Marshall Municipal Utilities

Aeration Basins

The Aeration Basins are where the biological process takes place. Although in the aerial photo it looks like there are four basins, there are actually only two. The basins are peanut shaped, and the wastewater flows freely between the two halves.

Before the stream enters the basins, it goes through the splitter structure which does nothing but divide the stream between the two aeration basins.

We have fourteen, 100 HP Aerzen blowers that serve the two basins, seven each. Also housed in the two structures are the motor units that run the blowers, bridges, and two O₂ minimizers with related electronic equipment. The minimizer on each basin continuously and automatically tests the wastewater for DO and turbidity. These test results cause the blowers to cycle on and off as needed. The basins are equipped with approximately 3,000 fine-bubble air diffusers located both suspended from the traveling bridges and mounted along the walls.

From here, the wastewater flows to the Final Clarifiers for further treatment.