Water closet/Flush toilet

• Is part of the water borne sewage
• This means that wastes from the toilet are carried by water to a place where it is processed
• This is very common in urban homes  and places where there is a water supply
• It is most suitable in places where the population is high
• The Water Closet is complex and expensive to install and operate

Water Closet. Image credit metaefficient.com

• It consists of a bowl of earthenware, plastic or fiberglass
• This makes the seat clean and attractive and easy to clean
• The bowl is designed so that there is a water seal (a curved/looped part in the seat)
• The seal always contains water to prevent bad smell from the main sewer pipeline from escaping into the room
• The seat as a lid which must closed during the flashing process to prevent splashing
• The sewage from these Water closets/Flush toilets are disposed of in three ways:

1 Cesspits

A cesspit

• Also known as the pit
• It is made up of a single underground tank, which collects raw sewage from flush toilets
• Water seeps through the walls of the pit into the ground
• Bacteria in the tank break down wastes
• The pit fills up after some time and must be emptied by waste removal companies

2 Septic Tanks

A septic tank

• Is a modification of the cesspit
• It is made up of two chambers
• In the first chamber which is also known as the decomposition chamber
• Anaerobic bacteria are actively involved
• They slowly decompose the waste
• In the second chamber the waste is sprinkled over stones,
• Jelly forms, ciliates and aerobic bacteria are involved
• Ciliates feed on bacteria and break down organic substances such as urea
• When the water leaves the second tank it seeps back into the ground
• Sludge has to be regularly removed from the first tank
• It is often used as organic compost and manure

3. Centralised Sewage treatment works

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