Da-an River

Da'an River
Da'an River in Taiwan
Country	Taiwan
Basin features
Main source	Xueshan Range: Dabajian Mountain 3,488 m (11,444 ft)
River mouth	Taiwan Strait 24°24′26″N 120°35′35″E / 24.4072°N 120.5931°E / 24.4072; 120.5931Coordinates: 24°24′26″N 120°35′35″E / 24.4072°N 120.5931°E / 24.4072; 120.5931
Basin size	758.47 km2 (292.85 sq mi)
Physical characteristics
Length	95.76 km (59.50 mi)
Discharge	Maximum rate: 13,840 m3/s (489,000 cu ft/s)

The Da'an River (Chinese: 大安溪; pinyin: Dà'ān Xī) is a river in northwestern Taiwan. It flows through Miaoli County and Taichung City for 96 kilometres (60 mi). It reaches the Taiwan Strait between the Dajia District and Da'an District, Taichung.

The Da'an River was affected by the "921 earthquake" in 1999, where a gorge was formed (called Da'an River Grand Canyon Chinese: 大安溪大峽谷). In some of the fastest erosion geologists have ever seen, the gorge is being eaten away from its upstream end at a rate of 17 meters per year. They expect the gorge to be erased after 50 years.