Sijhih

The 106-kilometer section between Hsinchu and Sijhih of this new 11 7-kilometer freeway was opened to traffic in 1997, and the entire line was completed in 1999.

Source: wiktionary

By all accounts, the system worked as planned and the cities of Wudu and Sijhih were spared significant flooding as a result.

Source: wiktionary

On July 18th, 2000, a heavy rainfall occurred in the upstream watershed of Pachang Creek and induced a rapidly huge flow peak. Unfortunately, 4 professional hydraulic workers were flushed away. Three months later, Sijhih was inundated again by Typhoon Xangsane and nearly 2/3 of the urban area was flooded. Respectively, Cidu District and Nuannuan District in Keelung City suffered catastrophic floods, which caused 64 casualties, 65 injured, 25 disappearance and inestimable loss of agriculture, fishery and property.

Source: wiktionary

That programme, begun in the early 1990s, cost billions of Taiwan dollars, but eventually tamed the river, especially because of the Yuanshanzih flood diversion tunnel (sluiceway), which helps redirect run-off from the upper reaches of the river to the sea on the north-east coast, thus saving the often flooded townships of Rueifang and Hsichih (Sijhih)⁷ when future typhoons and heavy rains hit the area.

Source: wiktionary