Most people know that their sewage system brings waste products to a facility somewhere and treats them, but you may not know exactly how this treatment occurs. There are several methods of treating sewage that range in popularity. Sewage can be treated in a septic tank or even within a pooled area of sewage water.
Onsite Disposal and Treatment
Onsite disposal systems will take the liquid waste from the laundry room, sink, toilet, and bathroom and bring it through pipes to the septic tank. The tank then brings effluent via disposal drains before it is soaked up by the surrounding soil. This isn’t an option for areas near drinking water supplies, those that flood regularly, or where the water table is high. It also only works for smaller amounts of wastewater in the sewage system.
It is more likely to have a larger treatment facility that takes care of the sewage and waste from a larger area. The water in this area will first go through a screening process where large items, like bottle tops, rags, and face wipes, are removed, so the equipment doesn’t clog. Grit that has entered the sewer is removed by special equipment at this point. After this, the water enters a large tank for settling. The solids settle at the bottom and are known as “sludge”.
The sludge is pumped away for extra treatment, and clean water is removed to large, rectangular tanks called aeration lanes. The system pumps in air, so bacteria break down any remaining sludge. Finally, the water enters a settlement tank, where the last of the sludge settles before the water enters a river or another natural body of water.