I can not see any argument that would allow the city or region to deflect any responsibility for flooding or waste water backup. The city controls the number of people that can connect and inspects every aspect of the storm water and waste water system. We can not leave thousands of residents in fear that a repeat will disrupt their lives again. Older areas need brought up to modern plumbing standards.
“Backflow preventers” are not a solution. Though they can possibly save your property, they can also easily jam on the normal material found in sewage. Even if they do engage normal use of your home will flood your basement anyway.
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