On October 11, 2016, the functionality for Alaska StreamStats was expanded to include the ability to estimate the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual peak-flow exceedance probability discharges using regression equations from the report:

• Curran, J.H., Barth, N.A., Veilleux, A.G., and Ourso, R.T., 2016, Estimating flood magnitude and frequency at gaged and ungaged sites on streams in Alaska and conterminous basins in Canada, based on data through water year 2012: U.S. Geological Survey Scientific Investigations Report 2016-5024, 47 p.

In addition to presentation of the regression equations, the report also describes the errors associated with the estimates obtained from the equations, the methods used to develop the equations, and the methods used to compute the basin characteristics used as explanatory variables in the equations. StreamStats users should familiarize themselves with the report before attempting to obtain estimates of streamflow statistics for ungaged sites. Application of the equations to ungaged sites assumes that flows at the sites occur under natural conditions.