Aerial view of the Congo River. In the majority of rivers in the Global South water pollution has worsened since the 1990s. © UNEP

Aerial view of the Congo River. In the majority of rivers in the Global South water pollution has worsened since the 1990s.
Photo: © UNEP

Global water quality causes concern

While the quality of surface water has noticeably improved in recent decades in many parts of the developed world, water pollution in the majority of rivers in Africa, Latin America and Asia has increased, as a new UNEP report shows.


Water pollution has worsened since the 1990s in more than 50 per cent of river stretches in the Global South. This is the result that the study “A Snapshot of the World’s Water Quality: Towards a global assessment”, arrives at. The study is the work of more than 40 authors who were commissioned by the United Nations Environment Programme (UNEP), and it is based on hundreds of thousands of data sets on water quality world-wide provided by the United Nation’s Global Environmental Monitoring System (GEMS). The scientists analysed the causes of detrimental modifications in the quality of bodies of water and assessed the impacts that these could have on human health, food security and the state of aquatic ecosystems.

“Water pollution is a very serious problem in Latin America, Africa and Asia which is leading to a new form of water scarcity,” says lead author Joseph Alcamo, formerly UNEP Chief Scientist and today Managing Director of the Center for Environmental Systems Research (CESR) at the University of Kassel, Germany. “Deteriorating water quality restricts the use of freshwater resources, limiting them where they are needed most badly.”

Some of the main findings of the study:

  • Severe pathogen pollution already affects around one-third of all river stretches in Latin America,
    Africa and Asia. The number of rural people at risk to health by coming into contact with polluted surface waters may range into the hundreds of millions on these continents. Among the most vulnerable groups are women and children.

  • Severe organic pollution already affects around one out of every seven kilometres of all river stretches in Latin America, Africa and Asia. The high level of organic pollution and its increasing trend is of concern to the state of the freshwater fishery and therefore to food security and livelihoods. Groups affected by organic pollution include poor rural people who rely on freshwater fish as a main source of protein in their diet and low-income fishers and workers who depending on freshwater fishery for their livelihood.

  • Severe and moderate salinity pollution already affects around one-tenth
    of all river stretches in Latin America, Africa and Asia and is of concern because high salinity levels impair the use of river water for irrigation, industry and other purposes. Groups affected by salinity pollution include poor farmers that rely on surface waters as a source of irrigation water for their smallholdings.


However, the study also points out that most river sections in these continents are still in a qualitatively good state. The authors maintain that nowadays, severe pollution can be tackled with a wide range of technical and management measures.


(CESR/sri)

More information

Publication: UNEP 2016. A Snapshot of the World’s Water Quality: Towards a global assessment. United Nations Environment Programme, Nairobi, Kenya.162pp.

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