Southwest Clean Water Plant Treatment Process

From Waste to WaterTests are performed in the lab.

1. Collection

The water that goes down our drains and toilets collects in the sewer where it’s carried to one of our City’s two award-winning treatment plants.

2. Head Works

All large solid objects - such as food scraps, flushable wipes, toys, and more - are screened out, collected, and transported to the landfill. 

3. Primary Clarifiers

Larger insoluble materials are settled out and grease separated from the remaining wastewater in our primary clarifying tanks. Solids settle to the bottom of the tank and greases rise to the top. 

4. Aeration Basin

This basin churns wastewater to increase oxygen levels and create an ideal environment for the employment of naturally occurring microorganisms to remove phosphorus and organics in the effluent. 

5. Secondary Clarifiers

The secondary clarifiers, much like the primary, are used to separate the treated water from the other materials. In this instance, the microorganisms settle to the bottom and are recycled back into the aeration basins or sent to the anaerobic digesters. 

6. Polishing Filters

The polishing filters are a final stage of filtration that push remaining solids back to the head of the process and allow treated water through. 

7. UV / Ozone Treatment

Just before the treated water is released back into our streams, it is purified and disinfected by passing through UV light or through the diffusion of ozone into the treated water. 

8. Digesters

The excess and inactive microorganisms from step 5 are pumped to the digesters where they are broken down, creating methane for energy to help power the plant and solids which are further treated to remove excess water for future reuse.

9. Testing & Discharge

Testing throughout the process ensures the water being discharged into our waterways protects our public health and the environment. 

How the Treatment Plant process works


Detailed description of treatment process