- Singapore has moved from landfill to incineration:
- Singapore is an islandoff Malaysia. It is almost entirely The amount of waste produced in Singapore increased from 1,260 tonnes per day in 1970 to 8,400 tonnes in 2015. Land is scarce, so waste management is important.
- In the 1960s and 1970s, most waste was set to landfill sitesaround the city. However, in the late 1970s, the government changed their main waste disposal method to incineration with energy recovery.
- The first incineration plant was constructed in Today, there are four plants across the city, which provide about 3% of Singapore’s energy needs.
- Each incinerator is fitted with pollutioncontrol systems to limit greenhouse gas emissions.
- Singapore now has only one landfill site, Semaku, which was built on reclaimed land between two small islands.
- It is lined with an impermeable membraneand a layer of clay to prevent leaching of chemicals. Once each area of the site is full, it is covered with topsoil to support vegetation. It is now home to rare species.
- Singapore’s waste disposal systems are effective. In 2015, only 2% of wastewas sent to landfill – 38% was incinerated and 60% was Only waste that can’t be recycled or burnt goes to landfill.
- However, pollution control systems cannot remove allharmful emissions from incinerators, and incinerators only last around ten years before they need to be replaced. The current landfill site is expected to be filled by around
Atmospheric Pollution
- In many developedcountries, reliance on fossil fuels is decreasing, and use of less-polluting energy sources is increasing. As a result, air quality in many cities has improved since 1950.
- However, car ownershipis increasing, and congestion can cause significant atmospheric pollutions.
- Many developingcountries and emerging economies still rely heavily on fossil fuels to meet their energy needs. Increases in industrial activity and car ownership, combined with a lack of regulation of emissions, means that atmospheric pollution is often severe.
- In many developed countries, there are strategiesto limit air pollution, such as promoting ‘green’ modes of transport.
- In the developing world, there has been some progresstowards reducing urban air pollution such as most countries have phased out the use of leaded petrol although progresses
Water Pollution
- Cities have a high population density, so they produce a lot of waste. This includes wastewaterand sewage, as well as oil and metals on road surfaces from cars. These pollutants can enter
- Many cities have a high concentration of factories,which may discharge industrial waste into watercourses.
- Water pollution can cause damageto ecosystems, and contaminated drinking water can cause health problems such as dysentery and cholera.
- Water pollution can be managed through lawsto stop discharge of untreated waste from industries and provision of plants to treat wastewater. Strategies, such as catchment management and SUDS can also help.
- In developedcountries, there are strict regulations about discharge of untreated water, and water quality is
- However, litterdropped in or around water and pollutants in surface runoff still cause pollution.
- In many developingcountries and emerging economies there are few regulations and inadequate provision of treatment facilities.
- This means that untreated industrial waste and sewage often enter watercourses and water pollution is
Urban Dereliction
- Urban derelictionhappens when economic activity in urban areas declines and buildings become run down. It often follows a pattern:
- The movementof manufacturing overseas and the decentralisation of industry leads to industrial decline. Many unemployed people leave urban areas in search of work.
- If lots of people leave the area, shops may be forced to close, and services go into decline. As industry, people and services move out, they leave empty buildings.
- Empty buildings and derelict areas often have problems with vandalism, graffitiand
- Urban dereliction is more commonin developed countries where widespread deindustrialisation has occurred.
- Strategies to manage urban dereliction include the redevelopmentof former factories into commercial and residential properties, the construction of new housing in derelict areas and the creation of green spaces.
- However, some cities lack investmentand large areas remain derelict.