May 27, 2011 by Canadian Underwriter
Backflow valves are 85% effective in eliminating sewer backup, according to Galen Heinrichs, stormwater utility manager with the City of Saskatoon.
Moreover, in that 15% of instances in which a home experienced some sewer backup despite having a backflow valve, the backflow valve was nevertheless 96% effective in reducing damage from the event, said Heinrich.
Heinrich spoke at the Institute for Catastrophic Loss Reduction’s Basement Flooding Symposium held May 26 in Toronto.
Beginning in 2003, the City of Saskatoon implemented a bylaw requiring all new homes to have a backwater valve. Around the same time, the city implemented a flood protection program to help mitigate basement flooding and sewer-backup issues in high-risk homes.
Homes deemed to be at risk were given an opportunity to upgrade their plumbing with a sump pit and a backwater valve; the city reimbursed the homeowner 100% of the cost. The program was offered three times. In 2005 and 2007, the city paid a maximum reimbursement cost of $2,500. In 2010, the limit was increased to $3,000.
Roughly 50% of the at-risk homes participated in the program, which accounted for roughly 700 homes, Heinrichs said.
When Heinrich’s department conducted a survey to determine why the other 50% had not participated, there was no overarching reason. Individual responses included that the backup was a random event, the problem rested with the city and not with the homeowner, and that the homeowner did not want to deal with the mess that would result from installation.