Study: The age of Canada's public infrastructure

1963 to 2003

The average age of the four main components of Canada's public engineering infrastructure has stabilized in recent years after 20 years of steady increases, thanks to higher investment.

A new study examines the aging, from 1963 to 2003, of the four main components of engineering infrastructure owned by governments: roads and highways, sewer systems, wastewater treatment facilities and bridges.

Combined, they comprised 80% of all engineering infrastructures owned by federal, provincial, territorial and municipal governments in 2002.

The study found that in 2003, three of the four components had passed the halfway mark of their so-called "service life," for all levels of government.

Wastewater treatment facilities, the oldest infrastructure, had 63% of their useful life behind them in 2003. Bridges, the youngest infrastructure, had reached 49% of their useful life. Roads and highways had reached 59%, and sewer systems 52%.

The study supports, to some degree, the widely held view that Canada's infrastructure has aged. However, the aging trend has stabilized in recent years. In 2003, average age actually diminished slightly, thanks to increased investment by the various levels of government.

The steady pace of urbanization and population growth, among other factors, has necessitated huge amounts of investment, particularly for roads and sewers. This addition of new infrastructures contributed to stabilize the average age.

This stock of government-owned engineering infrastructure is huge, worth an estimated $154.8 billion in 2002. It has a tangible impact on the economic performance of Canadian businesses, let alone the pleasure of driving on good roads and bridges.

During the past 40 years, growth in infrastructure has accounted for just under one-fifth of productivity gains in the business sector, a measure of the efficiency with which inputs are used to produce goods and services.

First decline in average age in 30 years

Overall, the average age of the four main components of engineering infrastructure considered in this study (roads and highways, sewer systems, wastewater treatment facilities and bridges) increased substantially between 1973 and 1999. Then their average age was stable until 2002, before declining slightly in 2003.

In 1973, on average the four components taken together were an estimated 14.7 years old. By 1999, this average had increased to 17.5 years and stayed at that level until 2002. In 2003, it edged down to 17.4 years.

Most of the aging occurred between the mid-1970s and the late 1980s. In the following years, the aging continued, but at a slower pace.

A key factor in the recent slower pace of aging is a huge jump in investment in roads and highways, which has tended to rejuvenate this transportation network.

The network has started getting "younger" as investment has risen. On the other hand, bridges and wastewater treatment facilities have been aging almost without interruption since 1977, while the age of sewer systems has fallen slightly since 2001.

Two out of three levels of government saw the age of their infrastructure, covered by this study, decline in 2003. Provincial and municipal infrastructure got younger, while the average age of federal infrastructure remained virtually unchanged.

Nevertheless, federal infrastructure was already older than provincial and municipal infrastructure.

Provincial infrastructure aged the most, its average rising from 14.4 years to 18.8 years between 1963 and 2003. The age of municipal infrastructure also increased, though to a lesser degree.

Urbanization and population growth

There are many factors contributing to investment in infrastructure: population growth, urbanisation, urban sprawl, standard of living and car usage.

The strong population growth in urban areas has probably been a primary factor in shaping major changes in infrastructure. It undoubtedly accounts, in part, for the higher growth in the discussed components of infrastructure and the expanding role of municipal governments.

Urban growth goes hand in hand with the need for infrastructure. As the municipality grows, the need for infrastructure grows.

The average age of municipal infrastructure is a function of the development of new suburbs, which are made up of recent infrastructure, as well as the infrastructure in older neighbourhoods. The development of new suburbs may decrease the average age of the municipal infrastructure even if nothing is done to offset the aging of infrastructure in older parts of a city.

Road network: Recent decline in age

The road network is by far the largest component examined in this study, accounting for two-thirds of the total value.

The road network started getting younger in 1995, following a period of steady aging from 1974 to 1992. High levels of investment have rejuvenated the road network. However, they have not been enough to bring the age of roads and highways down to what it was in the early 1960s.

The average age of roads and highways rose from 14.1 years in 1974 to 17.0 years in 1992 and then edged down to 16.6 years in 2003.

Because the average service life for roads and highways is 28 years, this means that by 2003, this network already had over 50% of its useful life behind it.

The sewer system experienced the highest growth in investment, and this is the reason that the age of the system has remained steady over the years.

Between 1963 and 2003, investment in sewer systems more than doubled (+156%) because of urbanisation and population growth. Average annual investment rose from $580 million between 1964 and 1973 to $1 billion between 1994 and 2003 (in 1997 constant dollars).

Municipal sewer systems have been getting younger since 1997, as municipalities have been investing heavily in this type of infrastructure. Between 1997 and 2003, municipal governments accounted for more than 95% of the total investments. Provincial and federal sewer infrastructures are much older than municipal.

Of all four components, wastewater treatment facilities were closest to the end of their service life. The average age of treatment facilities was 18.3 years in 2003, which represented 63% of their estimated service life of 29 years.

Municipal governments were responsible for more than 70% of the stock of wastewater treatment facilities and accounted for more than 95% of the corresponding investment between 1997 and 2003.

Bridges were the youngest of the four infrastructure components relative to their useful life in 2003. They had reached only 49% of their useful life, with an average age of 22.7 years over a service life of 46 years.

By 2003, federal and provincial bridges had passed past the halfway mark of their useful life; 57% in the case of federal bridges and 53% in the case of provincial. In contrast, municipal bridges were younger, and had only 41% of their useful lives behind them.

Definitions, data sources and methods: survey number 2803.

The analytical article "The age of public infrastructure in Canada" (11-621-MIE2006035, free) is now available online in the Analysis in Brief series.

For more information, or to enquire about the concepts, methods or data quality of this release, contact Valérie Gaudreault (613-951-1165), Investment and Capital Stock Division.