The Panchiao-Hsinchuang waterworks, downstream from the Shihmen Reservoir, supplies water to over a million people in Panchiao, Hsinchuang and Shulin. But along the 16 kilometers of the Tahan River from the Shihmen Reservoir to the waterworks, there are the Shihmen, Tahsi and Yingko urban development areas, which have over 70,000 inhabitants, but no sewage treatment systems.
位在石門水庫下游的板新淨水廠，供應板橋、新莊、樹林等一百多萬人口用水，但由石門水庫到板新水廠十六公里的大漢溪沿岸，有石門、大溪、鶯歌都市計畫區，共七萬多的人口，卻沒有汙水下水道。