The average age of the stock of wastewater treatment facilities peaked at 19.5 years in 1999 in Newfoundland and Labrador. Although investments were much lower in 2007 than at any time since 1999, its average age was reduced to 17.6 years in 2007. This fall is mainly attributable to the discarding of older investments from the gross stock base.
In terms of the percentage of estimated useful life, there has been a general trend toward ageing of wastewater treatment infrastructure both nationally and in Newfoundland and Labrador, especially since 1980. In 2007, the stock of wastewater treatment facilities had reached 62% of their estimated life, almost equal to the national average.