Water Treatment in
” Sanitation” refers to all conditions that affect health, especially with regard to infection and specifically to the disposal of excreta, sullage and refuse from houses, hospitals and Universities. In 1950, the WHO Expert Committee on Environmental Sanitation defined environmental sanitation as the control of community water supplies, excrete and wastewater disposal, refuse disposal, vectors of disease, housing conditions, food supplies and handling, atmospheric conditions, and the safety of the working environment.
Open defecation is a serious health hazard and is responsible for surface and groundwater contamination and transmission of water borne diseases. Hence, today, sanitation is generally referred to sanitary and safe disposal of human waste or excreta. Safe disposal of excrete is of fundamental importance, not only for the health of the community, but also because of the social and environmental benefits it brings. The UN General Assembly declared the year 2008 as the International Year of Sanitation to highlight the importance of sanitation. The goal is to raise awareness and to accelerate progress towards the Millennium Development Goal (MDG) target to reduce by half the proportion of the 2.6 billion people without access to basic sanitation by 2015
Advantages of Sanitation
Following are the important advantages of sanitation
- Sanitation reduces cholera, diarrhea, dysentery and worm infestation.
- Sanitation has positive impacts on economic growth and poverty reduction. According to a recent WHO study, every dollar spent on improving sanitation generates an average economic benefit of seven dollars.
- Sanitation with individual household toilets provides relief to women from the chance of chronic constipation and from the vulnerability to violence if they are forced to defecate during nightfall and in secluded areas.
- Sanitation enhances dignity, privacy and safety, especially for women and girls and improves convenience and social status.
- Sanitation in schools enables children, especially girls reaching puberty, to remain in the educational system.
- Improved disposal of human waste protects the quality of drinking water sources.
- Re-use of composted waste for agriculture is an environmental, as well as economic gain
Requirement of Sanitation Programme
Any sanitation programme must satisfy the following Ten Commandments:
- Should not involve human for handling the waste,
- Should not expose the waste to flies, vectors or animals,
- Should not cause odors or unsightly conditions,
- Should not cause surface water contamination,
- Should not cause groundwater contamination,
- Should not cause soil contamination,
- Should not require huge investment to construct,
- Should be simple and inexpensive to operate and maintain,
- Should require small quantity of water for operation
- Should recycle the nutrient in the waste to be utilized in agricultural lands.
Types of Sanitation
Sanitation does not come as a prepared kit, all cutup to ready to process. It comes in a flood of jumbled material that needs to be picked over and sorted out through endless imaginative work. The technologies, approaches and skilled people are readily available. Households, communities, local and national governments, civil society, and private companies all need to work together to evolve appropriate sanitation technology.
There are two types of sanitation
1. On-site sanitation and
2. Off-site sanitation.
- On-site Sanitation contemplates collecting sullage and excreta separately and disposing them within the house site/plot. Sullage after plain sedimentation is used for developing coconut and banana trees and kitchen garden around the house. Excreta, is disposed by adopting certain types of toilets and subsoil dispersion systems.
- Off-site sanitation aims collecting sullage and excreta together as sewage, transporting it to sewage treatment plant for treatment and disposal. Proper planning, installing and operation and maintenance of sewerage system and sewage treatment plant are important requirement. As water scarcity becomes a common issue in many parts of the world, the disadvantages of large scale water carriage or sewerage systems that lead to a consumption of huge quantity of valuable water resources are heighten. Urban areas are consuming up to 50% of the total water demand for hygiene related human activities and toilet flushing. A re-thinking of the water-carriage system to human waste conveyance is necessary especially in places where water resources are scarce. For many low-income communities, particularly in developing countries, off-site sanitation with installation of sewerage system and sewage treatment plant, with its high cost and need for a piped water supply, is not a feasible option. For such communities, on-site sanitation dealing with excrete where they are deposited offers a hygienic and affordable solution.