Wait a few days, then watch what happens. The cartoon above depicts a septic tank. Many homes have septic tanks. When houses are too far away from each other, each house treats its sewage separately in a septic tank. A septic tank is usually an underground tank that contains billions of microbes that slowly degrades sewage.
Septic tanks require a longer time to process sewage than do aerobic waste treatment facilities.
This is because septic tanks contain microbes that are mainly anaerobic, that is, they grow without oxygen. Organisms grow faster in the presence of oxygen, just the way that you can run faster when you breathe harder and consume more oxygen. In the leach field, any pathogens not killed by the anaerobic treatment in the septic tank are killed by oxygen in the leach field. When people live in cities, sewage is collected and treated in municipal sewage reactors. In contrast to septic tanks, community sewage sludge reactors are aerobic, meaning that oxygen is present.