{"id":17977,"date":"2016-03-14T07:00:30","date_gmt":"2016-03-14T07:00:30","guid":{"rendered":"http:\/\/blogs.agu.org\/landslideblog\/?p=17977"},"modified":"2016-03-12T08:45:55","modified_gmt":"2016-03-12T08:45:55","slug":"managing-urban-landslides-1","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2016\/03\/14\/managing-urban-landslides-1\/","title":{"rendered":"Managing urban landslides"},"content":{"rendered":"
Managing urban landslides<\/h5>\n

On my last day in Kalimpong<\/a>, Praful Rao of Save the Hills<\/a> took me to visit an area of comparatively low wealth below the main town.\u00a0 This area, called Dumsi Pakha, provides a sad case study of the way that urban development in steep terrains can lead to landslide problems, with catastrophic outcomes for the inhabitants.\u00a0 This image gives an overview of the settlement, with large numbers of small houses sitting on the side of the steep hill. The challenge of managing urban landslides in such settings is clear:<\/p>\n

\"Managing

Managing urban landslides: an overview of Dumsi Pakha<\/p><\/div>\n

.<\/p>\n

Landslides affect communities like this in multiple ways, but the two key elements that cause the problems are poor water management and slope disruption.\u00a0 As I noted in an earlier post in this sequence<\/a>, water management in the town on the slopes above is a key factor.\u00a0 In Kalimpong town, water is discharged without any control into gulleys than run through Dumsi Pakha.\u00a0 This is one of those gulleys:<\/p>\n

\"Managing

Managing urban landslides: a gully in Dumsi Pakha<\/p><\/div>\n

.<\/p>\n

The channel is of course dry towards the end of the dry season, and is choked with garbage.\u00a0 Note the extensive instability on the flanks of the channel in both the foreground and on the other side of the gully.\u00a0 This instability is being driven by the large flows that the channel now has to transport during the monsoon.\u00a0 These small landslides threaten many houses, whilst in some cases larger (but still not huge) slips are developing on the channel flanks.\u00a0 These have the potential to slip into the channel, briefly blocking it and then allowing a catastrophic debris flow to develop.<\/p>\n

But elsewhere in the settlement the problems are more local.\u00a0 This house for example seems to have been built by first creating a bench by excavating into the slope:<\/p>\n

\"Managing

Managing urban landslides: an unsupported cut slope in Dumsi Pakha<\/p><\/div>\n

.<\/p>\n

Note the boulders at the foot of the slope.\u00a0 This is a highly dangerous situation.\u00a0 It seems inevitable that this unsupported slope will, in time, collapse.\u00a0 There is a high chance that is in so doing it will cause severe damage to the house.<\/p>\n

And then in other places there are cases of old landslides that have been reactivated by humans.\u00a0 This is the community centre, which was completed in 2002.\u00a0 There are very obvious signs of movement:<\/p>\n

\"Managing

Managing urban landslides: the community centre at Dumsi Pakha<\/p><\/div>\n

.<\/p>\n

This deeper-seated movement is seen quite widely in Dumsi Pakha, although it is not ubiquitous.\u00a0 The clearest example is close to the community centre, where there is extensive movement occurring, bounded by the gully that I described above.\u00a0 The bridge across the gully is now extensively distorted, and the slope behind is moving quite extensively, as the steps behind Praful illustrate:<\/p>\n

\"Managing

Managing urban landslides: extensive movement due to reactivattion of existing landslides<\/p><\/div>\n

.<\/p>\n

I think it is very important not to give the impression that the people living in Dumsi Pakha are passive victims of these problems.\u00a0 In many cases they are trying to manage the risk – for example they have built this retaining wall to try to stabilise a section of the slope that is particularly hazardous:<\/p>\n

\"Managing

Managing urban landslides: a retaining wall constructed by local people<\/p><\/div>\n

.<\/p>\n

But the scale of the problems is so large that they cannot be solved alone.\u00a0 It is clear as to why people in these communities fear the monsoon so much; landslide accidents are inevitable in such settings without better management of the slopes. Dumsi Pakha is not exceptional or unusual – these types of problems are very commonplace.<\/p>\n","protected":false},"excerpt":{"rendered":"

On the last day of my visit to Kalimpong, Praful Rao took me to Dumsi Pakha, a poor hillside community with problems in managing urban landslides<\/p>\n","protected":false},"author":22,"featured_media":17989,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_members_access_role":[],"_members_access_error":""},"categories":[64],"tags":[469,5,1069,979,72,1071],"class_list":["post-17977","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-monsoon","tag-featured","tag-india","tag-kalimpong","tag-monsoon","tag-south-asia","tag-urban-landslides"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/17977","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=17977"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/17977\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/17989"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=17977"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=17977"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=17977"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}