150,000 next to danger slopes

PUBLISHED : Thursday, 30 March, 2000, 12:00am
UPDATED : Thursday, 30 March, 2000, 12:00am

More than 150,000 people are living in public housing blocks next to slopes as dangerous as one in Shekkipmei which collapsed in August, a report disclosed yesterday.


Eleven slopes near nine government estates of similar age and design to the Shekkipmei one are singled out in the Landslip Preventive Measures Programme.


This follows the results of a probe into the Shekkipmei landslip which said a combination of factors, including lack of maintenance, caused a sudden rise in the ground water level on August 25.


The nine estates are: Kwai Shing East, Kwai Shing West, Tai Wo Hau and Lai King in Kwai Chung; Hin Keng in Sha Tin; Shekkipmei, Pak Tin, and So Uk in Shamshuipo; and Fung Wah in Chai Wan.


A spokesman for the Housing Department said the slopes had been included in an upgrading programme by the Geotechnical Engineering Office but there was no need to relocate residents.


'Some of the slopes lie outside the area of the estates and do not create any immediate threat,' the spokesman said.


'Limited work may be carried out by the office but, if so, there still appears to be no such need to relocate residents.' Office chief Raymond Chan Kin-shek said the 11 slopes, now listed as priorities, would be studied in detail and reinforced within two years.


Professor John Burland, from London University, appointed to lead the investigation, said the factors leading to the rise in water level at Shekkipmei included direct infiltration after unauthorised cultivation of 1,000 square metres of land, cracks on slope surfaces, and sudden torrential rainfall and ground water flow during Typhoon Sam.


The rise in ground water reduced the 'suction' force within the slope leading to its movement, which was further increased by built-in weakness of the slope.


Professor Burland said the slope had not been inspected by the Government since 1993.


Assistant Secretary for Works Mak Ka-wai admitted maintenance responsibilities for public slopes had not been clearly defined until a system was introduced last year.


Now there were clear-cut responsibilities covering all 54,000 man-made slopes in Hong Kong, he said.


No one was killed in the landslide at Shekkipmei, but 700 elderly people were evacuated and later resettled in other government housing as blocks near the slide were deemed unsafe.