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Slide 2 of 3

The methodology utilized to determine the average, wet and dry years involves plotting the average annual flows for the three earmarked gages previously discussed (Gages 11500, 20300 and 39500) for the period of record from 1971 to 1998. The 20th percentile is proposed to be used as the cutoff for identification of the wet and dry years. This means that five years have been initially identified as dry years and five years have been initially identified as wet years.

Based on the data, there were three consistently wet and dry years that stood out in both the upper and lower regions (1977, 1992 and 1994 for the dry years and 1983, 1984 and 1986 for the wet years). In summary the preliminary chosen wet and dry years are indicated below and on the chart

		Wet:	1972		Dry:	1977
			1983			1979
			1984			1990
	 		1986			1992
			1995			1994