Trout Unlimited’s Conservation Hydrology team (formerly CEMAR), has been studying the relationships between streamflow conditions and human water use in five project watersheds in Sonoma County since 2010. In the first few years of our work, we investigated the magnitudes, timing, and frequency of high and lows flows in each project watershed to characterize the flow regime of each stream. In more recent years, TU’s work has focused on studying low flow conditions during the summer dry season, to investigate the impacts of the recent drought and how water management practices influence streamflow conditions. Additionally, TU streamflow data is used by our partners to study the timing of significant biological thresholds, such as pool connectivity and over-summer survival.