A gaping hole appeared overnight in downtown Kaohsiung after one of the city's rapid transit construction sites caved in, bringing traffic gridlock to one of the most congested parts of town.
The cavity off of Chungcheng Road near the "Cultural Center" station - the No. 7 station on the Orange Line - had widened to a 10-meter deep 50 x 30 meter pit yesterday afternoon after the area had experienced four separate cave-ins in the previous 20 hours.
According to Fan Chen-bou, the chief executive officer of the Kaohsiung Rapid Transit Corp., workers were excavating earth to build a tunnel at the site Sunday afternoon at 5 p.m. when the tunneling bore hit a retention pond. Water sprung up, and a section of the tunnel measuring about 100 meters was ruptured by the force of the water.
After four hours of emergency attempts to fill the opening, the Chungcheng Road pavement gave in to the overwhelming water pressure.
Local media reported residents in the neighborhood said they had experienced a huge thud late Sunday night and thought it was an earthquake.
When the emerged from their homes yesterday morning, they were greeted by a 20-centimeter hollow on Chungcheng Road and a 600 square-meter pool of water in an adjacent park.
Sources said that over 200 KRTC workers were hauled out of bed early yesterday morning and worked nonstop for over twelve hours pouring gravel and soil into the hole.
Early efforts failed to prevent the spread of the destructive water flow. A third small case of subsidence occurred in the morning, and the big collapse that occurred in the park was where the pool of water came in earlier yesterday afternoon.
KRTC later announced that the situation had finally been brought under control.
"Over 7,000 cubic meters of soil and gravel has been poured into the opening, and has effectively kept the disaster from getting worse," Fan said.
Observers found the cavity in the park near the Chungcheng Road and Kaishuan Road intersection to be particularly frightening because it looked as though a big earthquake had struck, with part of the road gone and trees and streetlights toppled over.
Fan stated that Chungcheng Road would need to be cordoned off for seven to 10 days for safety concerns because of the accident.
He asserted that human error was not a factor in the accident, as the KTRC had done a geotechnical survey of the site before starting the work and concluded that the digging would not affect the retention pond.
The KRTC estimates it will take NT$500 million to rebuild the site.
This latest mishap is believed to be the eighth major accident of the Kaohsiung rapid transit railway project that has affected public safety. In 2004, the director of the Department of Rapid Transit System under the Kaohsiung city government resigned to take responsibility for a series of accidents.