The average age of sanitary and storm sewers reached its all-time high of 17.6 years in 1997. Several years of stronger investments thereafter lowered the average age to 16.4 years in 2002. Since then, slower investments have caused an increase in age to 16.9 years in 2007.
The provincial rate for estimated useful life has fluctuated closely with national rates over many years. By 2007, sewer systems in British Columbia had reached 50% of their estimated useful life, compared with 53% nationally.