{"id":16377,"date":"2015-10-05T08:20:59","date_gmt":"2015-10-05T08:20:59","guid":{"rendered":"http:\/\/blogs.agu.org\/landslideblog\/?p=16377"},"modified":"2015-10-05T08:20:59","modified_gmt":"2015-10-05T08:20:59","slug":"the-seismically-triggered-landslide-dam-in-honshiyan-yunnan-china-a-review-of-a-new-paper","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2015\/10\/05\/the-seismically-triggered-landslide-dam-in-honshiyan-yunnan-china-a-review-of-a-new-paper\/","title":{"rendered":"The seismically triggered landslide dam in Honshiyan, Yunnan, China: a review of a new paper"},"content":{"rendered":"<h5>The Honshiyan landslide dam in Yunnan, China<\/h5>\n<p>On 3rd August 2014 a Ms=6.5 earthquake in Ludian County, Yunnan Province in China <a href=\"https:\/\/blogs.agu.org\/landslideblog\/2014\/08\/06\/yunnan-earthquake-images-of-the-valley-blocking-landslides\/\">triggered a large landslide at Honshiyan<\/a>, about 1.5 km downstream of an existing hydroelectric power station.\u00a0 This landslide blocked the Niulanjiang River, requiring emergency actions to drain the lake impounded behind the dam.\u00a0 In a new paper just published online in the journal Landslides,<a href=\"http:\/\/link.springer.com\/article\/10.1007\/s10346-015-0639-5\"> Zhang <em>et al.<\/em> (2015)<\/a> examine both the emergency actions needed to mitigate the immediate threat and the potential for the use of the dam for hydroelectric power generation.<\/p>\n<h5>The emergency response to the Honshiyan landslide dam<\/h5>\n<p>Zhang <em>et al.<\/em> (2015) describe the parameters of the blockage &#8211; it had a volume of 12 million cubic metres, was 92 metres high, 753 metres wide and 283 metres long.\u00a0 However, the blockage was rather complex as it was formed from two different collapse events from each side of the valley, as shown in the images below from the paper:<\/p>\n<div id=\"attachment_16380\" style=\"width: 317px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2015\/10\/15_10-China-dam-1.gif\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-16380\" class=\"wp-image-16380 size-full\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2015\/10\/15_10-China-dam-1.gif\" alt=\"Hongshiyan landslide dam\" width=\"307\" height=\"205\" \/><\/a><p id=\"caption-attachment-16380\" class=\"wp-caption-text\">Panoramic view of the Hongshiyan landslide dam. This photo was taken upstream of the landslide dam (<a href=\"http:\/\/link.springer.com\/article\/10.1007\/s10346-015-0639-5\">Zhang et al. 2015<\/a>)<\/p><\/div>\n<p>.<\/p>\n<p>Analysis of the structure of the deposit suggested that it had a relatively high proportion of fine-grained particles as well as large boulders. Using a variety of analysis methods, <a href=\"http:\/\/link.springer.com\/article\/10.1007\/s10346-015-0639-5\">Zhang <em>et al.<\/em> (2015<\/a>) concluded that:<\/p>\n<blockquote><p>Based on the parameters of the Hongshiyan landslide dam and the field observations, the breaching risk of this landslide dam is located between the levels of \u201chigh risk\u201d and \u201clow risk\u201d. Both the quantitative and qualitative rapid assessment methods indicate that the Hongshiyan landslide dam should be considered unstable.<\/p><\/blockquote>\n<p>In response, the authorities initiated the construction of a spillway across the landslide dam on 10th August 2014.\u00a0 The channel, which was 30 m wide at the top and 5 m wide at the base, was completed 11 days later\u00a0 This successfully prevented a dam break event.\u00a0 Thereafter, whilst the paper is a little unclear, it appears that a new tunnel was drilled into the mountainside to link to the existing diversion tunnel for the Hongshiyan hydropower station, allowing complete drawdown of the lake, as shown in the image (from Zhang et al. 2015) below:<\/p>\n<h5><\/h5>\n<div id=\"attachment_16382\" style=\"width: 416px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2015\/10\/15_10-China-dam-2.gif\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-16382\" class=\"wp-image-16382 size-full\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2015\/10\/15_10-China-dam-2.gif\" alt=\"Hongshiyan landslide dam\" width=\"406\" height=\"270\" \/><\/a><p id=\"caption-attachment-16382\" class=\"wp-caption-text\">Water impounded in the dammed lake has been released by the new constructed channel. As shown in this picture taken on October 10th, the submerged artificial concrete dam has been exposed (from <a href=\"http:\/\/link.springer.com\/article\/10.1007\/s10346-015-0639-5\">Zhang <em>et al.<\/em> 2015<\/a>)<\/p><\/div>\n<p>.<\/p>\n<h5>The use of the Honshiyan landslide dam for hydroelectric power generation<\/h5>\n<p>Interesting, because of the existence of the diversion tunnel, the Honshiyan landslide dam has the potential to be used for hydroelectric power generation.\u00a0 <a href=\"http:\/\/link.springer.com\/article\/10.1007\/s10346-015-0639-5\">Zhang <\/a><a href=\"http:\/\/link.springer.com\/article\/10.1007\/s10346-015-0639-5\"><em>et al.<\/em><\/a><a href=\"http:\/\/link.springer.com\/article\/10.1007\/s10346-015-0639-5\"> (2015)<\/a> have suggested that at a cost of\u00a0 between 1\u00a0 billion and 1.5 billion RMB the landslide dam could be converted into a viable power generation site, generating a full return on investment in about four years. Thus, unusually, this landslide dam has the potential to generate long term economic benefits to the region.<\/p>\n<h5>Reference<\/h5>\n<p><span class=\"AuthorName_container\"><span class=\"AuthorName\">Zhang, S., <\/span><\/span><span class=\"AuthorName_container\"><span class=\"AuthorName_container\"><span class=\"AuthorName\">Xie, X., Wei, F., Chernomorets, S., Petrakov, D., Pavlova, I. and Tellez, R.D. 2015.\u00a0<a href=\"http:\/\/link.springer.com\/article\/10.1007\/s10346-015-0639-5\">A seismically triggered landslide dam in Honshiyan, Yunnan, China: from emergency management to hydropower potential<\/a>.\u00a0 <em>Landslides<\/em>, avalailble online 23rd Septeber 2015, 11 pages,<br \/>\n<\/span><\/span><\/span><\/p>\n<!-- AddThis Advanced Settings generic via filter on the_content --><!-- AddThis Share Buttons generic via filter on the_content -->","protected":false},"excerpt":{"rendered":"<p>In a just published paper, Zhang et al. 2015 describe the emergency works undertaken to mitigate the seismically triggered landslide dam at Honshiyan, Yunnan in China in 2014.<!-- AddThis Advanced Settings generic via filter on wp_trim_excerpt --><!-- AddThis Share Buttons generic via filter on wp_trim_excerpt --><\/p>\n","protected":false},"author":22,"featured_media":16380,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[537,3],"tags":[16,23,469,15,959,688,296],"class_list":["post-16377","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-earthquake-induced-landslide","category-landslide-report","tag-china","tag-earthquake","tag-featured","tag-landslide-dam","tag-landslide-report","tag-valley-blocking-landslide","tag-yunnan"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/16377","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/users\/22"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/comments?post=16377"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/16377\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/16380"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=16377"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=16377"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=16377"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}