Introduction

Nigeria as a country could be said to be urbanizing at an astonishing rate. The share of Nigeria’s urban population was revealed to have increased from 20 percent in 1970 to about 38 percent in 1990, with over 40 million out of the nearly 110 million living in the cities and towns. Lagos being one of the major cities in Nigeria cannot but said to take a lion share out of this 40 million urban dwellers.  This seeming envious position has serious implications for the provision of urban services such as water, sanitation, road and waste disposal. The ability or inability of the inhabitant to address the multiplicity of problems that usually accompany the largest unmet demands are aggravated by the occurrence of their environmental problems. These include air pollution, water pollution, noise pollution and waste disposal problem, which unfortunately is the most serious environmental problem in Lagos state.

Concept of Waste and Types

Lawal (1995) define waste as any substance, solid, liquid or gaseous that remains as residue or an incidental by-product of the processing of a substance or for which no use can be found by the organism or system that produces it. Simply defined, Okebukola (1996) sees waste as a material that is no longer needed and therefore, discarded.

Aminu-Kano & Lawal (2001) however emphasis that waste could be photodegradable, e.g. (broken down by sunlight after a time, e.g. plastic) or non-bio-degradable, e.g. steel, biodegradable (broken down by bacteria on exposure, e.g. organic matter) Examples are household waste, industrial (which often contain toxic chemicals), medical waste (which may contain organism that cause disease), and nuclear waste (which is radioactive). Every human activity generate waste but is the accumulation of  wastes that constitute environmental health hazards. Osinowo (2001) observes that waste generation occurs through domestic, commercial, industrial, agricultural and other social activities. Domestically, human activities  such as environmental sanitation, food preparation, consumption of packaged foods, laundry, washing of utensils, discharge of unwanted household items or unserviceable household equipment and old furnishing all lead to huge volume of waste. Activities like retailing and distributive trade, small, medium and large scale industrial operations also bring about the generation of both solid and liquid waste. On-farm operation and in-farm gate activities are usually characterized by waste generation. typical examples include timber and wood-processing industry which generate large quantities of waste in form of sawdust and shavings.

Ali (1995) gave the composition of the various wastes that are generated in Nigeria as follows:

§  Household waste – 85%

§  Commercial waste - 8%

§  Swage Sludge – 3.5%

§  Industrial Waste – 1.6%

§  Agricultural waste – 1.1%

§  Mini waste – 0.5%

§  Hazardous waste – 0.3%

§  Radioactive waste – 0.02%

Majority of these wastes are quite hazardous. As a result of their chemical, physical and biological characteristics, they confer both long and short  term effects on human beings and  the environment, hence, the need to think about their proper management. For example, sewage or faeces is the most hazardous waste generated daily by human. It contains high concentration of pathogens like virus, bacteria, protozoa and helminthes (worms). Olaniran (1995), while quoting Feachem et al. (1983) observed that one gram of human faeces may contain 10 infectious virus particles, regardless of whether the individual is experiencing any discernible illness. The ingestion of this may result in epidemics of cholera, typhoid fever, amoebic and bacillary desenteries, roundworm and hookworm infections, infectious hepatitis and schistosomiasis.

Peculiar Type of Waste in Lagos Metropolis

The high population growth rate and rapid/uncontrolled urbanization, which Lagos is experiencing, make the generation of some particular kinds of waste in large volumes highly unavoidable. For instance, in 1994 alone, the tonnage of refuse collected by Lagos State Waste Management Authority (LAWMA) was as much as 185,417 tonnes of waste (Alo, 2001).

 The summary of the most common ones are presented in the table below:

 Past and Current Efforts at Addressing the Problem of Waste Disposal and Management in Lagos

Effective appraisal of the past and current efforts at addressing the problems of waste in the Lagos metropolis demands a proper understanding of what waste management itself means. Waste Management as described by Lawal (1995) as the appropriate method of disposing waste safely in such a way that makes it less harmful. It involves appropriate disposal of sewage and household refuse. It could come in form of waste treatment or energy conservation. The latter requires the recycling of the nutrients and useful materials contained in domestic or industrial waste. On the other hand, waste treatment can come in different forms. That is, as primary treatment which allows screens to be used to filter out large debris through a sedimentation tank for the suspended solids to settle as sludge, or as secondary treatment, that uses a biological process to break down waste? There is also the tertiary treatment that requires series of specialized chemical and physical processes to reduce the quantity of one or more of the pollutants remaining after primary and secondary treatments through precipitation, absorption and electro-dialysis or reverse osmosis.

Attempt at combating waste disposal problem in Lagos metropolis is not a recent development. Ever since the days of sanitary health inspect inspectors (Wole Wole) when the ‘pail system’ Agbe po with the cognomen: (Ode ori kereni somi dagbo; o se omo eja lo ore) – he who pollutes the lagoon from the top of the bridge and bless the fish) of disposing human waste was the order of the day, conscious efforts has been geared towards the issue of waste in the metropolis. Successive government had adopted various strategies of waste management as far back as 1986. Akpan (2001) observed that in 1986, the lagos State government undertook Lagos the Lagos Solid waste and Storm Drainage Project with finances from the world bank. The total cost of the project was $ 164 million out of which 68% was for solid waste, the responsibility of which was given to the state agency for waste management. Between the period and 1991, solid waste management in Lagos improved, but by 1991, the impact declined following the deteriorating state of the facilities and equipment being for  carrying this enormous task. This equipment became unserviceable due to the insufficient funding needed for repairing or replacing.

This state of affairs in the business of managing waste ignited the commercialization policy and the subsequent decentralization of waste disposal and management in the state between 1991 and 1996 as well as the return to centralization in 1997. specifically however, the past and current effort at managing waste in Lagos can be further discussed under the following subheadings: