Wastewater - What Is It?
Wastewater comes from ordinary living processes: bathing, toilet flushing, laundry, dishwashing, etc. It comes from residential and domestic sources.
Commercial wastewater comes from non-domestic sources, such as beauty salon, taxidermy, furniture refinishing, musical instrument cleaning, or auto body repair shops. This wastewater may contain hazardous materials and requires special treatment or disposal.
*These educational materials only cover residential (domestic or private) wastewater treatment.
There are two main types of residential wastewater treatment:
- A lagoon system places wastewater in a shallow open pool. Treated effluent from the lagoon is introduced into the environment through slow evaporation
- A septic system places wastewater in an underground tank. Treated effluent from the tank is introduced into the environment through a drainfield.
Wastewater is broken into two categories, depending upon the source.
1. Gray water: Gray water is from showers, baths, whirlpool tubs, washing machines, dishwashers and sinks other than the kitchen sink.
2. Black water: Black water is from toilets and kitchen sinks.
- Definitions vary from state to state : Some states define blackwater as wastewater only from toilets.
Septic Systems
Lagoon Systems
Wastewater Treatment Requirements
- All wastewater must be treated.
- It cannot be discharged to the land, or to surface or groundwater.
- It cannot be used for irrigating a lawn, to fill a pond, run through a pipe to a nearby stream, or dumped to a cesspool.
- You may hear of gray water being used for irrigation in other (arid) states. Even in those states, this must be treated and disinfected prior to use. This is NOT allowed in Nebraska.
What is in Wastewater?
Wastewater is 99.9% water.
The other 0.1% is what is cause for concern. That 0.1% includes:
- Nutrients: Phosphorous and Nitrogen
- Fats, oils, grease: cooking oils, body lotions
- Pathogens: disease-causing bacteria and viruses
- BOD-biochemical oxygen demand. BOD is a measure of oxygen needed by aerobic bacteria to break down organic matter. A higher BOD means there is more organic matter that needs to be broken down.
- Other solids
Visit the links above to learn more about your type of residential wastewater treatment system and tips on how to maintain it.
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