Methods for Safe Sewage Disposal;- Because they can end up in the environment, all disposable items should be placed in a bin or bag rather than flushed down the toilet. Tampons and condoms should be wrapped securely and thrown in the trash. Put dental floss, bandages, plasters, and cotton buds in the trash.
One of the main causes of coastal contamination worldwide is the discharge of sewage. Human waste, together with other organic material, heavy metals, herbicides, detergents, and petroleum compounds, are released by sewage outfalls close to coastal areas.
Eutrophication may result from the nutrient enrichment of local waters by organic waste nutrients, detergents containing phosphate, and agricultural and horticultural runoff.
Methods for Safe Sewage Disposal
Definition of Sewage
- Sewage is the mixture of liquid, faeces, toilet paper and food wastes produced by people
- The liquid in sewage includes urine and wastewater which comes from the toilet, the kitchen, bathroom and laundry
- Sewage contains lots of disease-causing germs and parasites
- Sewage is treated to get rid of as much of the solid matter as possible
The remaining liquid is called effluent.
Importance of sewage disposal
- Sewage disposal is the process in whichsewage is transported from inhabited areas to sewage treatment plants
- This is important to prevent people from getting infection caused by microorganisms found in the sewage
Importance of safe sewage disposal
- Protects public health from diseases
- Prevent water pollutionfrom sewage contaminants
- Remove sources of contaminants from the environment to make it safe.
Methods for Sewage Disposal.
There are main two types of sewage disposal systems which are:
- On-site systems
- Sewageor effluent systems
1. On-site sewage disposal systems
- It treats the sewage in a septic tank so that most of the sewage becomes effluent and is disposed of in an area close to the house or buildings
- Example of an on-site disposal system consists of a septic tank and leach drains
- All the liquid waste from the toilet, bathroom, laundry and sink goes into pipes which carry it to aseptic tank
- The effluent from the tank is then disposed of through effluent disposal drains often referred to asleach or French drains
- Both of these methods of disposing of liquid waste areon-site disposal systems. They must be installed and maintained properly.
In these systems, the effluent is soaked into the surrounding soil.
On-site disposal systems cannot be installed in all situations. For example, they cannot be installed:
- In areas that flood regularly
- In areas that have a high water table (that is, where the underground water is close to the surface)
- Where the amount of wastewater to be disposed of is large
- Near to drinking water supplies
2. A sewage or effluent (wastewater) system
- It disposes of the effluent from a community at a central place usually called asewage lagoon or effluent pond
- In this method the effluent from the community is carried by large pipes to the lagoon.
- These pipes serve all the houses and other buildings in the community
- Before disposal, the sewage is treated. This involves holding the sewage in a closed or open space for a few days to allow fluids and solids to separate and bacterial action to turn the sewage into safer form
- The sewage can be treated:
- In a septic tank at each building
- Just before the lagoon in a large septic tank or macerator system, or
- In the lagoon itself
Key Points
- Sewage is a mixture of excreta, water and other materials
- Sewage disposal is important to make the environment free from pollutants and diseases
- There are two main methods for sewage disposal; on-site and sewage system.
References
- Basset, W.H. (1992). Clay’s Handbook of Environmental Health (16th ed). London: Chapman and Hall
- Nyamwaya, D. (1994).A Guide to Health Promotion through Water and Sanitation, Nairobi: AMREF
- Wood CH., Vaughan JP., &de Glanville H (1997).Community Health (2nded). Nairobi: AMREF