On the last day of November and compared to the previous month, there was an increase in the volume stored in seven river basins and a decrease in five.

The Ribeiras do Barlavento basin had the lowest water availability at the end of November, with 14 percent. This basin is in red, i.e. with values well below the average.

The basins of Ave (25.2 percent), Lima (28.4 percent), Sado (40.3 percent), Mira (40.6 percent), Oeste (43.9 percent), and Arade (49.1 percent) also had the lowest water availability at the end of November.

According to SNIRH data, the Guadiana (60.2 percent), Cávado (61.1 percent), Mondego (64.4 percent), Douro (67.8 percent) and Tagus (74.6 percent) basins had the highest levels of storage at the end of November.

The November 2020 storage per river basin is lower than the November storage averages (1990/91 to 2019/20), except for the Douro, Tagus and Arade basins.

Each river basin may correspond to more than one reservoir.