All cities experience environmental problems to a lesser or greater degree, usually cause great obstruction to the developers that attempt to improve the urban environment. The brown agenda that obstructs this includes these issues: Pollution from a variety of sources, especially from industrial, domestic and transport services- pollution of the air, land and water is a major problem in most developing world cities. The drive of industrialization brings with it the inevitable problems, especially as legislation to protect the environment is often non-existent or arely enforced.
Air pollution is the most obvious threat-the causes are usually traffic, factories, incinerators and power plants-specially when the industrial plants are old. Air in Mexico City, Mexico, is so poor that breathing it is like smoking 60 cigarettes a day. Chemical pollution is also a problem-waste from power plants and overspills from fertilizers from the ground can leak into the water supply. Poisonous gas explosions are extremely dangerous-for example a gas explosion in Bhapol, India, killed 3300 people and seriously injured 150 000.
Leaking sewers are also a major threat to the water supply-for example the villages of Kanpur or Varansi, India, leak untreated sewage into the Ganga-spreading disease through the villages in India. Landfill sites and industrial waste, including oil and chemicals, are a main cause of water pollution. Sewage and waste disposal can hinder development. The huge increase of population in countries cause solids from paper, packaging and toxic waste to increase- liquid sewage and industrial waste both rise exponentially.
These all cause contamination and health hazards from oor systems of disposal, e. g rat infestations and water borne diseases such as Cholera in some cases. An example of the problem of sewage control in Calcutta, India-during the monsoon season sewage can be seen pouring down the side of the street where the drains are insufficient to cope. An example of an MEDC problem of waste disposal is in the `Bronx’, south of New-York-rubbish continually clutters the streets, just like in the squatter settlements in Rio de Janeiro, Brazil.
Rio faces many problems associated with waste-50% of people iving in favelas don’t have access to an indoor toilet-the sewage runs through open ditches and eventually runs up to street level creating an incredible hazard of disease etc. Dereliction of land can obstruct development-due to a number of reasons-many toxic leaks that enable a growth of development on the land, unsightly areas, abandoned areas where buildings are in ruins, e. g. Cairo, Egypt, the buildings decline but not restored-leaving them abandoned a huge safety hazard. Dereliction also occurs in MEDCs such as in the `Bronx’, New-York, during the 1970s landlords were burning own their properties to claim insurance money-the buildings are boarded up and left derelict and impossible to restore-resulting in brown field sites. Natural disasters such as flooding and landslides also can hinder development, along with problems generated by rapid urban sprawl, in particular loss of land and creation of wide areas of slums-e. g. Rio de Janeiro, Brazil. Favelas take up the land and development cannot take place.
Squatter settlements like the ones in India are also a major problem-legally they are not allowed to settle there but evelopment cannot take place due to their obstructions. In an urban area it is the low-income groups in the cities that suffer the most and these problems escalate as the size of the urban area increases-Mega-cities have enormous environmental problems and can be regarded as unsustainable, e. g. Los Angeles, Mexico City, Bangkok, Manila and Calcutta. The ways in which there problems have been tackled are as follows: Pollution can start to be resolved by shutting down old factories and importation of clean technology, e. g. filters, use of cleaner fuel, not coal or wood.
Cars can be fitted with catalytic converters, use of un-leaded petrol, movement from private transport to public-this is an example of green transport planning. This will reduce the release of harmful chemicals such as Carbon Monoxide (which can attach to the red blood cells and cause serious lung problems and even death), Nitrogen Oxide etc caused by the factors mentioned. Pollution levels can also be monitored and guidelines be released over the levels of pollution in certain areas. Sewage and waste disposal can be resolved by: improved public awareness-recycling etc. or example the Christians in Cairo, Egypt, sort through the rubbish and recycle the majority of the waste-however Muslims do not do this due to religious beliefs they hold about pig products. However, this is not always a good thing-the hospital waste is also dumped here-threatening disease etc on the people recycling the waste. Landfill sites, incineration plants and exportation of the waste to the areas (usually MEDCs to LEDCS though) can remove the problem of waste. Sewage pipes can be inserted to remove the problems of disease etc on places such as