Report No. : GEO Report No. 291

Report Title : Review of The 21 August 2005 Landslide Incident on Slopes at The Shing Mun Catchwater Tso Kung Tam Tsuen Wan (2013), 68 p.

Author : Halcrow China Limited

Abstract

This report presents the review findings of a landslide (Incident No. 2005/08/0391) which occurred on slopes Nos. 6SE-B/CR193 and 6SE-B/CR212 above the Shing Mun Catchwater between chainage 7010 and chainage 7050, Tso Kung Tam, Tsuen Wan on 21 August 2005. The landslide debris blocked the open catchwater channel below, resulting in overbank flow and subsequent washout failure of fill slope No. 6SE-B/F69 on the downhill side of the catchwater. Extensive washout failures also occurred on slope No. 6SE-B/DT15 adjoining the fill slope. The total volume of failures was more than 1,000 m³. As a result of the incident, a 15 m long section of the catchwater collapsed and an adjacent concrete access road at the crest of slopes Nos. 6SE-B/F69 and 6SE-B/DT15 was also undermined. No casualties were reported.

The key objectives of this review were to document the facts about the incident and to present relevant background information and pertinent site observations made under this review. The scope of the review does not include any ground investigation or detailed diagnosis of the causes of the incident. Recommendations for follow-up actions are reported separately.

Download Document(s)