Backwater valves in new construction is fine, but it's not going to help anybody else." Chandler argued a number of city streets have always flooded, even way back to when he was a kid.

A backwater valve prevents sewage from coming into a house when the sanitary sewer gets inundated with stormwater that pushes itself back up the pipe. "The full pipe starts working its way ...

Ed Buchan, with the City of Raleigh Department of Public Utilities, explains why each home needs a backwater valve to prevent sewage from backing up into the house.

“Every time I meet with a group, I take applications.” Des Moines pays up to $1,500 — which is often 100% of the costs — for residents to install what is known as a "backwater valve.” ...

The valve ensures sewage can only flow in one direction, out of the home during sewer surcharges. Backwater valve installations can range in cost from $1,700 to $3,000.