U.S. Fish and Wildlife Service Annual Hydrologic Condition Designation

The annual hydrologic condition is determined by the total annual flow at the gage near Grand Island, NE.

  • If the annual flow is above 1,140,265 , the year is classified as “wet."
  • If the annual flow is below 679,815 , the year is classified as “dry.”
  • If the annual flow falls between 679,815 and 1,140,265 , the year is classified as “normal”.

These thresholds were determined in the program document using annual flows at Grand Island from 1947-1994 with the highest 1/3 of years classified as “wet”, the lowest 1/4 of years classified as “dry”, and the remaining years classified as “normal”.

For more information, see these documents:

 

Year Condition
1942 Wet
1943 Normal
1944 Normal
1945 Normal
1946 Normal
1947 Normal
1948 Normal
1949 Wet
1950 Normal
1951 Wet
1952 Wet
1953 Dry
1954 Dry
1955 Dry
1956 Dry
1957 Dry
1958 Normal
1959 Dry
1960 Normal
1961 Dry
1962 Normal
1963 Dry
1964 Dry
1965 Wet
1966 Normal
1967 Normal
1968 Normal
1969 Normal
1970 Wet
1971 Wet
1972 Wet
1973 Wet
1974 Wet
1975 Normal
1976 Dry
1977 Normal
1978 Normal
1979 Normal
1980 Wet
1981 Dry
1982 Normal
1983 Wet
1984 Wet
1985 Wet
1986 Wet
1987 Wet
1988 Normal
1989 Normal
1990 Normal
1991 Dry
1992 Normal
1993 Wet
1994 Normal
1995 Wet
1996 Wet
1997 Wet
1998 Wet
1999 Wet
2000 Wet
2001 Normal
2002 Dry
2003 Dry
2004 Dry
2005 Dry
2006 Dry
2007 Normal
2008 Normal
2009 Normal
2010 Wet
2011 Wet
2012 Normal
2013 Normal
2014 Normal
2015 Wet
2016 Wet
2017 Wet
2018 Normal
2019 Wet