{"id":8564,"date":"2020-07-31T11:48:53","date_gmt":"2020-07-31T14:48:53","guid":{"rendered":"http:\/\/www.ericjorden.com\/blog\/?p=8564"},"modified":"2020-07-31T11:48:53","modified_gmt":"2020-07-31T14:48:53","slug":"why-the-surprise-about-the-mud-slide-in-bc","status":"publish","type":"post","link":"http:\/\/www.ericjorden.com\/blog\/2020\/07\/31\/why-the-surprise-about-the-mud-slide-in-bc\/","title":{"rendered":"Why the surprise about the mud slide in BC?"},"content":{"rendered":"<p>I was surprised that a house was built in the path of the mud slide in British Columbia early this month, July 4th.\u00a0 Built right in a mud channel.\u00a0 Particularly in view of the fact that the Ministry of Transport reported that more slides were possible &#8211; they knew. (Ref. 1) Why were houses approved for construction in such an unstable area?\u00a0 Who is liable?<\/p>\n<p>Assessing the potential for a mud slide in an area and quantifying the risk for residents is not rocket science.\u00a0 Someone had done sufficient assessment to warrant the report of the Ministry.<\/p>\n<p>You don&#8217;t see the messy stuff mentioned as such in engineering books but it&#8217;s there.\u00a0 It&#8217;s classified as <em>very soft clay and silt with a little sand and gravel and a few cobbles<\/em>.\u00a0 The analytical procedures are in the books too &#8211; reliable slope stability methods of analysis understood by experienced engineers.<\/p>\n<p>So, what&#8217;s the big surprise about the mess in BC and why were people allowed to build there?\u00a0 We&#8217;re not talking something small here.\u00a0 We&#8217;re talking about a slide that engulfed a house to a depth of several feet according to pictures on line.\u00a0 And moving fast too as seen in one video of a fellow running out of the way just in time.<\/p>\n<p>You don&#8217;t need a lot of data to do such an analysis either and the data is readily available in the public domain:<\/p>\n<ul>\n<li>The history of mud slides in the area and the rain fall at the time<\/li>\n<li>Topographic maps to give you the shape and slope of the ground, and the location of mud channels<\/li>\n<li>The results of terrain analysis identifying features relevant to mud slides, and evidence of past events (screen grabs from video taken from low flying drones has had a big impact on the engineering analysis of terrain in an area)<\/li>\n<li>Soil maps (<em>surficial geology<\/em> maps) to tell you that a mixture of clay and silt underlies the area<\/li>\n<\/ul>\n<p>Engineers have done this type of assessment often, and everywhere throughout North American and around the world.\u00a0 And based on the news and Transportation&#8217;s report, likely for this area as well.<\/p>\n<p>So why the surprise?<\/p>\n<p>Why would a person even mistakenly build a house in a mud channel?\u00a0 I can&#8217;t help but think there would be local knowledge that would kick in even if the government was silent.\u00a0 Would you build a house in a river channel or on a flood plain between wet seasons?<\/p>\n<p><strong>Reference<\/strong><\/p>\n<ol>\n<li>Notes taken from a CBC News report online.\u00a0 &#8220;Debris flood, a mix of mud, gravel and cobbles 200 km east of Prince George, BC in a flood prone area 1:30 Saturday morning July 4, 2020.\u00a0 Waist deep.\u00a0 Second one that day nearby.\u00a0 Ministry of Transport said more likely in the area&#8221;<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"<p>I was surprised that a house was built in the path of the mud slide in British Columbia early this month, July 4th.\u00a0 Built right in a mud channel.\u00a0 Particularly in view of the fact that the Ministry of Transport &hellip; <a href=\"http:\/\/www.ericjorden.com\/blog\/2020\/07\/31\/why-the-surprise-about-the-mud-slide-in-bc\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/www.ericjorden.com\/blog\/wp-json\/wp\/v2\/posts\/8564"}],"collection":[{"href":"http:\/\/www.ericjorden.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.ericjorden.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.ericjorden.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.ericjorden.com\/blog\/wp-json\/wp\/v2\/comments?post=8564"}],"version-history":[{"count":10,"href":"http:\/\/www.ericjorden.com\/blog\/wp-json\/wp\/v2\/posts\/8564\/revisions"}],"predecessor-version":[{"id":8619,"href":"http:\/\/www.ericjorden.com\/blog\/wp-json\/wp\/v2\/posts\/8564\/revisions\/8619"}],"wp:attachment":[{"href":"http:\/\/www.ericjorden.com\/blog\/wp-json\/wp\/v2\/media?parent=8564"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.ericjorden.com\/blog\/wp-json\/wp\/v2\/categories?post=8564"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.ericjorden.com\/blog\/wp-json\/wp\/v2\/tags?post=8564"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}