendered
  • Design

5. What's involved in maintaining a road?

The department performs a number of maintenance activities that apply to all roads, including ditch maintenance, culvert maintenance and replacement, brush cutting, litter pick-up, shoulder repair, washout repairs, sign maintenance and bridge maintenance and repairs.

For gravel roads, regular grading and dust control application is done.

On paved roads, the department does pothole repairs, asphalt patching on one or both lanes, and centerline painting.

6. Does the department maintain all roads in Nova Scotia?

The department's highways division manages more than 23,000 kilometres of roads in Nova Scotia. This does not include roads in incorporated towns and cities, or roads owned by municipalities. We also do not maintain roads in Federal Parks, such as the Cape Breton Highlands National Park.

7. What else does the highways division of the department manage?

In addition to managing more than 23,000 kilometres of roads in the province, the highways division also maintains 4,100 bridges and operates seven provincial ferries.

8. What exactly causes potholes?

Potholes are formed differently depending on the type of road.

On gravel roads, as the finer material in the gravel is washed away, only the larger stones remain. As there is no fine material to keep those stones in place, they are knocked out by traffic and a pothole forms.

On paved roads, over time the asphalt coating begins to wear, and combined with the freeze and thaw cycle during the winter, the material is broken free of the asphalt mat and a pothole begins to form. Potholes can also form as an asphalt surface ages and cracks, allowing water to go down into the cracks and freeze and expand, breaking apart the asphalt.

Nova Scotia has a comparable amount of potholes as other jurisdictions with similar climates. This is because the freeze-thaw cycles in this climate cause a large number of cracks in the asphalt that are filled with water which freezes and expands, starting the process of making a pothole.

9. What is the Department of Public Work's budget for Highway operations?

This varies from year to year. In 2008-2009 the highway operation budget was $ 207.9 million, and the budget for highway capital construction was $ 220.4 million.

10. When are your construction and maintenance seasons?

The Department of Public Works has two seasons, a summer season for maintenance and construction, and a winter snow and ice control season

The summer construction season begins in mid-May, typically after the Victoria Day weekend, and continues into late October.

The winter maintenance season runs from November to the end of March. The summer maintenance season spans from the end of the winter maintenance season to the beginning of the following winter season. During this time we do activities including pothole filling, culvert repairs and fixing shoulders of roads.

11. Where can I find out about current construction projects in Nova Scotia?

For a list of current construction projects throughout the province, visit the highway construction projects section of our website at: /tran/highways/constructionprojects.asp