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AcknowledgmentsThe authors would like to recognize Robert Jarrett, formerly of the U.S. Geological Survey (USGS), who was instrumental in helping develop the concept for this study and a plan to execute it. Julie Kiang of the USGS offered invaluable technical assistance during the undertaking of the study. Graph showing relation between 1-percent annual exceedance-probability discharges computed from the peak-streamflow regional-regression equations in the Foothills and Plains hydrologic regions of Colorado and the 1-percent annual exceedance-probability discharges computed from the peak-streamflow regional-regression equations in Capesius and Stephens (2009)
Conversion FactorsInch/Pound to International System of Units Elevation, as used in this report, refers to distance above the vertical datum.Water year in this report is defined as the period from October 1st of one year through September 30th of the following year and is named for the year of the ending date. equations and when eastern Colorado was divided into two separate hydrologic regions. To make further reductions in the uncertainties of the peak-streamflow regional-regression equations in the Foothills and Plains hydrologic regions, additional streamgages or crest-stage gages are needed to collect peakstreamflow data on natural streams in eastern Colorado. Generalized-Least Squares regression was used to compute the final peak-streamflow regional-regression equations for peakstreamflow. Dividing eastern Colorado into two new individual regions at -104° longitude resulted in peak-streamflow regionalregression equations with the smallest SEP. The new hydrologic region located between -104° longitude and the Kansas-Nebraska State line will be designated the Plains hydrologic region and the hydrologic region comprising the rest of eastern Colorado located west of the -104° longitude and east of the Rocky Mountains and below 7,500 feet in the South Platte River Basin and below 9,000 feet in the Arkan...