Abstract: Low-flow characteristics of Wisconsin streams at 415 sewage-treatment plants are presented in this report. The low-flow characteristics presented are the annual minimum 7-day mean flow that occurs on the average of once in 2 years and the annual minimum 7-day mean flow that occurs on the average of once in 10 years. The low-flow characteristics at most sewage-treatment plants were determined by correlating baseflow measurements at the sewage-treatment plants to the concurrent daily mean flow at continuous-record gaging stations in the area. The accuracy determined by the standard error of estimate for the 10-year low flow ranged from 18 percent at continuous-record gaging stations to 70 percent when only three base-flow measurements were available. The standard error of 70 percent is larger than anticipated when the project was initiated. This was the result of extremely poor base-flow conditions during the 2-year data collection period. Additional base-flow conditions will be obtained during subsequent years which will improve the standard error somewhere between 29 and 45 percent.