Introduction
A survey of developing countries by the World Health Organization [WHO] (2012) indicated that 75% of the urban dwellers did not have sewage (that is sewer for excreta disposal) and 25% had no disposal system of any kind in rural areas. 85% lack any adequate sewage disposal facilities and major national and international initiative are clearly required if any substantial improvement in sanitation system in the developing world is to be made next few decades. Turner (2005) state that some area of the world even today are without sanitary method for human sewage disposal, They neither have rural privy system nor city sewage system and that dysentery, hookworm disease and typhoid fever are prevalence in these areas.
Omoregie (2005) states that “while the ability to contact disease depends on the environment of the individual, the cause of constant disease depends on personal habits and ways of living and on how far the rules of nature observed”. The control of sewage disposal is necessary in order to improve and safeguard public health and to protect water contamination.
According to Okun (2009), insanitary disposal of sewage helps to sustain and spread disease. Indiscriminate excretion regularly pollutes drinking water supplies causing sporadic outbreak of disease including cholera, diarrhoea and continual threat of epidemic.
Sewage can be dispose off by the use of;
- drainage septic tank
- seaside
- open space of town
With some of these methods of sewage disposal and good sanitation, the problem of disease and unhealthy environment can be reduced.
Conceptual framework
Sewage disposal constitutes a major problem for communities all over the world. In most cases, poor sewage disposal results into environmental pollution and serious health hazards. However, sewage disposal problems can be reduced to a manageable proportion if adequate sanitary latrines are built. This requires a good planning by the authority concerned.
Mode (2006) stated that the situation of excreta disposal remains a serious problem despite all efforts. Till date, only for a very small fraction of habitants have their sewage disposal.
Akimi (2007) states that Nigeria had not been able to take proper care of sewage disposal problems judging from the poor environment condition in the urban and rural areas and he observed that sewage can easily be handled in areas provided with adequate sewers, but the handling of sewage from built up communities without adequate water and space is not at all easy.
Types of latrines
Unuraye and Olojoba (2005) state the common method of sewage disposal include the following:
- Bucket latrine
- Ventilated improved pit latrine
- Water closet (WC)
- Pit latrine
- Bush attack
- Aqua privy
Bucket latrine
The bucket latrine method is where excreta are deposited into special containers which are placed under platforms. The labourers periodically visit the latrine to empty the content of the bucket with excreta for disposal either by burying or disposition into the lagoon. This is practiced in both the rural and urban communities in developing countries.
The floor and walls should be made of imperious materials which can easily be cleaned with waters. The bucket latrine should be constructed 10ft away from place where food is prepared, consumed or sold. (Unuraye & Olojoba, 2005).
Ventilated improved pit latrine
The ventilated improved pit latrine is a modification of the conventional pit latrine; free from odour, fly nuisance as well as warm gas from the pit latrine. The vent pipe located outside the house makes it possible for the warm gas from the pit outwards (Unuraye & Olojoba, 2005).
Water closet
The septic tank system consist of flushing device known as water closet, the vent pipe, the inspection chamber and the short sewer which leads into the septic tank itself. Another short sewer connects the septic tank to the soaking pit. For the system to function properly, there must be continuous supply of water (Olojoba, 2009).
Pit latrine
The pit latrine is the most common type of sewage disposal/sanitation facility in the rural communities. It consists of the pit, the floor and the house (super structure). The pit is where the excreta are deposited into and allowed to decompose under anaerobic conditions (without oxygen). The pit should be about 15ft deep and 2ft 6 inches in diameter. This depends on the population and duration.
The floor should be reinforced concrete with an orifice (hole) for defecation. This being the strength of the latrine as it will support the superstructure and the pit. The super structure should be well built possibly with corrugated iron sheets or other improvised materials with a well fitted door. It provides privacy and protection to the user (Olojoba, 2009).
Bush attack
This system of bush disposal is mostly common in the rural and some urban centres. This takes place by depositing the excreta into the surface of the soil in the surrounding bush. As it is observed this method violates all the qualities of a sanitary disposal method and should therefore be discouraged. Communities where this method is in practice are pruned to the infestation of hook worm (Ancylostoma) and other worm diseases. Also, diseases like cholera, dysentery, diarrhoea, etc. are common (Unuraye & Olojoba, 2005).
Aqua privy
The aqua privy is made up of a septic tank and a floor, which carried an inlet drop pipe. The lower part of the pipe must be inside the water contained in the tank for at least 10cm from the top. This provides a water seal and prevent offensive odour and fly nuisance. Another pipe lead to the soak away pit which receives the effluent from the aqua privy tank. To avoid exposing the drop pipe, the top water level must be kept constant (Unuraye & Olojoba, 2005).
The provision of latrine in every building in the community
Victor (2007) emphasized that sanitary condition of latrines is an index of civilized educated people, keeping environment clear and sanitary latrines in a hygienic manner can contribute to the longer lives of people. Diocles (2007) expressing on the effect of poor sanitary condition of latrine revealed that the major effect is above bacteria food poisoning and water contamination, resulting to infection of diseases that causes illness. He gave reasons for poor sanitary condition of latrines as;
- Due to ignorance
- Lack of finance
- Role of belief and customs
According to Famous (2008) the crusade of environmental sanitations and the problem of good sanitary condition of latrine, clean, healthy and beautiful environment have become so great that Delta State government had to set up a task force to tackle it. Godwin (2009) stated that 85% of the people in the state have sanitary latrine but they do not make good use of them while 15% of them do not have sanitary latrine.
Oluwande (2008) stated that pit latrine is the cheapest sanitary method of sewage disposal in rural area where sewage consists mainly of excreta and the important considerations for its provision are siting, construction and maintenance. He also said that the floor part is the most important aspect that will encourage or discourage people from using the pit latrine and aqua privy has great potential in the homes of people who dislike latrine but cannot operate on water system either because of lack of money or their house are not connected to a pipe borne water supply.
Standard condition of latrine
The best and convenient types of sanitary latrine currently used are the water system (David, 2012). Rastalaid (2008) comparing unconventional improved pit latrine with ventilated improved pit latrine based on the disadvantages associated with improved latrine highlighted that there are so many risks involved in using pit latrine. Based on this he expressed the following points:
- The risk involved during digging.
- The risk of falling into pit when log or plank used in crossing the pit got rotten and broken.
- The tendency of discharging faeces on the floor of the latrine.
- The offensive odour because of nearness to house.
The ventilated pit latrine is free from all these disadvantages with exception that most rural area dwellers do not have sufficient money to adapt to this method. Lucas and Gilles (2007) maintained that ventilated improved pit latrines (V.I.P) or ventilated improve double pit latrine (V.I.D.P.L) are low-cost, hygienic, widely accepted. The ventilated improved pit latrine has been designed with the following five principles:
- Durability
- Ventilated and insect control
- Improved safety
- Improved maintenance
- Construction method
The ventilated improved pit latrine has been adapted and improved to meet the more complex conditions or urban communities in the rural areas, when pits are filled, they are covered permanently and the superstructure is relocated.
Sanitary condition of latrine
Turner (2007) commenting on sanitary condition observed that “some areas of the world even today are without sanitary condition of latrine. They have neither rural privy system nor city sewage system. The observation holds for most rural and even urban areas in Nigeria. He went further, to say that dysentery, hookworm disease, diarrhoea, cholera and typhoid fever are prevalence in these area or often sweep across areas that have poor sanitary and environmental conditions and the above demand adequate sanitary conditions of latrine for effective control.
Omoregie (2005) also noted that “the ability to control diseases depends on the environmental condition of the individual, personal habits and hygiene. Victor (2007) emphasize that proper maintenance of latrine in good sanitary condition is an index of civilized and educated group of people keeping environment clean and good sanitary sewage disposal in hygienic manner can contribute to longer duration of the people’s lives.
Public health implications of insanitary condition of latrines
Oluwande (2008) stated that greater part of the population of the tropical lives in rural area where living condition are extremely primitive, mainly the under developed areas. Hundreds of people may be crowded into a small village which has neither or proper water supply nor any latrines and the surroundings of houses are littered with indiscriminate defecation and this conditions leads to infectious diseases.
Unuraye and Olojoba (2005) stated that indiscriminate excretion regularly pollutes drinking water supply causing sporadic outbreaks of diseases including cholera and diarrhoea infections and there is continual threat of epidemics of ascariasis, trichuriasis, etc.
References
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Akimi, S. O. (2007). The present sanitary conditions, a focus on poor sewage Disposal method and the associated with hazards (unpublished).
David, O. (2012): Domestic and industrial waste water management, written material (unpublished).
Diocles, U. I. (2007). Waste management and control report to the federal council for science aid technology. Washington.
Duncan, D. (2005). Health aspect of excreta and Waste management sewage disposal. New York: John Wiley and Sons.
Famous, D. (2008). The need for regular environmental sanitation, written material (unpublished).
Godwin, M. (2009): Developing countries sanitation. A report for IDRC of Canada. Canada: IDRC Ottawa
Lucas, A. O. & Giles, H. M. (2007): A short textbook for preventive medicine for the tropics (4th ed.), London: Hodden and Stoughten.
Mode, D. (2006). The present sanitary condition. A paper presented to the federal health department.
Olojoba, A. O. (2009). Millennium technology in waste management and environmental pollution mitigation. (1st ed.) Ughelli: Ama Ohoror Press.
Omoregie, N. (2005, April 11). Hazards of poor refuse and sewage disposal. The Sun. Vol. 56, p.8.
Oluwande, P. A. (2008). Experimental investigations of some factors affecting the strength and cost of pit latrine concrete floor slab. Ibadan: University Press
Turner, C. E. (2005). School health and health education. Ibadan: Mosby Press.
Unuraye, L. O. & Olojoba, A. O. (2005). Fundamentals of industrial and environmental health management (2nd ed.), Ughelli: Ama Ohoror, Press.
Victor, T. (2007): Refuse and sewage disposal methods written material (unpublished).