A review of landslide problems and mitigation measures in Chongqing and Hong Kong:

Abstract

The cities of Chongqing and Hong Kong are both located at hilly areas which are highly populated, with buildings and major highways located very close to slopes and earth-retaining structures. Landslides and rockfalls are very common in both cities, and large expenditures are being incurred by both Governments on the investigation, design and implementation of mitigation and preventive measures to reduce the likelihood of the loss of life and economic losses due to landslides. As a result of the collaborative studies and technical exchange programs between the University of Hong Kong and the Chongqing Jianzhu University (), a more in-depth understanding of the landslide problem, methodology and mitigation measures in Chongqing and Hong Kong was achieved. The objective of this paper is therefore to: (1) highlight the similarities and differences of the slope safety problems which these cities have been facing and (2) present and compare the key technical approaches these two cities have been undertaken to reduce the risk of landslide and rockfalls, so that both cities could benefit from the experience and lesson learnt. Based on the review of literature and published case records, it is concluded that the city of Chongqing has to deal with natural hazards such as earthquake, river erosion and flooding more than that in Hong Kong, but both cities have been applying practical and latest technology to mitigating the landslide problem. It is recommended that the city of Chongqing should consider establishing a sustainable long-term landslide management plan and that the landslide prevention system being used in Hong Kong could be a good reference starting point.

Pre-, co-, and post- rockslide analysis with ALOS/PALSAR imagery: a case study of the Jiweishan rockslide, China

“…Rockslide is the movement of a mass of rock, debris, or earth down a slope under the influence of gravity (Cruden and Varnes, 1996). Rockslide failures have resulted in enormous casualties and huge economic losses in mountainous regions (Kwong et al, 2004;Parker et al, 2011;Xu et al, 2010). In recent years, many different mapping techniques have been implemented to study rockslide inventories, deformation monitoring, hazard, vulnerability assessments (Parise, 2001) and even post-event surface damage.…”

Identifying landslide activity as a function of economic development: a case study of increased landslide frequency surrounding Dominical, Costa Rica

“…However, monitoring of forest health, fragmentation, clearance and land conversion is often cited as a need which emphasizes the value of current and accurate data to create better early warning of the risk of landslide events (Kwong et al 2004;Spiker and Gori 2003). The seminal work for monitoring regional and global forest health and resources conducted by Fuller (2006) argues that monitoring is best done with large scale resolution (30 m and larger pixel size) imagery due to cost and time considerations, not to mention the confusion that results from too much information from high resolution/small scale images (15 m and smaller pixel size) can provide.…”

“…Costs for landslide clean-up are continually rising with estimates regularly hitting levels in the hundreds of millions to a few billion dollars in damages every year worldwide (Spiker and Gori 2003;Dai et al 2002). Mitigation techniques to prevent landslides, particularly in the developing world, rely upon better monitoring, restricting development in hazardous locations, better construction practices, and early warning systems (Kwong et al 2004;Spiker and Gori 2003;Dai et al 2002).…”

Landslides in Vitsi (Florina) Territory

“…On the other hand, extensive and simultaneous debris flows occurred after >300 mm in a 24 hour rainfall or >600 mm of continuous three-day rainfall (Froehlich et al, 1990;Froehlich and Starkel, 1993). Based on Kwong et al (2004) observation, an intense surface erosion is expected for slopes with rainfall intensity>50 mm/day.…”