Small
Scale
Sewage
Treatment
Septic
Tanks - These are also used in some homes. A septic tank is an enclosed concrete box into which waste flows from the house. The organic matter accumulates at the bottom of tank whereas the water rises to the outlet pipe to flow to a distribution box.
The box is then separated into pipes which empty into the surrounding area. The tank is to be pumped out regularly as there is no absorption of the digested organic matter into the earth. Small towns collect the sewage into large ponds called oxidation lagoons.
