Types of Waste Water & Treatment

The United States uses billions of water every day in both household uses and commercial. Many Americans don't stop to think where this waste water goes as it flows down the drain. Water from homes across the nation, as well as runoff from storms and other activities that use street drains creates large amounts of waste water every day, which must be treated in order to prevent serious harm to the environment.

Household and Commercial Waste Water

• One of the leading sources of waste water comes from households across America. Each time you flush a toilet, take a shower, wash clothes, or run your dishwasher, you're creating waste water that needs to be treated before it can be reused or sent back into the environment. Household waste water consists of anything that contains human sewage, soap, food scraps, chemicals, oils or other substances that get washed down the drain or flushed down the toilet. Commercial installations also create similar waste water in the same ways, but typically in higher volumes.

Storm Runoff

• Storm runoff is another substantial source of wastewater. Storm runoff occurs anytime there is a lot of rain, or during spring when snow melts and runs off into the storm water system. When you wash your car or over-water your lawn, this also counts as storm runoff. Unfortunately, the moving water from these sources carries along with it harmful substances from roofs, parking lots and streets. It also carries toxic substances like pesticides and herbicides.

Effects

• Waste water can create problems both for human health as well as general environmental health. For example, phosphates from dish-washing detergents and other soaps can make their way into lakes and rivers, causing an overgrowth of algae, which decreases available oxygen for fish and other aquatic life. Waste water often also carries disease, especially sewage water, which requires substantial processing before the water can be released back into the environment. Contaminants can also cause problems if they seep into ground water supplies, affecting drinking water, or into lake, river or ocean water, which can kill or contaminate fish.

Treatment of Waste Water

• Waste water needs to be treated in order to remove the majority of solids within the water. Solids decay in water, and the chemical process of decay takes oxygen from the surrounding water, which is necessary for aquatic life to live. Waste water treatment plants remove the floating solids in the water with 60 percent removed during primary treatment, and up to 90 percent removed in the secondary treatment, according to the United States Geological Survey. A tertiary treatment may also be used for even better results. The remaining water, called effluent, is then aerated to replace oxygen lost during decay and released back into the environment, where nature begins returning the water back to its original clean state.