Toronto: Just over one-third of the world’s 246 longest rivers remain free-flowing, according to a study which found that dams and reservoirs are drastically reducing the diverse benefits offered by healthy rivers. A team of international researchers, including those from McGill University in Canada and World Wildlife Fund (WWF), assessed the connectivity status of 12 million kilometers of rivers worldwide.
The study, published in the journal Nature, provides the first-ever global assessment of the location and extent of the planet’s remaining free-flowing rivers. Researchers determined that only 21 of the world’s 91 rivers longer than 1,000 kilometres that originally flowed to the ocean still retain a direct connection from source to sea. The planet’s remaining free-flowing rivers are largely restricted to remote regions of the Arctic, the Amazon Basin, and the Congo Basin. “The world’s rivers form an intricate network with vital links to land, groundwater, and the atmosphere,” said lead author Gunther Grill of McGill’s Department of Geography.
