Estimating generalized flood skew coefficients for Michigan

Current estimates of station skew indicate that estimates of generalized skew obtained from the skew map of the United States prepared by the U.S. Water Resources Council have a -0.27 bias for Michigan. Station skew was recomputed using currently recommended statistical procedures of the Water Resources Council, and available data through 1982. Generalized skew is combined with station skew in order to improve estimates of flood-flow frequencies. As a result of this study, the mean station skew for each of three designated regions can be used to estimate generalized skew in Michigan. The Upper Peninsula has a skew of 0.12; the southwest part of the Lower Peninsula has a skew of 0.081; the remainder of the Lower Peninsula has a skew of -0.17. The mean-square error associated with generalized skew determined on the basis of designated regions is 0.2.