New study in Nature: Just one-third of the world's longest rivers remain free-flowing

Infrastructure development and other man-made changes have already fragmented or disrupted two-thirds of Earth’s longest rivers. Dams and reservoirs are the leading contributors to connectivity loss in global rivers. A team of 34 international researchers from World Wildlife Fund (WWF), McGill and other institutions assessed the connectivity status of 12 million kilometers of rivers worldwide, providing the first-ever global assessment of the location and extent of the planet’s remaining free-flowing rivers.
Source: EurekaAlert, https://www.eurekalert.org