On the subject of wastewater, we typically think of the sewage system. On the other hand, it is actually more than that. This consists of domestic water too that’s produced from disposals, sinks, washers and showers. Not only that, but wastewater may also include any used water as well as water-carried solids from the community that is flowing to the treatment plant like:

  • Industrial water
  • Surface water and;
  • Stormwater

Believe it or not, 99% of wastewater is simply dirty water. The remaining 1% is chemicals, fats, nutrients, solids and several other pollutants.


Majority of the sewer systems are operating via gravity flow. This means, it pulls the wastewater to the treatment facility or plant. It will enter the plant first at the headworks and then, it passes through preliminary treatment that’s called screening. This is where big objects will be trapped and then removed for landfill disposal.

Once the screening is done, wastewater will then enter the grit chamber in order to remove the heavier solids similar to gravel, sand, rocks and all other materials which will eventually sent to the landfills as well for proper disposal.

Right after the preliminary treatment, the wastewater is going to flow to the primary sedimentation basin in which some solids will be separated from water. In this stage, the small and heavy particles similar to beans, corn and the likes will sink to the bottom as sludge while the lighter materials similar to oils and fats float to the top for skimming. Both the skimmed and primary sludge materials are disposed properly.

Aeration and Sedimentation

The wastewater that leaves the primary treatment will then enter the next treatment process, which is divided into two phases.

  • 1st phase – this is called aeration where the wastewater is mixed with air as well as cultivated microorganism that’ll consume the suspended organic matter like human waste, food particles.
  • 2nd phase – wastewater will go through another sedimentation process in which the microorganisms referred to as activated sludge will be removed from the treated wastewater.

Activated sludge will be returned to oxidation ditches to be able to consume more organic matter or it’ll be diverted to digestion process as waste where it’s treated and then, dewatered to be able to eliminate pathogens and vector attraction.

The process is not entirely known to people which is why entities doing such important tasks should consider to buy backlinks and post articles to their website to inform people of the importance of proper waste segregation.