Flow alteration of streams from anthropogenic impacts is ubiquitous worldwide. In this paper we examine flow alteration in the Wabash River watershed. The Indicators of Hydrological Alteration software was used to evaluate hydrological variables generated from daily discharge during the past several decades at 80 USGS gauging stations. We used regressions of hydrological variables with time to identify hydrologic change. An average of 6.9 hydrologic variables (of 33 variables) were significantly altered at each station, and stations with larger watersheds had an increased number of altered variables. Streams with upstream dams had increased minimum flows for all but the 90-day minimum variable, decreased maximum flows for all increments, increased fall rate, decreased summer monthly flows, and decreased high pulse count. The presence of agriculture in upstream watersheds resulted in increased number of zero flow days, increased low pulse counts, and decreased high flows during October and April. No significant differences were detected in hydrologic alteration based on urban coverage in upstream watersheds. Although this study did not quantify ecological degradation, hydrologic alterations in the Wabash River watershed have undoubtedly resulted in ecological degradation.