Non-return valves
Reasons to install backflow prevention protection.
The causes of backflow
Back flow from the public sewer system is mainly caused by:
- overall under-sizing of the public sewers
- high peak flows in stormwater sewers or combined sewers due to short but intense rainfall (climatic trend throughout the world)
- increase of surface water runoff due to new construction (growing territorial urbanization), causing greater volume of flow
- overflow due to peaks of simultaneous flow in built up areas
- malfunctions or blockages downstream from the grid.