Solution
WaStop® Inline Check valve
A DN1200 WaStop was installed inside the stormwater outfall to allow flood water to flow into the river, but prevent it from flowing back up the stormwater outfall when river levels rise. This gave local residents peace of mind, knowing the town would not be affected by flooding due to backflow.
Thanks to Canplast Switzerland for supplying this information. www.canplast.ch