According to the United Nations Economic Commission for Latin America and the Caribbean –ECLAC-, the region has experienced unprecedented urban growth in the past four decades, increasing from 56.4% of the population living in cities over 100,000 inhabitants in the late 1970s to 79.5% in 2008 (ECLAC, 2009). Rural-urban migrations, which is a factor of growth of urbanisation alongside net in-migration, net natural population growth and changes in administrative boundaries, were influenced by factors as the implementation of Import Substitution Industrialisation -ISI- policies13 in the 1970s and structural adjustments policies implemented in
13 Import substitution industrialization (ISI) is a trade and economic policy started in the late 1930s
that promoted replacement of foreign imports with local production. ISI runs under the logic that a country should try to reduce its foreign dependency through national manufacturing of industrialized products (Gerber, 2007).
the 1980s. Such policies in countries like Colombia were also affected by internal conflicts and violence. According to Baer (1972) a widening in the rural-urban gap, although of a more economic than demographic nature, was experienced by Latin American cities as a result of ISI policies given their focus on modernisation of agriculture and incentives to urbanisation. In the decades between 1950 and 1980, Latin American countries experienced large migrations from the countryside to rising urban agglomerations. Rapid increase in urban population, although far more stable nowadays than in the period before the structural reforms of the 1990s, had serious implications in relation to social exclusion, vulnerability and disorganised urban growth (Gilbert, 1996; Cohen, 2004; UN-HABITAT, 2012). This translates, in terms of transport development, in enormous challenges for the provision of accessibility to local services, urban amenities and work opportunities, as well as in limited empowerment of urban and peri-urban citizens to overcome increasing distances and physical challenges for interacting with the city (Keeling, 2004).
Several authors have argued that as a result of structural adjustment policies implemented in the 1990s quality of life in most major Latin American cities experienced a sharp decay in relation to the 1970s (Gilbert, 1996; Stiglitz, 2003; Rodrik, 2006). In Colombia, 78.5% of the population living in cities, and 18% lived in informal settlements in 2009 (ECLAC, 2009). Urban expansion in the last decades of the twentieth century led to an increase in socio-economic segregation as well as growing spatial segregation between wealthier and poorer households in cities where jobs and services tended to be physically concentrated close or in city business districts (Gomez et al., 2015). According to Clichevsky (2000), economic disparities led to marginality of specific social groups, which translates into a lack of public amenities, security, and conditions that worsen dependency on motorised transport. The Latin American city is characterised by deficits in urban infrastructure and public services that confront citizens with increasing levels of insecurity, both in relation to crime and road-related
hazards, and decreasing quality of the environment due to noise and air pollution. This aggravates spatial polarisation between high and low- income groups has more recently led to intensification in the development of gated communities for the elite and increase in the vulnerability of the poor in informal neighbourhoods (Caldeira, 2000).
Inappropriate land regulations, unclear institutional arrangements, inadequate enforcement, political corruption, changes in levels of poverty and extreme poverty14, and largely variable approaches to social housing
from many Latin-American governments between the 1970s and 1990s increased the rhythm of development of informal housing in the region (Clichevsky, 2000; Gilbert, 2009). These developments were often located in the outskirts of already large cities, sometimes in neighbouring municipalities, generating processes of conurbation and urban expansion. Given conditions of higher affordability of informal settlements, the region witnessed an increase in illegal or unregulated developers that divided large areas of private land into plots that local migrants and new in-migrants to the cities bought and developed through self-help construction (Chant & McIlwaine, 2009; UN-HABITAT, 2012). Occupation of informal developments and low-cost housing in emergent neighbourhoods in growing cities was also incentivised by a growing demand for rental housing, particularly from poorest in-migrants, unable to locate in the city centres (Gilbert and Ward, 1982; Edwards, 1982). Renters frequently accounted for up to half of the total families in several low-income informal settlements in large cities in Latin America in the late 1970s, a phenomenon that persists in many informal neighbourhoods in the region today (Gilbert and Ward, 1982; UN-HABITAT, 2012). Rapid increase in population in informal neighbourhoods resulted in worsening of urban poverty and
14 According to data from the Inter-American Development Bank (Londono & Szekely, 1997), during
the 1970s poverty experienced a sharp decay in most of the region. However, during the 1980s poverty rates increased, reaching over 34% of people experiencing moderate poverty and nearly 16% under extreme poverty. These numbers were reduced moderately during the 1990s.
vulnerability as informal housing for low-income communities is often characterised by generalised lack of infrastructure and sanitary facilities, and precariousness in construction materials and techniques.
Migration patterns identified above, in combination with a relatively weak local industry and specialised job markets in large cities, have another unintended effect on social inequalities and differences in access to opportunities for both low-income citizens and new migrants. The majority of the poor in large cities of Latin America resort to work in activities with variable or centralised locations, becoming inextricably reliant on motorised transport (Portes, 2005). In cities like Bogotá, activities like street-vending, occasional service provision, domestic services and construction work take place at multiple or variable locations, which in turn translates in larger travel expenditure from low-income areas, usually located in the city outskirts in comparisons with better-located areas and higher-qualified individuals with access to other opportunities. Economic activities of low- income populations are commonly managed informally, and are largely dependent on unqualified labour force. According to Perry (2007), about 57% of the employment in Latin-American cities is produced in the informal sector, becoming an attractive source of employment for poor in-migrants in large urban agglomerations in the region.