The Feitsui reservoir is the drinking water source for the Taipei metropolis, and nonpoint source pollution in this reservoir has been considered as an important issue. Buffer Strips are one of the best management practices (BMPs) and are used in Feitsui reservoir management. In this study, we integrate geographic information systems (GIS) and Stormwater Management Model (SWMM) to assess the effects of buffer strips in Feitsui reservoir.The major water quality items contain suspended solids (SS), total phosphorus (TP) and biochemical oxygen demand (BOD). The results show placing buffer strips 50 m in width around the reservoir can reduce 80% of SS, 50% of TP,and 70% of COD for the subwatersheds with buffer strips. In addition, the Vollenweider model is utilized to assess water quality in the reservoir and the results show that a 19-22% pollution reduction rate is required to achieve the goal of 10μg/L of TP. Buffer strips 50m in width contributed 1/3-1/4 reduction loads, which is 800 kgTP/yr. In addition to buffer strips, more BMPs are necessary in the watershed management of Feitsui reservoir.
Key Words : Buffer strips, SWMM, Vollenweider model, Nonpoint Source Pollution.