Wastewater backup flooding usually occurs when the domestic sewer system overflows as a result of inflow and infiltration forcing stormwater from severe rainstorms back up through the private-side laterals that connect a household’s plumbing system to the municipal domestic sewer system. Specifically in Saskatoon, weeping tile systems for a large number of homes are connected to basement floor drains. This was identified as the primary cause of rainwater entering the wastewater sewer system during storm events. One simple solution to this problem is a backflow protection valve, essentially a one-way gate installed in the sewer lateral that allows sewage to flow out from the house into the wastewater sewer system but not the reverse. Many older homes do not have such a safeguard in place, leaving them vulnerable to sewer backup. While relatively cheap to install in new development, renovating existing homes to include a sewer backup valve is costly and frequently difficult to retrofit for the average homeowner. Additionally, since weeping tile systems were the primary cause of the basement flooding homeowners were also required to disconnect their home’s weeping tile from the floor drain by installing a sump to expel this water outside the house. The City of Saskatoon opted for a an incentive-based system to encourage this type of renovation by covering most of the costs. It was created as a response to the damaging floods in 2005, 2007, and 2010. These events created the impetus for the program and also helped to inform the planning and execution of it. The first step the city undertook was to create a map of all of the homes affected by sewer backup flooding in the wake of rainstorm. This map allowed them to precisely target the most at-risk areas. This precision targeting was an essential component of the success of the Flood Protection Program. Historically, many municipalities have found it difficult to get high levels of uptake on flood protection renovations, even with financial incentives. The City of Saskatoon, by focusing specifically on high-risk areas, was able to target those homeowners who stood to be the most heavily impacted and, therefore, had the highest incentive to participate.
In 2005, the City of Saskatoon enacted a temporary Flood Protection Program to help protect against sewer backup flooding by providing financial assistance towards the installation of protective plumbing features such as sump pumps and backwater protection valves. This program was later expanded after flooding struck the city again in 2007 and later in 2010.