Why your Wichita basement backs up when it rains hard

A basement floor drain that backs up during heavy rain is usually not a blockage in your line. It is the municipal main surcharging, filling faster than it can discharge, and finding the lowest opening in the system to relieve into. In a Wichita basement, that opening is your floor drain.

The device that prevents it is a backwater valve, installed on the lateral, which closes automatically when flow reverses. It is a permitted installation and it is genuinely effective. Homes that have flooded this way twice are the ones that should have one.

There is a related issue worth knowing about. Downspouts and sump discharge piped into the sanitary sewer add stormwater to a system that was not sized for it, and in many places that is prohibited. If your sump discharges into a floor drain, that is worth changing regardless of whether it has caused you a problem yet.

If the backup happens without rain, that is a different problem and it points to a blockage in your own lateral rather than the main. A camera inspection separates the two quickly.