Why is a deflector panel or drop bowl necessary?


Deflector panels and drop bowls are both used to reduce the amount of turbulence in the wet well. Turbulence can have several adverse affects on the lift station. First, unimpeded water, cascading down onto the pumps, can damage them over time. This is especially true with pump cables, which are normally mounted on the top of the pump. If the water breaks or interrupts the connections, power can be cut from the pumps. Cascading water also creates a “waterfall effect,” where air is pushed down into the water. The air in the water can then get pumped, significantly increasing the overall pump wear – especially on the impeller. The air bubbles leave pocking marks on the surface of the metal as they get passed through. Another problem cascading water creates is faster off-gassing in sewage. Excess hydrogen sulfide gas will eat away at the concrete in the wet well. Finally, cascading water disrupts the water’s surface, making it difficult for level sensing devices to function reliably. Floats are especially sensitive to this when controlling functions like pump starts and stops. Waves and turbulent conditions can incorrectly trigger the devices to start or stop pumps cycles. Deflector panels and drop bowls are two low-cost solutions that drastically reduce or eliminate the impacts of cascading water.