What Does Wastewater Mean?
Wastewater is water that has become contaminated after being used for domestic, industrial, medical, or commercial needs. Wastewater can contain a number of substances, such as oil, grease, and detergents.
Commercial wastewater that contains hazardous material must be appropriately treated before disposal.
Safeopedia Explains Wastewater
Water discharged from homes and businesses needs to be efficiently collected and delivered for treatment before being released into the environment. Disposing of wastewater before it has been treated can contaminate land surface and surface water.
Types of Wastewater Collection Systems
There are two main types of wastewater collection systems:
- Combined sewers, which are single-pipe systems that collect sanitary sewage and stormwater runoff. These systems are easily overwhelmed and can overflow during prolonged rainfalls.
- Separate sanitary sewers, which only collect wastewater but are built with allowance for higher waterflow and, as such, will rarely overflow.
The Importance of Treating Wastewater
Pollutants present in wastewater can have harmful effects on ecosystems and the humans who consume the water. Reasons to treat wastewater include:
- Protecting aquatic life (decaying organic matter can use up dissolved oxygen, which aquatic animals require for survival)
- Preventing overfertilization and eutrophication by minimizing the presence of excessive nutrients like phosphorous and nitrogen in the receiving water
- Reducing the presence of metals, such as lead, cadmium, arsenic, and chromium
- Preserving wildlife habitats that are teeming with a wide range of flora, fauna, and bacterial life
- Ensuring a supply of safe drinking water by managing pathogenic bacteria and harmful chemicals
- Retaining the scenic and recreational value of clean water for activities like fishing, swimming, and boating
Converting Wastewater to Potable Water
Treated wastewater can be converted to potable water using two methods:
- Indirect Potable Reuse (IPR), which involves releasing treated wastewater into a strategic environmental source (such as a reservoir or aquifer) for a specified period of time before diverting it to a treatment plant
- Direct Potable Reuse (DPR), which involves the release of purified wastewater directly into the water supply that feeds a water treatment plant, without the use of an environmental buffer (like a pond or aquifer)
A forecast by Bluefield predicts that wastewater reuse will increase by 61% by 2025, requiring US $11.0 billion of capital expenditures.