Wastewater FAQ's

Wastewater FAQ's

What is wastewater?
Wastewater is the polluted form of water generated from rainwater runoff and human activities. It is also called sewage. It is typically categorized by the manner in which it is generated—specifically, as domestic sewage, industrial sewage, or storm sewage (stormwater).
How is wastewater generated?
  • Domestic wastewater results from water use in residences, businesses, and restaurants.
  • Industrial wastewater comes from discharges by manufacturing and chemical industries.
  • Rainwater in urban and agricultural areas picks up debris, grit, nutrients, and various chemicals, thus contaminating surface runoff water.

How is wastewater formed? 

Domestic Wastewater :  is wastewater  formed by a number of activities such as bathing, washing, using the toilet, and rainwater runoff. Wastewater is essentially used water from water use in residences, businesses, and restaurants.
Domestic wastewater,  is relatively easy to treat. 

Some wastewaters are more difficult to treat than others. For instance, industrial wastewater can be difficult to treat due to its high strength that discharges by manufacturing and chemical industries.

There are a number of ways in which wastewater can cause pollution problems, considering not all waste makes it to wastewater treatment plants. 


What are the common pollutants present in wastewater?
Wastewater contains a wide range of contaminants. The quantities and concentrations of these substances depend upon their source. Pollutants are typically categorized as physical, chemical, and biological. Common pollutants include complex organic materials, nitrogen- and phosphorus-rich compounds, and pathogenic organisms (bacteriaviruses, and protozoa). Synthetic organic chemicals, inorganic chemicals, microplastics, sediments, radioactive substances, oil, heat, and many other pollutants may also be present in wastewater.
How is wastewater processed at a sewage treatment facility?
Sewage treatment facilities use physical, chemical, and biological processes for water purification. The processes used in these facilities are also categorized as preliminary, primary, secondary, and tertiary.

Preliminary and primary stages remove rags and suspended solids.
Secondary processes mainly remove suspended and dissolved organics.
Tertiary methods achieve nutrient removal and further polishing of wastewater.
Disinfection, the final step, destroys remaining pathogens. T
he waste sludge generated during treatment is separately stabilized, dewatered, and sent to landfills or used in land applications.
Why is wastewater resource recovery important?
Wastewater is a complex blend of metals, nutrients, and specialized chemicals. Recovery of these valuable materials can help to offset a community’s growing demands for natural resources. Resource recovery concepts are evolving, and researchers are investigating and developing numerous technologies. Reclamation and reuse of treated water for irrigation, groundwater recharge, or recreational purposes are particular areas of focus.