Singapore is located at the tip of the Malay Peninsula at the narrowest point of the Strait of Malacca, which is the shortest sea route between India and China. Its major natural resources are its location and its deep-water harbor. Singapore Island, though small, has a varied topography. The center of the island contains a number of rounded granitic hills that include the highest point, the 165- meter Bukit Timah Peak. The western and southwestern regions are composed of a series of northwest to southeast tending ridges, which are low but quite steep. To the east is a large region of generally flat alluvial soils where streams have cut steep-sided valleys and gullies. The island is drained by a large number of short streams, some of which flow into the sea through mangrove swamps, lagoons, or broad estuaries.

The island originally was covered with tropical rain forest and fringed with mangrove swamps. Since the founding of the city in 1819, the natural landscape has been altered by human hands, a process that was accelerated in the 1970s and 1980s. By 1988, Singapore's land area was 49 percent built up, and forest covered only 2.5 percent. Three water reservoirs and their reserve catchment area, which preserves a fragment of the original tropical forest, occupy the center of the island. Extensive land reclamation between 1965 and 1987 increased the size of Singapore Island from 586 square kilometers to 636 square kilometers further reclamation was planned for the 1990s. Hills have been leveled, swamps drained and filled, and many of the fifty-odd small islets and reefs have been enlarged or joined to form new larger islands suitable for industrial uses. In 1989 three of Singapore's five oil refineries were on offshore islands, and other small islands were used for military gunnery or as bombing ranges. Some of the larger streams were dammed at their mouths to form fresh-water reservoirs, and the major stream courses through built-up areas were lined with concrete to promote rapid drainage. Throughout the 1970s and 1980s, the municipal authorities made great efforts to establish parks and gardens as land became available and to plant tens of thousands of ornamental trees and shrubs, thus completing the transformation of the natural landscape.

Singapore is two degrees north of the equator and has a tropical climate, with high temperatures moderated by the influence of the sea. Average daily temperature and humidity are high, with a mean maximum of 31° C and a relative humidity of 70 to 80 percent in the afternoon. Rain falls throughout the year, but is heaviest during the early northeast monsoon from November through January. The driest month is July in the middle of the southeast monsoon. The intermonsoon months of April-May and October are marked by thunderstorms and violent line squalls locally known as Sumatras. The average annual rainfall is 237 centimeters, and much of the rain falls in sudden showers. Singapore is free from earthquakes and typhoons, and the greatest natural hazard is local flash flooding, the threat of which has increased as buildings and paved roads h 1000 have replaced natural vegetation.

In spite of the high rainfall, Singapore's small size and dense population make it necessary to import water from Malaysia. The water, from reservoirs in upland Johor, comes through an aqueduct under the causeway linking Singapore with the Malaysian city of Johor Baharu. Singapore also supplies treated water to Johor Baharu, which in 1987 took about 14 percent of the 1 million cubic meters treated by Singapore each day. Singapore has responded to this dependence on a foreign country for water by expanding its reservoir capacity and constantly urging household and industrial users to conserve water.

Singapore's rapid economic growth in the 1970s and 1980s was accompanied both by increased air and water pollution and by increasingly effective government efforts to limit environmental damage. The government established an Anti-Pollution Unit under the Prime Minister's Office in 1970, set up the Ministry of the Environment in 1972, and merged the Anti-Pollution Unit with that ministry in 1983 to ensure unified direction of environmental protection. The new unit, subsequently renamed the Pollution Control Department, had responsibility for air and water pollution, hazardous materials, and toxic wastes (see Government Structure , ch. 4). Singapore first moved to limit air pollution, closely monitoring oil refineries and petrochemical complexes and limiting the sulfur content of fuel oil for power plants, factories, and diesel motor vehicles. Because motor vehicles were the main source of air pollution, the government required emissions controls on engines and reduced (but not eliminated) the lead content of gasoline. The government also acted, partly for environmental reasons, to restrict private ownership of automobiles through very high (175 percent) import duties, high annual registration fees, and high charges for the entry of private automobiles to the central business district.

Between 1977 and 1987, the Ministry of the Environment carried out a major program to clean up rivers and streams by extending the sewer system, controlling discharges from small industries and workshops, and moving pig and duck farms to resettlement areas with facilities to handle animal wastes. The success of the program was demonstrated by the return of fish and aquatic life to the lower Singapore and Kallang rivers. Singapore, the world's third largest oil refiner, also acted to prevent the pollution of coastal waters by oil spills or discharges from the many large oil tankers that traversed the Strait of Malacca. The Port of Singapore Authority maintained oil skimmers and other equipment to clean up oil spills, and a comprehensive plan assigned both the oil companies and Singapore's armed forces responsibilities for dealing with major oil spills.

Singapore's environmental management program was intended primarily to ensure public health and to eliminate immediate hazards to citizens from toxins. Protection of the environment for its own sake was a low priority, and the government did not respond to local conservation societies' calls to preserve tropical forests or mangrove swamps. The pollution control laws gave the authorities wide discretion in dealing with offenders, and throughout the 1970s and 1980s penalties usually were light. Enforcement of the laws often reflected an appreciation of the economic benefits of polluting industries and provided time for industrial polluters to find ways to limit or eliminate their discharges.

Data as of December 1989