Rural to urban migration, also known as urbanisation, is a growing concern for many countries as people continue to leave the countryside to seek employment in cities. Almost all countries experience this phenomena, and in some countries, as much as 6 per cent of the population may move from a rural area to a city within a five-year period, according to the CIA's World Factbook. Cities struggle to keep up with the demands of an increasing population, resulting in difficulties for migrants and existing residents.
As more people move from the countryside into cities, affordable housing becomes difficult, if not impossible, to obtain. Not only do new migrants often find it difficult to find available housing, but they may find that they are priced out of the market as the demand for housing -- and thus the price -- increases with the population. The result is that migrants may rent apartments with several other individuals or families, leading to overcrowded living conditions. As the number of people living in the city increases, other effects of overcrowding become apparent.
Higher Crime Rate
Overcrowding in cities generally leads to a higher crime rate. The gap between rich and poor often widens, and slums may be formed. The city may not have the funding to support the level of law enforcement that is required for a rapidly increasing population. In the Philippines, it is estimated that over 61 per cent of the population of Manila are squatters. The resulting instability of living conditions in this area has resulted in increased juvenile delinquency, family violence, theft and other social problems. The problems that Manila is experiencing due to rural to urban migration are not unique. They are replicated in many other cities around the world.
Strain on Urban Infrastructure
Instanbul is an example of a city where population has outstripped infrastructure. Due to a large influx of rural migrants over the years, officials recognise that the city needs significant upgrades to its water and transportation infrastructure. However, addressing these two issues will cost approximately 10 million dollars, according to the Asian Development Bank. This problem is not unique to Istanbul. Many cities around the world struggle with infrastructures that fail to meet the needs of a growing population.
An increase in population results in an increase in economic activity. This amplification of industry results in increased energy use and industrial pollution. Nearby rivers can become polluted with runoff from manufacturing facilities, while the skies grow smoggy with the detritus from smokestacks and a greater number of automobile emissions. The denizens of Mexico City, a model of urbanisation that has occurred at a faster rate than is sustainable, live with a level of pollution that is responsible for 4,000 premature deaths every year, according to Molina Center for Strategic Studies in Energy and the Environment. This is due to the 600 cars that are added every day to Mexico City's streets -- a result of the ever-growing population.