As cotas do rio Negro vem sendo medidas, diariamente, desde setembro de 1902. O presente trabalho baseou-se em dados colhidos entre os anos de 1903 a 1999. As cinco maiores enchentes aconteceram em: 1953 (29,69m), 1976 (29,61m), 1989 (29,42m), 1922 (29,35m) e 1909 (29,17m). As cinco maiores vazantes aconteceram em: 1963 (13,65m), 1906 (14,20m), 1997 (14,34m), 1916 (14,42m) e 1926 (14,54m). Os cinco menores valores de cotas máximas foram em: 1926 (21,77m), 1912 (24,84m), 1992 (25,42m), 1964 (25,91m) e 1980 (26,00m) e os cinco de cotas mínimas foram em: 1926 (21,77m), 1912 (24,84m), 1992 (25,42m), 1964 (25,91m) e 1980 (26,00m). As cinco maiores diferenças alcançadas em um mesmo ano entre as cotas máximas e mínimas aconteceram em: 1997 (14,62m), 1909 (14,13m), 1953 (12,62m), 1952 (12,44m) e 1916 (12,21 m) e as menores aconteceram em: 1912 (05,45m), 1968 (06,10m), 1985 (06,53m), 1974, (06,62m) e 1986 (06,74m).

The quotes of the Negro River are measured every day since September 1902 until today. This work is based on the years 1903 until 1999. The five highest flooding happened in: 1953 (29,69m), 1976 (29,61m), 1989 (29,42m), 1922 (29,35m) and 1909 (29,17m). The five lowest floding happened in: 1963 (13,65m), 1906 (14,20m), 1997 (14,34m), 1916 (14,42m) and 1926 (14,54m). The five smaller values of maximum quotas were em: 1926 (21,77m), 1912 (24,84m), 1992 (25,42m), 1964 (25,91m) and 1980 (26,00m) and the five of minimum quotas were in: 1926 (21,77m), 1912 (24,84m), 1992 (25,42m), 1964 (25,91m) and 1980 (26,00m). The five larger differences reached in a same year among the maximum and minimum quotas happened in: 1997 (14,62m), 1909 (14,13m), 1953 (12,62m), 1952 (12,44m) and 1916 (12,21m). And the smallest ones happened in: 1912 (05,45m), 1968 (06,10m), 1985 (06,53m), 1974, (06,62m) and 1986 (06,74m).