The average age of this asset was higher in 2006 than at any time since 1967. The lowest average age was in 1981 at 14.3 years. Low investment rates in this asset have resulted in a steady ageing trend, reaching an average 19.7 years in 2007. Sewer systems are the second most important public asset in Nova Scotia. In 2007, they accounted for 12% of the total investment in public infrastructure.
Although there has been a long-term trend towards ageing of sanitary and storm sewers since 1980, both nationally and provincially, this trend has been more pronounced in Nova Scotia in recent years. By 2007, sanitary and storm sewers had reached 59% of their estimated useful life, well above the national average of 53%. This put the province in the fourth place in terms of oldest sewer systems among provinces.