As the demand for water grows with population and the economy, water supplies will be increasingly polluted from untreated sewage, from industrial discharges, and from salt-water intrusion of overexploited water tables.
In Jakarta, it costs $20M to $30M annually to boil water for home use. In Manila Bay, heavily polluted by sewage, fish catches have dropped 40% in the last decade. Fish catches near cities in India and China also have experienced major declines. Of Taiwan’s 20 million people, less than 1 million are served by sewers. Each day in Hong Kong, about 1 million tons of sewage and industrial effluent pour untreated into the sea – a volume to fill 500 Olympic swimming pools, according to Hong Kong officials. Projecting to 2025, water shortages will affect India, China, North and South Korea, Cambodia, Thailand, Vietnam and the Philippines.
Water disputes have affected international relations for years. Although an agreement was reached in 1996, India and Bangladesh have disagreed on the sharing of the waters of the Ganges for more than 20 years. Greater numbers of international disputes will arise and be more difficult to resolve as populations increase and economies grow, thereby placing a greater demand on scarce resources.
A domestic resource allocation problem that is common to the Pacific Islands soon will prevail over Asia: high-use agriculture will compete with populations for scarce water supplies. While more than 80% of the water consumed in Asia is used for agricultural purposes, 60 to 75% is lost to evaporation before reaching the crops. A technological solution may be to encourage the use of water-efficient drip irrigation techniques, which are employed in less than 1% of all irrigated areas.
Projecting to 2025, water shortages will affect India, China, North and South Korea, Cambodia, Thailand, Vietnam and the Philippines, also Indonesia especially Java island.