Cars are submerged in floodwater in an apartment complex in Ulsan on Wednesday.
According to the Korea Meteorological Administration on Wednesday, Chaba brought winds of up to 49 m/s in parts of Jeju Island, second only to typhoon Maemi in 2003 (51.1 m/s).
The Seogwipo area of Jeju saw a record 116.7 mm of rain an hour.
The southeastern port cities of Busan and Ulsan were hit by heavy winds of up to 28.3 m/s and 21.5 m/s.
Ulsan experienced 104.2 mm of rainfall an hour, a record for the city.
Downpours also soaked nearby Gyeongju, North Gyeongsang Province, which was hit hard by a recent earthquakes, with 280 mm of rain.
According to the KMA, Chaba was the most powerful typhoon ever to hit the Korean Peninsula in October.
Typhoons usually hit Korea in the summer but are seen in October only once in a decade.
The last typhoon that caused such extensive damage in October was in 2013, and one in October 1994 did not cause nearly as much damage.
Comment: Asian typhoons are becoming more frequent and intense researchers say