14 March 2019
Losses from landslides in South Korea
South Korea is a nation that at times has suffered significant losses from landslides. The map below shows fatal landslides in the region from 2004 to 2018, as documented in Froude and Petley (2018) and mapped using our online mapping tool:-
In a new paper in the journal Engineering Geology, my friends Su-Gon Lee and Mike Winter have documented loss inducing landslides in South Korea from 1970 to 2018 (Lee and Winter 2019). This is a very useful paper that carefully explains the context of landslides in South Korea (strongly seasonal rainfall, high erosion rates, dense human occupation, etc.). The have counted a total of 1728 fatalities from landslides in the period between 1970 and 2018, a total that was higher than I expected. The paper provides the following really interesting graph of these losses with time:-
Overall there is a good news story here in that the graph clearly shows a decreasing trend in losses with time, which Lee and Winter (2018) attribute to better landslide management:-
“This trend may be attributed to the fact that the government of the Republic of Korea has paid more attention to, and expended greater financial resource on, the safety of infrastructure, particularly that pertaining to transport, including landslide mitigation as GDP has increased and the country has become wealthier.”
The dreadful 2011 debris flows in Seoul stand to remind us that we can never be complacent though – the 58 fatalities that occurred in those events were clearly a significant shock. The authors also describe the non-fatal effects of landslides, noting that the estimated annual property damage is in the range of US$500 million to US$1 billion. Landslides are a problem along transportation infrastructure in particular.
The image above, which I took when in South Korea with Su-Gon in 2007, nicely illustrates the problems posed by landslides in South Korea, and the mitigation measures needed to keep the population safe.
Froude, M. J. and Petley, D. N. 2018. Global fatal landslide occurrence from 2004 to 2016. Natural Hazards and Earth System Sciences, 18, 2161-2181, https://doi.org/10.5194/nhess-18-2161-2018.
Lee, S-G. and Winter, M.G. 2019. The effects of debris flow in the Republic of Korea and some issues for successful risk reduction. Engineering Geology, 251, 172-189. https://doi.org/10.1016/j.enggeo.2019.01.003