The Madeira River reached a new all-time low on Friday (11): 19 centimeters.
The drought has forced residents of the Calama district, in Porto Velho, to develop new navigation strategies.
Fishermen use boat propellers to create "paths" in the mud.
The Madeira has been monitored by the Brazilian Geological Survey since 1967. Since then, the lowest level ever observed was 19 centimeters, on Friday.
With more than 3,200 kilometers of fresh water, the Madeira is one of the largest in Brazil and the world, in addition to the longest and most important tributary of the Amazon River.
The extreme drought does not only affect navigation.
There are reports that the impacts also hit fishing and agriculture hard.
Historically, October and November are the months when the Madeira is driest.
However, the river level began to reach historic lows in July; after that, the situation became even more critical.
Source: Amazon Agency