Catalog

	Table of Contents
p. 7 of 57 BACK | NEXT I. The Changing Environment Economic Transformation State of the Environment in the Region Land and Forests Water Resources Air Quality Urban Population Counting the Toll Looking Ahead II. Driving Forces of Change III. Options and Opportunities IV. Toward Policy Integration V. Call to Action

Asian Environment Outlook 2001 : I. The Changing Environment : State of the Environment in the Region

---

Urban Population

The urban population in Asia is growing significantly. By the year 2020, an additional 1.5 billion people will be added to Asia’s urban centers (ADB 2000e). Such a massive number of people will need adequate infrastructure and services, prominent among them being water supply, housing, and sanitation facilities. An adequate facility for solid waste disposal is required to ensure an urban environment conducive to the well-being and productivity of residents.

Declining urban environmental quality has occurred despite considerable efforts in urban planning during the last three decades. Urban development master plans for most cities have been prepared for wastewater collection and treatment, drainage, solid waste management, land use, and (in a few cases) air quality management. Few of these plans have been implemented, mainly because of the lack of management, control, and financial resources. For example, the first wastewater management plan for Bangkok prepared in 1965 required an investment of a few hundred million dollars. A meaningful level of wastewater management throughout the city today would cost more than 3 billion dollars. As a result of the lack of investment, most major urban areas have limited environmental infrastructure and the costs of meeting these urgent infrastructure needs are phenomenal. Other cities, such as Ho Chi Minh City and several of the large PRC and Indian cities, are serviced today by infrastructure designed to meet the population and industry needs of the mid-1960s. A similar situation, although requiring less capital, applies to solid waste management. Many Asian cities have dramatically improved solid waste collection but at the turn of the century many found that they had no place to dispose of the wastes. Waste minimization efforts would reduce capital investments required for wastewater and solid waste conveyance and treatment, but the capital requirements are still huge.

For most large cities in the region, sustaining an adequate and safe supply of water for domestic and industrial uses is a major problem. Virtually all surface waters in the region have become severely degraded upon entering urban waterways (see Box 1-9). Only in limited cases has surface water quality demonstrably improved over time. The major source of water pollution in some cities is domestic waste. However, there are many watercourses where the industrial pollution load is high with “black spot” industries that cause localized problems. Sewer systems in many major cities in the region are inadequate to support a high-density urban environment. In most cities, sewage is often discharged directly to drains or waterways, or at best, is disposed of in individual septic tanks that are not regularly emptied or maintained. The result is untreated overflow of domestic wastewater that pollutes both groundwater and watercourses.

Another major urban environmental issue is flooding and land subsidence. For example, Bangkok is in a flat lowland area associated with a typical monsoon rain regime whose runoff frequently exceeds the Chao Phraya river drainage capacity, a problem that is exacerbated by the progressive filling in of the “khlongs” (or canals) as the urban area expands. Flooding is therefore a historical problem and one of the most difficult and costly problems to resolve. Further, excess groundwater extraction needed to supply freshwater to urban and industrial areas produced remarkable land subsidence effects in parts of Bangkok (measured during the 1980s at 0.6 to 5.1 centimeters per year). Land subsidence increased the probability as well as worsened the impact of flooding. Similar conditions are reported in some PRC river basins, where availability of clean surface water has reached crisis conditions resulting in the massive drawdown of water tables (Gunaratnam 2000).

Industrial growth and urban expansion have greatly contributed to and increased the generation and accumulation of solid and hazardous wastes in many DMCs, outrunning the collection efficiency and disposal capacity of many municipalities. Some cities have significantly improved solid waste management. For example, Kolkata, which generates about 2,500 metric tons of waste per day, has developed effective collection and disposal systems that capture 95 percent of the waste stream. Most cities collect 70 to 80 percent of solid wastes, leaving an average of about 1,000 tons per day uncollected in cities such as Jakarta and Manila. Other cities such as Dhaka and Karachi collect less than 50 percent. The balance ends up in drains and rivers, exacerbating flooding, or in vacant lots or roadsides, where it impacts public health by providing habitat for rodents, flies, and other disease vectors.

Urban environmental challenges are unique in the Pacific islands (see Box 1-10). Except for Fiji Islands, common features of these countries include poverty, remoteness and isolation, openness, susceptibility to natural disasters and environmental change, limited diversification, and limited capacity. Traditional ways of managing natural resources are disappearing. The most crucial environmental issues are in the areas of (i) natural resources conservation — because of rapid deforestation and unsustainable and destructive exploitation of marine and mineral resources; (ii) waste management and pollution prevention — because of lack of systematic waste disposal, pollution of surface water and groundwater, and lack of management of toxic wastes including pesticides, waste oil, and heavy metals; and (iii) climate change and sea level rise— because most people in these countries live in low-lying coastal areas that are particularly vulnerable to climate change.

Back Air Quality	Next Counting the Toll