Environmental hazards of shantytowns

DEFINITION: Communities of people among the lowest socioeconomic classes housed in small, poorly built dwellings

The environmental hazards faced by the residents of shantytowns include disease caused by polluted water and air, exposure to industrial waste, and vulnerability to natural disasters.

Millions of people throughout the world cannot afford housing that is safe, sturdy, and reasonably spacious. While inhabitants of poor housing in sparsely settled farm or forest regions run certain risks, the environmental dangers attached to living in poor housing multiply when many such dwellings are huddled closely together in urban areas.

The most acute housing problems are found in the world’s developing nations. Since the mid-twentieth century, millions of migrants from rural areas have crowded into these nations’ cities. The jobs the cities provide are a powerful magnet for citizens whose customary farming life no longer sustains them. Indeed, in many cases, the farmlands have been ruined by destructive processes such as deforestation or soil erosion. While the cities seem to promise a better life, most migrants arrive unable to afford the most basic housing with amenities. They are left to build their own shelter from whatever materials they can scavenge.

Statistics show the importance of shantytowns in housing these poorer residents. In Bogotá, Colombia, more than one-third of the population lived in self-built housing in 2021, and 60 percent of the people in Dar es Salaam, Tanzania, lived in such dwellings. In Addis Ababa, Ethiopia, the proportion was close to 85 percent. It was estimated that in most of the cities of developing nations, 70 to 95 percent of all new housing is illegally built and held. According to Habitat for Humanity Great Britain, the world’s largest slum was in Orangi Town, Karachi, Pakistan. In 2017, the slum housed more than 2.4 million people. Approximately 1.1 billion people lived in urban slums in 2022, according to the United Nations, and this number was expected to grow significantly, with projections indicating a rise to 2 billion by 2030 and possibly 3 billion by 2050.

The flimsy houses that make up shantytowns usually occupy land that is unsuitable for other purposes. Shantytowns spring up on floodplains, steep hillsides, lots adjacent to contaminated industrial sites, and rail or highway rights-of-way. In Manila, Philippines, some 30,000 squatters lived for more than forty years on and around Smokey Mountain, a municipal dump that the squatters scavenge for materials to sell. In Cairo, Egypt, some 500,000 people lived in a squatter community built amid ancient mausoleums. Their shacks are constructed of corrugated tin, packing crates, mud bricks made on-site, and similar materials.

Environmental Hazards

The greatest environmental dangers in these communities stem from the lack of sufficient drinking water and the lack of infrastructure to remove human and household wastes. Few residents have water piped into their houses, so they must buy water from street vendors or manually carry it from a common spigot shared by many people. With either source, the expense or effort of obtaining water means that households seldom have enough for healthy day-to-day living. In some cases, residents may use water from surface sources or shallow wells; both are likely to be contaminated with biological or industrial wastes.

Without sewage treatment and disposal systems, disease vectors get cycled back into the immediate environment. On-site methods such as septic tanks or pit latrines, which are adequate for low-density conditions, break down in crowded settlements. Waterborne diseases such as dysentery, cholera, and infant diarrhea are common in shantytowns. Standing water and waste also shelter mosquitoes, which spread malaria. Dumped garbage attracts rats.

Industrial pollutants are another hazard. Many shantytowns are built next to factories at which the inhabitants work, and most such sites generate contaminants. This is doubly true of factories in developing nations, where public awareness and legal regulation of environmental toxins are much weaker than in the United States. The chemical disaster in Bhopal, India, in 1984 killed mostly low-income people who lived near the Union Carbide pesticide plant that leaked toxins into the air. Shantytown dwellers who live beside highways are subject to a constant barrage of fumes from motor traffic.

Many added environmental stresses arise in these communities. Families of four, five, or more people living in a single room readily exchange airborne infections. A significant percentage of children in the slums of Kanpur, India, were estimated to have tuberculosis. The most dramatic threat, however, came from natural disasters. Squatter settlements on bare hillsides and houses built of mud or flimsy materials are vulnerable to hurricane, flood, or earthquake damage.

Although their impacts on surrounding regions are hard to separate from more general urban pollution, shantytown living conditions do affect wider areas. Fecal material and garbage from urban slums travel downstream in rivers for hundreds of miles. Yards of packed dirt and a lack of drainage systems slow the absorption of rainwater into the soil. The costs of residents’ excess illnesses and deaths, let alone time wasted in daily tasks such as hauling water from a faraway spigot, are further drains on developing countries’ limited resources.

Shantytowns are a rational response to housing needs by people who cannot afford standard houses. Merely bulldozing the shanties or forcing their residents out seldom works; such actions simply compound problems. Providing squatter villagers with a basic infrastructure of piped water and sewage disposal immediately upgrades their living conditions. It is also much cheaper, liter by liter, than the hauled water that slum dwellers buy. When such systems are provided, shantytown residents may further improve their homes with materials at hand. Economic, political, and cultural pressures on local governments often prevent such plans from going forward, however. It helps if shantytown residents first gain legal title to their dwellings and a modicum of political power. Given the urban growth rates and economic problems in developing nations, however, these problems may not be solved for many years.

Shantytowns are also found in developed countries, but in such nations, they constitute a much smaller proportion of the total housing stock than they do in developing nations. Because the settlements are smaller and attention to public health issues is greater, the environmental hazards that the residents of these shantytowns face are less overwhelming, although they are still significant.

Bibliography

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