Wastewater Treatment Plants Take Many Steps To Treat Wastewater

The water we flush down toilets, pour into sinks or wash with flows down drains and into sewers. This water is called wastewater and it contains a lot of contaminants. It must be treated before it is released back into the environment so that it doesn't pollute drinking water sources.

Wastewater treatment plants take many steps to treat wastewater before it is safe to release into rivers, lakes or oceans. Most pumps for wastewater goes through a series of processes called primary, secondary and advanced treatment. These steps remove or reduce a wide range of pollutants.

At the primary level, screens and settling tanks remove solids from wastewater. These steps are crucial, because they keep large debris, sticks and garbage from entering the treatment plant. The solids are then disposed of at a landfill. Next, a grit chamber removes small cinders and other materials that could damage treatment equipment. The wastewater then flows through screens with openings less than one millimetre across, where rags and other larger debris are removed. Finally, the wastewater enters a sedimentation tank where it settles for several weeks. This process allows bacteria to eat the organic waste in the wastewater, converting it into carbon dioxide, water and energy. This process also protects the dissolved oxygen levels in receiving waterways.

Toxic substances in the wastewater require chemical treatment. This is done in a series of steps called primary, secondary and sometimes tertiary treatment. Toxic soluble metals, such as lead or copper, are found in the wastewater of industries that manufacture and repair automobiles, steel, paper and textiles. These substances need to be removed in order to protect ecosystems that fish and other species use for food. The metals are separated from the wastewater using methods like ion exchange, which lowers their mineral content. Chemicals are also used to break down or inactivate toxic bacteria in the wastewater.

This step is the most important part of wastewater treatment. Chemicals are added to the water to kill any remaining harmful bacteria, viruses and other microscopic organisms. The resulting disinfected effluent is known as treated effluent or tertiary treatment effluent.

In many communities, treated wastewater is recycled and put to good use. This water can be used for irrigation, replenishing groundwater supplies and supplying drinking water to residents. It can also be used to help meet water demands in emergency situations.

For example, Water and Wastewater, recycles its treated municipal wastewater to irrigate city landscapes and playing fields, water a public fish pond, and supply drinking water to fire hydrants. The town also uses highly-treated wastewater to reduce the amount of freshwater needed for its industrial activities and help restore downstream shellfish beds. This type of wastewater reuse is called water reclamation. Water reclamation is an important tool for helping communities prepare for climate change impacts such as droughts and heat waves. It can also enhance source diversity and improve water security. In addition to providing a new source of water for cities, water reclamation can be beneficial to farmers by increasing crop yields and nutrient content.