The flood control plan for greater Taipei, which was drawn up in 1969, focused on the Tamsui River and the lower reaches of Keelung River, Hsintien Stream, and Tahan Stream, where the land is low-lying and the population at its densest.
攤開大台北防洪計畫圖來看，基隆河、新店溪、大漢溪三河的下游，與它們共同匯成的淡水河沿岸，地勢卻相當低，而這些地方人口又密集，因此成為防洪計畫中的重點區域。