Tropical Storm Typhoon Chanchu formed in the western Pacific on May 8, 2006, roughly 500 miles east of the Philippines. The storm gradually built strength and size, reaching typhoon strength by May 11. It lost some strength as it crossed the Philippines, but once clear of the islands, it regained power and became a typhoon once again as it continued westward across the South China Sea.
While moving slowly through the South China Sea, Chanchu produced strong waves that struck the east coast of Vietnam. The associated flooding washed away many shrimp from coastal ponds and also entered Thu Bồn River, thus preventing its use as a source for irrigation for about 1,000 ha (2,500 acres) of rice paddy fields. Due to its unexpected change in course and ferocity, Chanchu caught dozens of ships off guard and damaged communications, sinking 17 ships and damaging several