Low-flow characteristics of streams in the Pecatonica-Sugar River basin, Wisconsin
The purpose of this report is to describe low-flow characteristics of streams in the Pecatonica-Sugar River basin, Wisconsin, where streamflow data have been collected, and to present equations for estimating low-flow characteristics at ungaged sites. Low-flow characteristics were estimated for 11 gaging stations, 25 low-flow partial-record stations, and 207 miscellaneous sites in the basin. Estimates of flow duration were made at the 11 gaging stations. Also, low-flow discharge measurements are listed for 16 miscellaneous sites where insufficient data were available to estimate low-flow characteristics. Four equations are provided to estimate low-flow characteristics at ungaged sites and at sites where one base-flow discharge measurement is available. The equations were determined from multiple-regression analyses that related low-flow characteristics at gaging stations and partial-record stations to basin characteristics. Drainage area and base-flow index were the most significant parameters for these analyses. The standard error of estimate of the 7-day, 10-year low flow was provided. The average SE-j f iQ in the basin ranged from 10 to 64 percent and was dependent on the amount of low-flow data available.