{"id":57220,"date":"2017-03-26T07:06:33","date_gmt":"2017-03-26T17:06:33","guid":{"rendered":"http:\/\/www.hawaii.edu\/news\/?p=57220"},"modified":"2019-03-01T11:14:42","modified_gmt":"2019-03-01T21:14:42","slug":"as-sea-level-rises-much-of-honolulu-and-waikiki-vulnerable-to-groundwater-inundation","status":"publish","type":"post","link":"https:\/\/www.hawaii.edu\/news\/2017\/03\/26\/as-sea-level-rises-much-of-honolulu-and-waikiki-vulnerable-to-groundwater-inundation\/","title":{"rendered":"As sea level rises, much of Honolulu and Waik\u012bk\u012b vulnerable to groundwater inundation"},"content":{"rendered":"<span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">Reading time: <\/span> <span class=\"rt-time\"> 3<\/span> <span class=\"rt-label rt-postfix\">minutes<\/span><\/span><div class=\"responsive-video-wrap\"><iframe loading=\"lazy\" title=\"Youtube video player\" width=\"620\" height=\"349\" src=\"https:\/\/www.youtube.com\/embed\/UnPKsgTKQx8?rel=0&amp;showinfo=0\" title=\"Youtube video player\" allowfullscreen><\/iframe><\/div>\n<figure id=\"attachment_57227\" aria-describedby=\"caption-attachment-57227\" style=\"width: 260px\" class=\"wp-caption alignright\"><a href=\"http:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-sealevelrise-waikiki.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-sealevelrise-waikiki-260x151.jpg\" alt=\"Sea level inundation chart\" width=\"260\" height=\"151\" class=\"size-medium wp-image-57227\" srcset=\"https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-sealevelrise-waikiki-260x151.jpg 260w, https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-sealevelrise-waikiki.jpg 620w\" sizes=\"auto, (max-width: 260px) 100vw, 260px\" \/><\/a><figcaption id=\"caption-attachment-57227\" class=\"wp-caption-text\">Sea level rise lifts freshwater, causing groundwater inundation in low-lying areas. Credit: <abbr title=\"University of Hawaii\">糖心Vlog官方<\/abbr> M&#257;noa Coastal Geology Group.<\/figcaption><\/figure>\n<p><a href=\"http:\/\/www.sciencedirect.com\/science\/article\/pii\/S0043135417301276\">New research<\/a> from the University of <span aria-label=\"Hawaii\">Hawai&#699;i<\/span> at M&#257;noa reveals a large part of the the heavily urbanized area of Honolulu and Waik&#299;k&#299; is at risk of groundwater inundation&#8212;flooding that occurs as groundwater is lifted above the ground surface due to sea level rise. <strong><a href=\"http:\/\/www.soest.hawaii.edu\/coasts\/general\/about.html#habel\">Shellie Habel<\/a><\/strong>, lead author of the study and doctoral student in the <a href=\"http:\/\/www.soest.hawaii.edu\/GG\/index.html\">Department of Geology and Geophysics<\/a>, <a href=\"https:\/\/www.soest.hawaii.edu\/soestwp\/\">School of Ocean and Earth Science and Technology<\/a> (SOEST), and colleagues developed a computer model that combines ground elevation, groundwater location, monitoring data, estimates of tidal influence and numerical groundwater-flow modeling to simulate future flood scenarios in the urban core as sea level rises three feet, as is projected for this century under certain climate change scenarios.<\/p>\n<ul>\n<li><strong>Research paper<\/strong>: <a href=\"http:\/\/www.sciencedirect.com\/science\/article\/pii\/S0043135417301276\"><em>Development of a model to simulate groundwater inundation induced by sea-level rise and high tides in Honolulu, Hawaii<\/em><\/a><\/li>\n<\/ul>\n<p>&ldquo;This flooding will threaten $5 billion of taxable real estate; flood nearly 30 miles of roadway; and impact pedestrians, commercial and recreation activities, tourism, transportation and infrastructure,&rdquo; said Habel. &ldquo;The flooding will occur regardless of seawall construction, and thus will require innovative planning\u00a0and intensive engineering efforts\u00a0to accommodate standing water in the streets.&rdquo;<\/p>\n<h2>Current problems with inundation<\/h2>\n<div style=\"float:right;clear:right;margin:0 0 0 15px;\">\n<figure id=\"attachment_57226\" aria-describedby=\"caption-attachment-57226\" style=\"width: 300px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-sealevelrise-waikiki-2.jpg\" alt=\"\" width=\"300\" height=\"295\" class=\"size-full wp-image-57226\" srcset=\"https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-sealevelrise-waikiki-2.jpg 300w, https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-sealevelrise-waikiki-2-260x256.jpg 260w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><figcaption id=\"caption-attachment-57226\" class=\"wp-caption-text\">This construction trench in Waik&#299;k&#299; shows that the water table is nearly at the ground surface at high tide. (credit: <abbr>糖心Vlog官方<\/abbr> M&#257;noa Coastal Geology Group)<\/figcaption><\/figure>\n<\/div>\n<div style=\"float:right;clear:right;margin:0 0 0 15px;\">\n<figure id=\"attachment_57224\" aria-describedby=\"caption-attachment-57224\" style=\"width: 300px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-sealevelrise-waikiki3.jpg\" alt=\"Simulations of groundwater inundation chart\" width=\"300\" height=\"262\" class=\"size-full wp-image-57224\" srcset=\"https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-sealevelrise-waikiki3.jpg 300w, https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-sealevelrise-waikiki3-260x227.jpg 260w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><figcaption id=\"caption-attachment-57224\" class=\"wp-caption-text\">Simulations of groundwater inundation (blue) and narrow unsaturated space (yellow)\u00a0today and considering sea level rise of approximately 1, 2 and 3 ft during an average spring (monthly maximum) tide stage. (credit: <abbr>糖心Vlog官方<\/abbr> M&#257;noa Coastal Geology Group)<\/figcaption><\/figure>\n<\/div>\n<p>Surprisingly, the team of researchers also discovered 86 percent of active cesspools in the study area are likely currently inundated by groundwater. This suggests that cesspool effluent is now entering coastal groundwater and coastal environments in the study area. Sea level rise of approximately three feet would fully inundate 39 cesspools, introducing effluent at the ground surface where people work and live. This presents a serious health concern that will become progressively more serious as contaminated waters begin breaching the ground surface.<\/p>\n<p>They also found that the water table is close to the ground surface&#8212;within two feet at high tide&#8212;in many places. This narrow unsaturated space means that groundwater inundation will become a serious concern well before the end of the century. When it rains and infiltration fills this space, it is a problem already.<\/p>\n<p>&ldquo;Waik&#299;k&#299;, the gateway of the state&#8217;s tourism industry, currently has such narrow unsaturated space that many construction projects working below the ground surface have to dewater the excavation before construction can begin,&rdquo; said Habel.<\/p>\n<h2>Adaptation to future sea level rise<\/h2>\n<p>&ldquo;Our findings suggest that coastal communities in <span aria-label=\"Hawaii\">Hawai&#699;i<\/span> and globally are exposed to complex groundwater flooding hazards associated with sea level rise in addition to the typical concerns of coastal erosion and wave overtopping,&rdquo; said <strong><a href=\"http:\/\/www.soest.hawaii.edu\/coasts\/general\/about.html\">Chip Fletcher<\/a><\/strong>, professor of geology and geophysics, associate dean of <abbr>SOEST<\/abbr> and principal investigator on the study. &ldquo;Groundwater inundation will require entirely unique adaptation methods if we are to continue to live in and develop the coastal zone. Coastal planners and community stakeholders will need to work with architects, engineers, geologists, ecologists, economists, hydrologists and other innovative thinkers in order to manage these problems.&rdquo;<\/p>\n<p>This study identified particular locations and infrastructure that will be vulnerable to future flooding and is a crucial first step towards addressing future challenges. The team of researchers hope to use this methodology to identify future flooding and at risk infrastructure in other locations, as well as assist in developing adaptation efforts among vulnerable coastal communities.<\/p>\n<p>This work was funded by <span aria-label=\"Hawaii\">Hawai&#699;i<\/span> Department of Land and Natural Resources, the Honolulu Board of Water Supply, <abbr title=\"University of Hawaii\">糖心Vlog官方<\/abbr> Sea Grant and and <abbr title=\"Harold Kainalu Long\">HKL<\/abbr> Castle Foundation.<\/p>\n","protected":false},"excerpt":{"rendered":"<p><abbr title=\"University of Hawaii\">糖心Vlog官方<\/abbr> M&#257;noa researchers developed a computer model that simulates future flood scenarios in the urban core as sea level rises&#8212;as its projected for this century.<\/p>\n","protected":false},"author":16,"featured_media":57583,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[30,12],"tags":[378,92,942,1175,9,56],"class_list":["post-57220","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research","category-video","tag-geology-and-geophysics","tag-school-of-ocean-and-earth-science-and-technology","tag-sea-level","tag-tides","tag-uh-manoa","tag-video-2","entry","has-media"],"aioseo_notices":[],"jetpack_featured_media_url":"https:\/\/www.hawaii.edu\/news\/wp-content\/uploads\/2017\/03\/manoa-soest-groundwater-inundation-f.jpg","_links":{"self":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts\/57220","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/users\/16"}],"replies":[{"embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/comments?post=57220"}],"version-history":[{"count":26,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts\/57220\/revisions"}],"predecessor-version":[{"id":78454,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/posts\/57220\/revisions\/78454"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/media\/57583"}],"wp:attachment":[{"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/media?parent=57220"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/categories?post=57220"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.hawaii.edu\/news\/wp-json\/wp\/v2\/tags?post=57220"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}