Report No. : GEO Report No. 216

Report Title : Review of the 21 August 2005 Landslide on Slopes Nos. 7SE-B/C195 and 7SE-B/C131 and the Distressed Hillside above Slope No. 7SE-B/C122 at Ma On Shan Upper Village (2007), 79 p.

Author : Maunsell Geotechnical Services Limited

Abstract

This report presents the findings of a review of a landslide (Incident No. 2005/08/0384) that occurred on 21 August 2005 at Ma On Shan Upper Village. The landslide occurred on cut slopes Nos. 7SE-B/C195 and 7SE-B/C131, which were separated by a large drainage ditch. The detached debris (with a volume of about 1,000 m³) severely damaged three registered squatter structures and partly buried another registered squatter structure and resulted in the permanent evacuation and clearance of a number of other adjacent registered squatter structures. No casualties were reported as a result of the incident.

An adjacent area on and above slope No. 7SE-B/C122 was observed to have significant signs of distress in the form of numerous tension cracks and a recent toe slump failure (with a total volume of about 5000 m³). The observed distress and the toe slumping were noted to be recent and were probably concurrent with the landslide in August 2005. The total detached and displaced volume of the August 2005 landslide and the adjacent distressed hillside was about 6,000 m³.

Download Document(s)