The two main reasons for collecting and treating wastewater are:
- To prevent water-borne transmission of disease
- To preserve the aquatic environment
Our present system uses water to carry away the waste products of homes and industries. With today’s technology, we are capable of treating this waste in such a manner that the receiving stream or body of water is not unreasonably affected. The natural purification process in the environment plays a role in completing this cycle.
Prevention of water-borne transmission of disease
Initial efforts to control human wastes evolved from the need to prevent the spread of diseases from infected humans. The current methods of collecting wastes and conveying wastes in underground pipes have essentially eliminated the direct exposure of wastewater to the public.
Preserving our aquatic environment
When wastes are discharged to a stream, bacteria begin to feed on this waste as part of the natural cleaning action and in the process can use more dissolved oxygen that is replenished by the natural diffusion from the atmosphere and/or by photosynthesis. Low oxygen concentrations in water interfere with the fish or other living organisms. In addition, excessive nutrients from the organic matter causes excess algae and plant growth which hampers domestic, industrial and recreational uses of the water body.
The wastewater treatment system
The Wastewater Treatment System has three major components: collection, treatment, and return to the environment.
The Collection System uses water to transport waste to the treatment system. This is accomplished through a complex network of pipes, tunnels and pumping stations.
Once at the Wastewater Treatment Facility, wastewater flows through a series of processes that gradually remove the solids and renders it suitable for return to the environment.
Treated wastewater or “effluent” is returned to the environment, usually a water body at the desired level of treatment while solids extracted from the various processes can receive further treatment or stabilization before being recycled back to the earth.