Municipal Wastewater (Sewage)

Throughout the world, excess nutrients from agricultural runoff and municipal or private sewage is overfertilizing ocean and coastal areas. It has caused "dead zones", where virtually no life can exist in the oxygen-less water. Investigations taken in Asia reveal that 30 domestic sewage treatment plants, 65 tributaries and 155 main sections on the Huaihe River in 21 cities and 91 counties and districts along the river area often illegally release excessive wastes into the river. For more information, click here for a report from Peoples Daily Online.

Sewage dumping also poses a widespread threat to coastal waters. More than 2,600 beaches in the United States were closed in 1992 due to sewage pollution. Athens, the capital city of Greece, with a population of 3,693,000 (1995) people, is just one of many cities worldwide that dumps untreated municipal sewage into the sea. (Marine Pollution and Overfishing) Water resources in Lagos for domestic, industries and commercial is becoming scarce as a result of pollution of water bodies by wastewater, which contains heavy metals, bacteria (pathogenic) etc. Sewage can fertilize parts of the ocean to death. It brings phosphates and nitrates into the water and causes blooms of algae so prolific that the oxygen is depleted to the point where a 'dead' zone results.

Africa's rich coastal and marine areas are under threat from pollution, an estimated 38 per cent of coastal ecosystems, such as mangrove swamps and coral reefs, are under threat from developments like ports and the growth of coastal settlements and their sewage discharges. (UN Chronicle: Global warming challenges African Development.)