The uneven distribution of water resources in Taiwan is due to severe topography change and unevenly distributed rainfall. Recently, climate change has resulted more apparent wet and dry seasons in the region. Because water deficit problems are more severe in the dry season, which is in the low flow period, groundwater is the main source of recharging streams. Thus, knowing the relationship between groundwater and stream drainage-storage is becoming increasingly important. This study establishes a recession curve to show the relationship between
streamflow and groundwater storage-drainage. The advantage of low flow analysis is that it only requires streamflow data. We exclude precipitation and evapotranspiration in low flow analysis that is only related to river basin water.Thus, the recession curve is characterized to display basin drainage behavior. In this study, we use southern Taiwan streamflow data covering a long-term period to analyze basin characteristics. The differences of drainage behaviors are compared using the Vogel & Kroll (1992) and Brutsaert (2008) methods. Furthermore, the groundwater storage in the south of Taiwan is quantified. The results show that Chaozhou station in the Donggang River Basin has a significantly
decreasing trend. Chaozhou station should implement precautionary measures.
Key Words : Streamflow, low flow, recession curve, storage.