Dry wood The Rio Negro, a tributary of the Amazon, is one of the world’s largest rivers. In 122 years, the water level of no tributary of the Amazon has dropped so much. The Rio Negro dropped to 12.66 meters (41.5 feet) on Friday due to drought and wildfires, according to Brazil’s geological service. This is the shallowest state recorded since measurements were first taken in 1902. And researchers in the port city of Manaus fear water levels could drop further as the dry season continues through most of October.
“This is the most severe drought in more than 122 years of monitoring at the port of Manus,” port operations chief Valmir Mendonca told Reuters. The Rio Negro is a major tributary of the Amazon River and is a very important waterway. The river drains more than 10 percent of the Amazon River basin and is the sixth largest river in the world. It’s the world’s largest blackwater river, decaying plant matter gives the stream a characteristic dark color. But widespread drought has shrunk the Amazon’s Rio Negro and other waterways, creating environmental and economic crises.