Urbanization in Asia and the Pacific is predicted to grow at an average
rate of 2.4 per cent per annum between 2001 and 2015. The current level
of urbanization ranges from a low of 7.1 per cent in Bhutan to 100 per
cent in Singapore and Nauru. Australia and New Zealand is the most urbanized
subregion (85 per cent) and South Pacific the least (26.4 per cent). In
seven countries in the region (Australia, Japan, Nauru, New Caledonia,
New Zealand, Republic of Korea and Singapore) the level of urbanization
is more than 75 per cent, while the 12 megacities in the region - Beijing,
Calcutta, Delhi, Dhaka, Jakarta, Karachi, Metro Manila, Mumbai, Osaka,
Seoul, Shanghai and Tokyo - accommodate 12 per cent of the urban population
(United Nations Population Division 2001 and UNESCAP and ADB 2000).
In some of the larger cities, excluding those in Australia and New Zealand,
up to 60 per cent of the inhabitants live in informal settlements, with
a population density of up to 2 500 persons per hectare (Ansari 1997).
These settlements suffer from a lack of infrastructure and services such
as water supplies, sewerage, drainage, roads, health care and education.
The major urban environmental issues in the region are air pollution
and inadequate services.