Newsletter and Technical Publications
<International Source Book On Environmentally Sound Technologies
for Wastewater and Stormwater Management>
3. Asia (Pacific)
The Asia Pacific region is an enormous and extraordinarily diverse region,
and is characterised by widely varying practices. Urbanisation has been particularly
pronounced in the Asia Pacific region in the second half of the 20th century.
The urban population in Asia was 1.15 billion in the year 1995 accounting for
about 33% of the world' s total population. By the year 2025, Asia will become
predominantly urbanised with an urban population of 2.5 billion or 55% of the
world’s total population. This anticipated increase represents a massive
and rapid economic and demographic transformation.
Although the Asian and Pacific Region, as a whole, is experiencing rapid urban
growth, it is still predominantly rural. The urban growth rate in the region
remained high throughout the 1970-90 period: almost one-third higher than global
rates over the same period (Economic and Social Commission for Asia and the
Pacific "ESCAP" 1993). During the 1980s, urban populations in the
developing countries of the region grew at rates of between 3.0 and 6.5 per
cent per annum (see table 3.1), with a regional average of 4.7 per cent per
annum, the second fastest urban growth rate in the world.
Table 3.1: Urban Population Trends in Selected Countries/Territories
of the Asia and Pacific Region, 1980-2020. (for
In most countries of the Asia and Pacific Region, the proportion
of people who do not have access to proper shelter, clean and reliable water,
and adequate sanitation in rural areas is higher than in cities and towns.
Although, urban areas have better basic infrastructure and services than rural
areas, the urban poor, who generally inhabit low-income settlements and slums
within cities, have limited access to land close to centres of employment. They
are also denied regular and full access to basic services and suffer most from
the adverse effects of crowding, poor water supply and sanitation.
The major environmental problems facing the Asia and Pacific
Region during urbanisation are increasing pollution levels due to concentrated
discharge of residuals (gaseous, liquid and solid wastes) into the environment,
and destruction of fragile ecosystems in the process of urban development. These
problems warrant major concern on three counts: firstly, the prevailing pattern
and trend of urbanisation is increasingly more material and energy intensive;
secondly, the discharge of pollutants in cities is particularly harmful because
they are concentrated; and thirdly, the financial, institutional, technological,
and infrastructure facilities available to help control these problems in the
region are often found to be inadequate.
One of the greater threats to human health in the developing
world is the lack of adequate water and sanitation services. The proportion of
the urban population covered by sanitation services is even smaller. More than
420 million urban residents do not have access to even the simplest latrine.
Many resort instead to open defecation on land or in waterways. The Asia Pacific
region urban poor fit in to this description.
In term of their approach to wastewater and stormwater
management, it is useful to characterise these countries with respect to the
rapid urbanisation in region. They range from the economically more advanced
urban centres of Australia, Hong Kong, Japan, Korea (more developed countries)
to middle and low income cities of East Asia and Pacific region (developing