Urbanization and Housing for Low-Income Earners in Nigeria: A Review of Features, Challenges and Prospects

This review paper examines urbanization and housing for low-income Nigerians. The aim is to provide a better understanding of the ways in which urbanization has progressed and impacted negatively on housing for the low-income urban residents, and the possible strategies for ameliorating this situation in Nigeria. Drawing on a systematic review of published literature, the paper reveals that urbanization in Nigeria has manifested in rapid population increase, transformation of erstwhile rural to urban settlements and emergence of primate cities. It identified the main drivers of urbanization in Nigeria to include natural population increase, economic and religious activities, state policies on reclassification of settlements and decentralization of governance structure. The study also found that urbanization has exacerbated housing challenges among low-income earners by promoting the proliferation of urban slums and poverty; and that these challenges have persisted and are escalating unabated due to the emphasis on top-down approach to social housing and the lack of understanding of the specific housing delivery strategies that can be engaged in resolving these challenges in Nigeria. The paper concludes that since urbanization will intensify in years to come, there is the need for a change of approach by engaging in strategies that promote participatory and assisted self-help housing among low-income people to prevent the current situation from degenerating further.


Introduction 1.
Urbanization is perhaps one of the oldest global phenomena that are currently shaping the way we live, play and work.Whereas the rate of urbanization appears to have slowed down in the developed countries, its impacts on less developed countries have been very dramatic as these countries are ill-equipped to take full advantage of its benefits and manage the adverse consequences.In Africa, South America and Asia, rapid urbanization has come with complex management challenges in housing, transportation, land use, environmental degradation, crime, unemployment and public service delivery.These challenges appear to be overwhelming and very difficult to eradicate or control.
Although housing is a necessity of life, rapid urbanization has made access to decent housing to be elusive to many low-income earners in most Nigerian cities (Aribigbola, 2008).This is because the demand for housing and basic services has outstripped its supply in this country (UN-HABITAT, 2010).Nigeria, Africa's largest economy, has one of the highest rates of urbanization put at around 5.8 percent (National Economic Empowerment and Development Strategy (NEEDS), 2004).It is among the countries with the worst urban housing situations in the world ( UN-HABITAT, 2006).This challenge is particularly very critical among the urban poor and low-income earners (Mbamali and Okoli, 2002) who constitute about 80 percent of Nigeria's estimated 60 million urban residents (Aluko and Amidu, 2006).
Urban housing crisis in Nigeria have manifested in homelessness and poor living conditions.Thus, governments in this country are confronted with two main challenges.First, is how to improve the housing situation of people living in urban slums; and second is how to assist low-income earners to gain access to decent housing at affordable cost (Ibem, 2011).In the face of these challenges, governments in Nigeria have since the 1920s engaged in mass housing delivery with the aim of meeting the housing needs of a majority of the citizens (Awotona, 1987;Ikejiofor, 1999;Ademiluyi, 2010).However, studies have shown that previous public housing schemes have not made any appreciable impact in resolving urban housing challenges in this country (Akinmoladun and Oluwoye, 2007;Ibem et al., 2011) and the search for sustainable solutions to the housing crisis continues.
There is a consensus in the literature that rapid urbanization has contributed significantly to exacerbating urban housing challenges confronting low-income people in many developing countries, including Nigeria.However, there is a gap in knowledge on the specific housing strategies or approaches that can help to solve the intricate housing challenge in Nigeria.It was in a bid to narrow this gap that this paper sets out to examine urbanization and housing for low-income urban residents in Nigeria.The objectives are to: i.
Examine the features of urbanisation in the pre-colonial, colonial and post-independence era ; ii.
Review the various strategies engaged in by the government in addressing urbanization-related housing challenges; and iii.
Identify the way forward for housing low-income earners in Nigerian cities.This review paper contributes to knowledge in providing a fresh insight into the nature of the urban housing challenges confronting low-income earners as well as the previous and current strategies adopted by governments in addressing these challenges.It also contributes to knowledge by identifying future directions for addressing the housing needs of low-income earners in a rapidly urbanizing Nigeria.

2.
As noted earlier, the aim of this paper is to examine the features of urbanization and how these have impacted negatively on housing for low-income urban residents in Nigeria.In order to achieve this goal, a systematic review of research literature was considered appropriate for this study.The is principally because of the nature of the objectives of the study; and the fact that the existing studies (Green, 2005;Whittemore and Gray, 2005) have shown that systematic review is an important scientific research tool that can be used to synthesize and present the result and implications of large quantity of research publications on a subject to inform research and practice.Therefore, in gathering data used in this paper, a five-step process of (i) framing of research questions/objectives (ii) identifying relevant studies (iii) assessing the quality of studies (iv) summarizing the evidence; and (v) interpreting the findings as suggested by Khnan et al. (2003) and Green (2005) was adopted.
In adopting this research approach, extensive search and review of peer-reviewed journal articles, conference papers and books were conducted between February and September 2015 using Scopus online database as the main source of literature.Scopus was chosen because according to Falagas et al. (2008), it is one of the largest online databases covering a wider range of journals, with special features in keyword searching and citation analysis.In addition, a search was conducted in Google Scholar to identify other relevant journal articles that may not have been captured in Scopus.Our search algorithms were a combination of text words such as 'Urbanization in Nigeria' which yielded 364 items, 'Low-income housing in Nigeria' which produced 45 articles and 'Challenges of low-income housing in Nigeria' which also produced only six articles.Both journal articles and conference papers were included in the searches because they are considered veritable sources of published research data.
The searchers in the two databases produced 415 articles.Both the titles and abstracts of all the articles were first reviewed by the authors to identify those for which full texts should be reviewed and included in the research.The initial review process resulted in the selection of 194 articles considered potentially relevant to the subject matter.The selection of the actual articles reviewed was based on their degree of relevance to the research objectives.The rating system adopted in the selection of the articles was "1" for low relevance, "2" for medium relevance and "3" for high relevance.Based on this, only articles rated "3" by the authors were selected and subsequently included in this study.The total number of articles reviewed is presented in the reference section of this paper.Each article selected was carefully reviewed by the authors to identify information and data relevant to the study.
Data derived from the systematic review of literature were subjected to content analysis.This involved thematic coding of the issues; identification of the features of urbanization and housing development; and the challenges associated with these in Nigeria as reported in the articles reviewed.Findings are presented in the next section of this paper.

Features of Urbanization in Nigeria
In view of the unique geo-political antecedents of Nigeria, it is important to discuss the trends and features of urbanization based on the different dispensations that have evolved and helped to define the geographical and political entity called Nigeria.To this end, attempt was made here to classify the process and features of urbanization in Nigeria into three broad political dispensations: pre-colonial, colonial and post-independence era.

Urbanization in the Pre-Colonial Era
Although information on pre-colonial urbanization in Nigeria is scanty, Clark (1998) observed that urban civilization existed in ancient Egypt, India, China, Cambodia, Peru, Mexico and Nigeria as far back as the time of the industrial revolution in the west.In fact, Mabogunje (1969) noted that urbanization in Nigeria started in the medieval era, especially in north due to the growth and decay of the Sudanese empires that existed in Ghana in 800 A.D., in Mali about 1500 A.D and later on, Songhai in the seventeenth century.He further explained that the emergence of urban areas in the northern part of Nigeria was also linked to the military Jihad led by Uthman dan Fodio (Mabogunje, 1969).Okpoko (1998) also remarked that the expedition of the Hausa Kingdoms and Kanem-Bornu Empire was instrumental to the emergence of traditional cities such as Kano, Zaria and Katsina among others.
In the southwestern part of Nigeria where the Yoruba speaking people reside, traditional towns such as Ketu, Owo, Sabe, Benin and Oyo existed in the pre-colonial era.From these towns emerged powerful kingdoms such as Oyo, Ekiti, Benin and Ondo, among others (Okpoko, 1998).By the mid 19 th century, six out of the thirty-six towns in the southwestern, Nigeria, had populations of more than 40,000 people each.Mabogunje (1969) and Oyeleye (2001) agree that the growth and development of Yoruba towns can be traced back to the eighteenth century, and that Yoruba towns grew as administrative centers.Atanda (1980) added that the growth of Yoruba towns was propelled by agriculture, iron mining, smelting and clothing as well as the existence of coastal environment and waterfront, which facilitated the free movement of people and goods through the waterways.In addition, the series of intra-Yoruba wars towards the end of 18 th and the beginning of 19 th centuries, which led to the dispersal of Yoruba people also contributed to the emergence of numerous urban centers in Southwest Nigeria today (Oyeleye, 2001).For example, Ibadan, the largest of all Yoruba settlements, is believed to have been established in 1829 as a war camp for warriors coming from Oyo, Ife and Ijebu areas of Yoruba land (Oyeleye, 2001).
Pre-colonial urbanization was also found among the Igbo speaking people of Southeast Nigeria.Notable was the ancient Igbo-Ukwu civilization in the present day Anambra State, which is among the oldest in Nigeria.According to Okpoko (1998:41), 'village-group states developed in Igbo speaking area in the seventeenth century as a result of initial contacts with the neighbouring Igbo and non-Igbo groups and the trans-Atlantic trade'.He identified Nri and Arochukwu as having considerable populations in the thirteenth and seventeenth centuries, respectively, and concluded that, like their Yoruba counterparts, these towns grew as administrative centres.
It is evident from the preceding paragraphs that the first evidence of pre-colonial urbanization in Nigeria was in the savanna region of northern Nigeria, which had early contacts with the Arabs due to the trans-Saharan trade, before the forest zone in the south, where the Yoruba, Igbo and other ethnic groups reside.By the middle of 19 th century, the southwestern and northern parts of Nigeria were the major areas of urban development (Oyeleye, 2001) and as at 1890; there were 25 urban centres in Nigeria (Ayedun et al., 2011).The implication of this is that pre-colonial urbanization in Nigeria was due to religious, trade and commercial activities and political factors as explained by Andah (1988).

Urbanization in the Colonial Era
Colonial rule got underway in Nigeria in 1861 when Lagos was ceded to the British.However, Nigeria formally became a political entity in 1914 through the amalgamation of the erstwhile Northern and Southern protectorates.The account by Oyeleye (2001) reveals that the presence of the British manifested in Nigeria initially through missionary activities and thereafter through the Royal Niger Company.Consequently, urbanization in colonial Nigeria began with the establishment of colonial towns such as Lagos, Kaduna, Port Harcourt and Nsukka for administrative purposes.This was followed by the designation of Jos and Enugu as industrial towns for the mining of tin and coal, respectively.The construction of the first rail line in 1895 linking Lagos and Kano in 1912 and the second one in 1913 linking Port Harcourt with Aba, Enugu, Jos, Kafanchan and reaching Kaduna in 1923,on the one hand encouraged speedy evacuation of raw materials from the centres of production to the ports for export to British and European industries.On the other hand, it facilitated the emergence of new towns, which encouraged the movement of people from the hinterland to the towns linked by the rail lines.These towns latter became centres of commerce and administration and diffusion of western culture.
Historical fact shows that in 1921 when Nigeria's total population was about 18.631 million, at least 1.345 million lived in cities which had population of over 20,000 people.By 1952, when the first official census took place, about 10.6 percent of the total population of 30.403 million were urban dwellers (Oyeleye, 2001).Mabogunje (1969) linked colonial urbanization in Nigeria to factors, ranging from political stability, the urban economic functions, regional factor, and demographic factor to the minority factor.However, Oyeleye (2001) remarked that colonial urbanization in Nigeria was as a result of the introduction of monetized economy based on agriculture, exploitation of mineral resources and the development of modern transportation system by the British.
In all, it can seen from this review that colonial urbanization in Nigeria was due to the creation of new colonial cities, the introduction of planned and low density residential quarters called Government Reservation Areas (GRAs) in Nigerian towns and the construction of south-north rail lines.Unlike the pre-colonial era when most urban areas were in the northern part of Nigeria, the reverse was the case during the colonial era as most of cities in Nigeria were found in the southern region.The initial contacts with western civilization that came with colonial rule at the onset of twentieth century might help to explain this development.

Urbanization in the Post-Independence Era
The UN-HABITAT ( 2010) report shows that in October 1960 when Nigeria gained political independence from the British, 133 settlements had populations of over 10,000 people.This figure rose to 253 in 1980 and 450 in 2000.The 1963 national census also reveals that there were 24 cities with a population of over 100,000; 55 with over 50,000, and 183 with over 20,000 people in Nigeria.Of the 183 cities with populations of 20,000 people and above, 70 were located in the northern Nigeria, 78 in the west, 29 in the east and 6 in the mid-western region.In 1990, there were 21 State capitals in Nigeria, each estimated to have more than 100,000 inhabitants.The 1991 population census indicated that about 359 settlements had at least 20,000 inhabitants, and that the southwest was the most urbanized part of the country, while the middle belt was the least.Further, the UK Department for International Development (DFID, 2004) report on Urban and Rural Development in Nigeria indicates that 18 cities had a population of more than 500,000 people in 2002, while current estimate suggests that by 2020 the number of urban areas with populations of over 10,000 in Nigeria will be 574.Presently, going by the definition of urban centre in Nigeria as a settlement with up to 20,000 residents (Okeke, 2004) and the fact that every local government headquarters is classified as an urban centre, it can be concluded that there are over 774 urban areas in Nigeria, which is the highest in sub-Saharan Africa.
Besides the increase in the number of urban areas, which has been dramatic, an interesting scenario is also seen in the percentage of the total population who are urban dwellers in Nigeria.Table 1 shows the percent of urban residents in Nigeria before and after independence., 2010).This implies that the number of megacities is likely to increase with the majority of settlements in Nigeria classified as urban areas in the next 34 years or so.
Regarding the factors that have contributed significantly to making Nigeria an increasingly urbanized society since political independence, Taylor (1988) noted that government's deliberate policy on decentralization of administrative structure through the creation of States and Local Government Areas, and the establishment of four main industrial-urban conurbations: Lagos-Ibadan; Kano-Kaduna-Zaria-Jos; the Benin-Sapele-Warri and Port Harcourt-Aba-Onitsha-Enugu are major factors.It is also believed that the prosperity of the oil boom era (the 1970s) which provided funds for major urban infrastructural development across the country was instrumental to increasing the tempo in rural-urban migration, which among other things encouraged the concentration of population in urban areas.This ultimately led to the emergence of primate cities like Lagos, Kano and Port Harcourt, and other major cities across the 36 States in Nigeria.It can be inferred from the foregoing that natural population increase, economic and state policies on reclassification of settlements and decentralization of governance structure are the main drivers of urbanization before, during and after colonial rule in Nigeria.

Urbanization and the Housing Challenge among Low-income Earners in Nigeria
There is a consensus in the literature that rapid urbanization has contributed to persistent housing challenges among lowincome urban residents in Nigeria in several ways.First, there is the proliferation of urban slums in core areas and periphery of Nigerian cities.This is principally due to the unplanned nature of most Nigerian cities and the inability of the formal housing market to meet the demand for housing by low-income earners.From the work of Ogbazi (1992) it is known that pre-colonial cities in Nigeria developed and grew without any formal urban planning as land use and their spatial structure were based on native laws, customs, traditions and cultural beliefs of the people as well as the dictates of traditional rulers.This means that there were little or no plans put in place to deal with issues of urban planning and housing provision for the people from the onset as explained by Mayaki (2003).The consequence of this is seen in the spatial structure and physical conditions of most Nigerian cities today, particularly in the core areas.As the ancestral homes of the indigenes, the urban poor and low-income people, Okeke (2004) and Dimuna and Omatsone (2010) described the core areas of Nigerian cities as the most congested with poorly designed and constructed houses clustered together and arranged in a disorderly manner with inadequate provision of basic social infrastructural facilities such as refuse disposal facilities and pipe-borne water.Put succinctly, the core areas of Nigerian cities are synonymous with slums of poor and unhygienic living conditions.
Second, rapid urbanization has accelerated the process of uncontrolled expansion of urban areas beyond their physical limits in a process known as sprawling.As already noted, during the colonial era, little or no attempt was made at improving the poor urban planning and housing conditions in traditional cities, rather selective urban planning and housing schemes in the GRAs were deliberately introduced by the British.This resulted in urban spatial structure of massive unplanned ancestral (core) areas and sparsely planned European quarters in many Nigerian cities.After independence, came the oil boom era, which ushered in rapid urban growth and increasing pressure on the existing urban infrastructure and housing.Consequently, the supply of housing and basic amenities was not in tandem with the rate of urban population growth leading to congestions and rapid deterioration of the core areas of cities.In a desperate move to meet their housing needs, individuals and households began to turn to urban fringes, leading to the evolution of unplanned residential developments characterized by sub-standard houses without adequate access to basic social amenities, which later became the order of the day as explained by Olujimi (2009).Indeed, Nigerian cities have in the last ten decades evolved spatial structure of unplanned core areas, planned residential neighbourhoods (public and private housing estates) and unplanned peri-urban residential neighbourhoods.Areola (2001) was of the view that this spatial structure has contributed to the difficulties experienced in the several attempts at improving the living conditions of residents of the core areas and fringes of Nigerian cities.It is therefore not surprising that although the proportion of urban population living in slums declined between 1990 and 2010, more than three-fifths of the total urban population in Nigeria still live in housing conditions described as slums as shown in Source: UN-HABITAT (2010) Lastly, the consistent decline in economic growth and development in the face of rapid urbanization has resulted in a sharp increase in the number of poor people living in urban areas in Nigeria.There is no gain saying that Nigerian cities have continued to grow both spatially and demographically under conditions of economic stagnation and underdevelopment, which have led to high rate of unemployment and urban poverty.Although, the United Nations Population Fund (2011) report reveals that around 64 percent of Nigerians live in poverty, Figure 1 shows that urban poverty increased from 17.2 percent in 1980 to 58.2 percent in 1996, but declined to 43.2 percent in 2004 in Nigeria.One of the principal factors responsible for this development is the high rate of rural-urban migration, which has been heightened by the sharp disparities between urban and rural areas in terms of access to job opportunities, basic amenities and services.As the rural areas have become increasingly marginalized in national development programmes, many young people in Nigeria have abandoned agricultural production in search for white-collar jobs in non-agricultural sectors.Since the available job opportunities in urban areas are not enough to go round, many immigrants are trapped in the net of unemployment, while those employed are poorly remunerated.Among other things, this has contributed a large proportion of low-income earners in urban slums who are unable to gain access to decent housing at affordable cost in Nigeria resulting in homelessness, especially among children and youths (Edewor, 2014).

Government's Efforts at Resolving Urban Housing Challenges in Nigeria
Okpoko (1998) has noted that the characteristics, processes, manifestations and impacts of urbanization may differ from place to place depending on the environmental, socio-cultural and political situations of a society.The existing studies (Fadamiro and Fadairo, 2000;Cohen, 2006) however show that rapid urbanization exacerbates urban poverty, violence, insecurity, homelessness, poor access to basic sanitation and services, environmental degradation and constitutes a threat to sustainable development in many developing countries.As would be expected, successive governments in Nigeria have since the mid 1920s engaged in different strategies in a desperate attempt to resolve urban housing challenges confronting low-income earners.In this section, we examine some of these key strategies, their outcomes and implications for housing low-income earners in Nigeria.

Slum Clearance and Resettlement Strategy
The first attempt by government to improve the housing situation of the Nigerians was the slum clearance and resettlement exercise, which took place in Lagos in the late 1920s.This was in response to the outbreak of the bubonic plague in Lagos and the now defunct Lagos Executive Development Board (LEDB) cleared the affected areas with the construction of new houses which were sold to the public (Olotuah and Falaye, 2000).In 1955, another slum clearance exercise was also carried out in Lagos by the same LEDB.George (2006) observed that some 200,000 people were displaced in that scheme and that the inability of government to successfully relocate them exposed the socio-economic problems associated with slum clearance in Nigeria.We also found from the literature that between 1962 and 2010 several slum clearance exercises and resettlement programmes involving remodelling, re-planning, upgrading parts of old traditional cities have been carried out across Nigeria (see Sule, 1990;Agbola and Jinadu, 1997;Babarinde and Adesanya, 2010;Dimuna and Omatsone, 2010).Despite the good intentions of government to improve the living conditions of residents in urban slums in Nigeria through these programmes, the UN-HABITAT ( 2006) indicated that slum clearance programmes in Nigeria have suffered from inadequate funding and a lack of suitable land to relocate displaced persons in Nigeria.It was on this premise that Agbola and Jinadu (1997) and Umeh (2004) argued that this strategy had failed to provide low-income residents with decent and affordable housing.

Sites-and-Services Strategy (SSS)
Another strategy adopted by government in addressing shortage of urban housing in Nigeria is the sites-and-services scheme (SSS).This strategy is based on the idea of assisted self-help housing pioneered by John Turner.Aribigbola and Ayeniyo (2012) noted that SSS are designed to enable the poor and low-income people gain access to housing by encouraging them to construct their homes over a period of time.In the SSS, government and international development agencies usually provide serviced plots for individuals to erect their own houses.SSS were first introduced in Nigeria in the mid-1970s in the then newly created states of Bauchi, Benue, Gongola, Imo, Niger, Ogun and Ondo as well as in Lagos.It involved the Federal and State governments and the World Bank.The governments provided land, administrative support and counterpart funding and about 24,397 serviced plots were made available in the aforementioned States (UN- HABITAT, 2006).Due to funding challenges, the scheme could not be extended to other States, but between 1984 and 1986, the scheme was resuscitated in Lagos, Kano, Imo, Kwara, Ondo, and Rivers States and the Federal Capital Territory, Abuja.The Federal Ministry of Works and Housing and the Federal Housing Authority (FHA) provided serviced plots and basic infrastructure (e.g.roads, water and electricity) on the plots.Ajanlekoko (2001) noted that between 1984 and 1991 about 85 million naira (US $21.25 million) was expended in the provision of 20,000 serviced plots in 20 States of the federation.Also, in 1999, the Federal Government of Nigeria awarded contracts for SSS involving 7,730 plots in parts of the country.Ibem et al. (2013) however observed that there were no records that many of the sites were made available for the people to build their houses.
Under the Public-Private-Partnership (PPP) strategy to public housing, the SSS was reintroduced as a mortgagebased housing scheme.In the PPP strategy, the government provides land, while private sector partner sub-divide and provide basic services to the site.Ibem (2011) observed that 2,000 serviced plots at an average cost of between N0.5 million (US$3,333) for low-and middle-income people and N 1.5 million (US$10,000) per plot for the high-income people, were provided in Ikorodu, Lagos State.Although high cost and the modalities for allocating serviced plots, which were lopsided in favour of government officials, politicians and their associates contributed to the failure of previous SSS, the introduction of mortgage acquisition in the SSS under the PPP arrangement is a step in the right direction in ensuring that such schemes are affordable to low-income earners in Nigeria.

The Core Housing Strategy
Closely related to the SSS is the core housing strategy (CHS).This is also called incremental housing and has globally been acknowledged as one of the most viable ways of providing housing for the low-income people in the developing countries.In view of this, the Nigerian government has incorporated the CHS into the SSS with the Federal Housing Authority (FHA) constructing core housing units on some of the plots provided in the National SSS of 1986 (Ajanlekoko, 2001).A recent survey by Ibem (2012) also revealed that the CHS succeeded in housing low-income public sector workers in Abeokuta, Ogun State, south-west Nigeria.The strategy worked in this State because core housing units were constructed by the government using direct labour and allocated to beneficiaries on mortgage basis at a cost less than N1 million (US$6,667) with flexible repayment period of between 15years and 25years.Although, the scheme was funded with credit facilities from the Federal Mortgage Bank of Nigeria (FMBN) under the National Housing Fund (NHF), of the 1,000 housing units planned for construction, only 270 housing units, representing 27percent were actually constructed as at 2010.Notably, that scheme was targeted mainly at public sector workers, who constitute a very small proportion of low-income urban residents in the State; hence, there is a need to extend similar scheme to low-income earners in the informal sector of the economy.

Direct Construction of Housing Units
Direct construction of housing units by government appears to be the most controversial of all the strategies so far adopted in resolving urban housing crisis in Nigeria.Under this strategy, government agencies are engaged in the direct construction of housing units, which are either rented or sold to the public below market prices.Beginning with the colonial era, government's involvement in direct construction of housing units in the GRAs and African Quarters for expatriate and senior indigenous staff, respectively, was through the now defunct Public Works Department (PWD).The establishment of housing corporations by the defunct regional governments in 1958 was an attempt by the government to provide housing for the people.Onibokun (1985) however explained that due to the lack of funding and requisite manpower, many Nigerians did not benefit from the activities of the regional housing corporations.
Between 1975 and 2010, a number of social housing programmes involving direct construction of housing by the government were initiated by both the Federal Military and Civilian Governments in Nigeria.Some of these housing programmes included the National Low-Cost Housing Scheme (1975-1980), Shagari's Low-Cost Housing Programme (1980-1985), the National Housing Programme (1994)(1995), the National Prototype Housing Programme (2000)(2001)(2002)(2003), the Presidential Housing Mandate Scheme (PMHS) (2004)(2005)(2006) and PPP housing schemes.Although there are conflicting figures on the actual number of housing units completed in each of these programmes, Table 3 shows that between 1962 and 2010 a total of 653,271 housing units were expected to be constructed in the different housing schemes across the country.However, only 95,594 housing units were actually constructed (the figure on the number of housing units constructed in the 2000-2003 period is not available, and thus excluded from the data in Table 3. Source: Compiled from various sources, including Onibokun (1985); UN-HABITAT (2006) Ibem et al. (2011) It is obvious from the foregoing that none of the previous public housing programmes achieved up to 50 percent of targeted number of housing units.Apart from the period between 2006 and 2010 in which there was 43 percent achievement, in other periods, the achievement levels were far less.Thus, the impact of these programmes in addressing the existing housing problems among low-income earners in the country can best be described as minimal.

Why previous Social Housing Schemes failed in Nigeria
Several attempts have been made by scholars to advance reasons why the previous state sponsored housing schemes in Nigeria failed to provide the desired results.Most of the reasons have to do with the lack of adequate funding, corruption in the implementation and allocation of complete housing units, political interference and the lack of adequate monitoring and evaluation of the programmes (Ibem et al., 2011).For example, Ibem, Opoko and Aduwo (2013) investigated the outcomes of the PMHS initiated by the Obasonjo's administration to provide 18,000 low-cost housing units between 2004 and 2006 using local building materials and found that the scheme was implemented in very few States in the country with very small number of housing units provided.The challenges of that scheme were related to poor design and implementation strategies, inadequate funding and low organizational capacity of the three public agencies: National Building and Road Research Institute (NIBRRI), Association of Housing Corporations of Nigeria (AHCN) and the FMBN charged with the responsibility of implement that scheme.Government sponsored mass housing schemes are supposed to be based on a three-tier institutional framework, involving Federal, State and Local Government as outlined in the National Housing Policy in 1991 and 2012.However, while the FHA, Federal Ministry of Land and Housing and the various State Housing Corporations have been actively involved in the previous schemes, the third tier of government-the LGAs and community-based organizations such as housing co-operative societies that are supposed to represent the interest of the grassroots people, have not been actively involved in such schemes.We argue that the lack of participation of local urban authorities and nongovernmental organizations in such schemes accounted for the massive failure of those programmes in making any reasonable impact on the housing conditions of low-income people in Nigeria.This implies that the housing programmes targeted at low-income citizens were, from the onset, doomed to fail due to dysfunctional institutional framework.
There is also the issue of lack of adequate data on the exact number of low-income households who really need housing in Nigeria.Poor data capturing on the rate of urban population growth has been the bane of planning and programming in Nigeria.Although, a number of population censuses have been conducted in Nigeria, the results in many cases are still being contested.Thus, there are no accurate and reliable data on the number of low-income households in urban areas for which provision is to be made.Without accurate data, it is difficult to generate effective plans and programmes that would have tangible impacts on the life of the people.This has been one of the principal challenges in the design of targeted housing programmes for the low-income people in Nigerian cities; and thus partly accounts for the failure of most public housing programmmes in this country.
Housing for Low-income Earners in Nigeria: The Way Forward 4.
Going by the magnitude and dimensions of urban housing crisis and performance of the different strategies engaged in addressing this problem, it may be difficult to see a quick solution to this challenge in Nigeria.However, we suggest the following as the way forward in meeting the housing need of low-income earners in Nigerian towns and cities.
First, as noted earlier, one of the key challenges of social housing provision in Nigeria is that the previous efforts have so far been based on top-down approach, instead of the bottom-top approach.Therefore, we contend that the prospects of low-income housing in Nigeria is contingent upon the adoption of community-based approaches, with the participation of local authorities and grassroots organizations such as cooperative societies and Community Development Associations (CDAs).The current thinking that mass housing schemes should be private sector-led as enunciated in the New National Housing and Urban Development Policy (NNHUDP) in 2002 can benefit low-income people if there are partnerships between government, housing cooperatives and other recognized grassroots organizations for the purpose of producing low-cost housing.These can help in reducing the overbearing influence of government agencies, and by extension the level of corruption and inefficiency in public housing in Nigeria.
Second, inadequate funding has been a recurrent problem in the implementation of mass housing programmes in Nigeria as previously highlighted.It is however, observed that some of the housing strategies that recorded marginal successes were based on mortgage acquisition.This is because the key problem with the low-income earners is that they lack the financial muscle to acquire completed housing units or to build houses of their own without one form of assistance or the other.To this end, subsidies and mortgage-based housing strategies hold the key to sustainable housing for low-income earners in Nigeria.It is therefore suggested that an intervention fund for low-cost housing (Social Housing Trust Fund) be established through appropriate legislation to provide mortgage facilities and housing subsides.Multi-national corporations, faith-based organizations and philanthropists should be encouraged to contribute to this fund as part of their corporate social responsibility, while a Board of Trustees for this fund should comprise men and women of proven integrity to ensure the judicious use of the fund in social housing provision in the country.
Third, it is very hard to believe that any tangible result will be achieved in the future through government direct involvement in the construction of walk-in homes for the people through designated ministries or agencies as envisaged in the NNHUDP.This is because the level of corruption in the public sector and construction industry in Nigeria may not allow low-income earners to benefit from such houses.Instead, government's involvement in direct production of housing units should be limited to assisted self-help approaches in SSS and CHS.These should be based on direct labour approach and the use of local building materials to reduce cost and improve affordability among the low-income earners.A good example is the Ogun State's Workers Housing Estate, Laderin, Abeokuta, as previously discussed.It is important that this type of housing scheme be embraced and extended to other low-income private sector workers across the country.
Lastly, in the present and near future, remedial measures are required to improve housing and environmental conditions of core areas and peripheries of Nigerian cities.This suggests that urban renewal or regeneration will continue to be part of future urban housing strategies in Nigeria.Going by the observation that previous attempts in urban renewal through slum clearance and resettlement have been fraught with controversies due to the lack of social content, there is a need to change this approach.The way forward in urban renewal as a strategy for combating slums in Nigerian cities is the adoption of bottom-top approach with effective participation of residents of designated areas to be subjected to renewal.This calls for the adoption of participatory approaches in which local authorities and residents play key roles in urban renewal process.This will ensure that those who are adversely affected in such schemes are provided with alternative housing and that such schemes did not further compound the already deplorable urban housing situation in Nigeria.

5.
This paper has examined urbanization and the challenges it poses in the area of housing for low-income earners in Nigeria.It has also explored the prospects of housing for low-income earners in the light of the high rate of urbanization in the country.The paper posits that in spite of poor economic growth and development, rapid urbanization with all its concomitant effects has been dramatic.Besides the fact that urbanization exacerbates urban poverty and lack of access to basic facilities as well as unemployment, urban housing provision is one of the most critical challenges posed by urbanization.Although access to adequate housing is a fundamental human right enshrined in the constitution of the Federal Republic of Nigeria, efforts so far made by governments in this country to make housing accessible to a majority of the people have not yielded the desired results.The paper notes that the lack of adequate understanding of the strategies to combat the deteriorating housing situation among low-income urban residents and the top-down approach to social housing provision have contributed to the current situation.It is suggested that as Nigeria continues to witness rapid urbanization, the future pathways for housing low-income urban residents in this country depend firstly, on core housing, SSS and settlement upgrading strategies, which allow low-income households and individuals to undertake the construction of their dwelling units incrementally over a period based on their income.Secondly, there should be mortgage-based approaches that involve active participation of governments at all levels, community-based organizations, housing cooperatives, multi-nationals and philanthropic organizations.

Table 1 :
Nigeria's Population growth and Urbanization (1921-2050)dwellers, and this rose to about 49.8 percent in 2010.Current estimate suggests that by 2050 about 75.42 percent of this country's total human population will be urban dwellers and that some cities, including Aba, Abuja, Benin City, Ibadan, Ilorin, Jos, Kaduna, Kano, Lagos, Maiduguri, Ogbomosho, Port Harcourt and Zaria among others will have populations over one million (UN-HABITAT Olujimi (2009)ed from various sources: Gbadagesin and Aluko (2010);Olujimi (2009); UN-HABITAT (2010), N.A. = Not Available; * = Projections.From Table1, it can be seen that in 1921, when the total population of Nigeria was about 18.72 million, around 4.8 percent were urban