Meaning of Sewage and Refuse – JSS1 Physical & Health Education Lesson Note (First Term)

Sewage is liquid waste, made up of waste from the human body and used water carried out of houses by sewers. Refuse is solid, unwanted waste such as paper, leaves, ashes and dead animals. Both must be disposed of properly to prevent the spread of infection and health hazards in society.

Behavioural objectives

By the end of the lesson, students should be able to:

• define sewage and refuse;
• name diseases that sewage can cause;
• describe methods of refuse disposal;
• describe methods of sewage disposal;
• explain why bucket latrines should be discouraged.

What is sewage?

Sewage is the liquid waste from domestic, industrial and commercial effluents. It is the mixture of waste from the human body and used water that is carried out of houses by sewers.

Sewage carries bacteria which can cause diseases such as cholera, typhoid and dysentery.

Sewage disposal is the way and manner of getting rid of liquid wastes.

What is refuse?

Refuse can be defined as all solid wastes in the house, such as pieces of paper, leaves, garbage, ashes, rubbish and dead animals. It can also be defined as unwanted, discarded, non-liquid materials coming from various activities of humans.

Refuse disposal is the way and manner of getting rid of solid wastes. Refuse should be properly disposed of to prevent the spread of infections and health hazards in society.

What are the methods of refuse disposal?

There are many methods of refuse disposal. These are the following:

1. Open dumps

In this method, refuse and garbage are deposited on the land. The dumps serve as breeding places for flies, cockroaches, rodents and mosquitoes.

2. Incineration

This is the burning of refuse in a controlled cabin. The refuse is deposited inside a house-like facility and the materials are burnt, with oil, coal or gas serving as fuel.

3. Composting or decomposition

This method consists of disposing of refuse in a shallow pit that is covered with soil. The refuse is allowed to decay and later mix with the soil. The product is called humus soil and is used as manure or fertiliser.

4. Sanitary landfill

A sanitary landfill is also known as controlled tipping. It is a big hole dug in the ground where refuse from the community is emptied. The refuse is then covered with soil or ashes to prevent flies and rodents from getting access to the refuse inside.

5. Open burning

What are the methods of sewage disposal?

1. Water system: This is a modern system used where pipe-borne water is available, together with a septic tank. It is common in many modern homes.
2. Bucket latrines: Faeces and urine are collected inside a bucket. This method is unhygienic and should be discouraged. Burying faeces is also common with this method.
3. Septic tank latrines: A septic tank is an underground tank built away from the building. Sewage flows into it through a pipe, aided by water.
4. Pit latrines: The sewage falls into a pit or hole in the ground, usually covered with a lid. This keeps away flies and cuts down odour. Pit latrines should be built away from wells and houses.

Evaluation

1. Name three diseases that sewage can cause.
2. What is the product of composting called, and what is it used for?
3. Describe a sanitary landfill.
4. Why should bucket latrines be discouraged?
5. Why should pit latrines be built away from wells and houses?

Assignment

1. Explain the meaning of sewage and refuse.
2. Differentiate between sewage disposal and refuse disposal.
3. List two methods of sewage disposal.
4. Itemise two methods of refuse disposal.