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<html> <head><script type="text/javascript" src="/_static/js/bundle-playback.js?v=HxkREWBo" charset="utf-8"></script> <script type="text/javascript" src="/_static/js/wombat.js?v=txqj7nKC" charset="utf-8"></script> <script>window.RufflePlayer=window.RufflePlayer||{};window.RufflePlayer.config={"autoplay":"on","unmuteOverlay":"hidden"};</script> <script type="text/javascript" src="/_static/js/ruffle/ruffle.js"></script> <script type="text/javascript"> __wm.init("https://web.archive.org/web"); __wm.wombat("http://vulcan.wr.usgs.gov/Volcanoes/Rainier/Publications/debris_flow_maps.html","20100627181556","https://web.archive.org/","web","/_static/", "1277662556"); </script> <link rel="stylesheet" type="text/css" href="/_static/css/banner-styles.css?v=S1zqJCYt" /> <link rel="stylesheet" type="text/css" href="/_static/css/iconochive.css?v=3PDvdIFv" />  <title>CVO Website - Mount Rainier Debris-Flow Maps Available</title> </head> <body bgcolor="#ffffff" background="https://web.archive.org/web/20100627181556im_/http://vulcan.wr.usgs.gov/Imgs/Gif/Backgrounds/cvo_bkg.gif"> <a href="https://web.archive.org/web/20100627181556/http://www.usgs.gov/" target="_top"> <img border="0" alt="USGS/CVO Logo, click to link to National USGS Website" src="https://web.archive.org/web/20100627181556im_/http://vulcan.wr.usgs.gov/Imgs/Gif/logo2.gif"></a> <br> <a href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/" target="_top"> <i> USGS/Cascades Volcano Observatory, Vancouver, Washington </i></a> <hr> <h1>PRESS RELEASE: <br> Mount Rainier Debris-Flow Maps available from USGS </h1> <hr> <table border="0" cellpadding="10" width="100%"> <tr> <td> <b> United States Department of the Interior <br>Geological Survey, Western Region <br>Menlo Park, California 94025 <br>Public Affairs Office </b> <br> <br> <br> The maps and reports that describe the paths of potential large debris flows from the slopes of Mount Rainier are now available from U.S. Geological Survey. <p> "We are pleased to report that the maps and report that every one's been hearing about in the news are available at a nominal cost from USGS outlets and can be ordered over the telephone," according to the lead author, Dr. Kevin Scott of the USGS/Cascades Volcano Observatory in Vancouver, Washington. <p> The first report, <a href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Volcanoes/Rainier/Publications/HA-729/framework.html"> <b>"Debris Flow, Debris Avalanche, and Flood Hazards At and Downstream from Mount Rainier,"</b></a> consists of maps showing potential areas and probabilities of inundation, and was published as <b>"USGS Hydrologic Investigations Atlas 729,"</b> by K.M. Scott and J.W. Vallance. The cost is $6.25. The second report, <b>"Sedimentology, Behavior, and Hazards of Debris Flows at Mount Rainier,"</b> documents the scientific investigations of lahars from the volcano, and was published as <a href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Volcanoes/Rainier/Publications/PP1547/framework.html"> <b>"USGS Professional Paper (PP) 1547"</b></a>, by K.M. Scott, J.W. Vallance, and P.T. Pringle. The cost of this report is $8.50. <p> Copies of both reports are available from the USGS Branch of Distribution, Box 25425, Denver, CO 80225. Orders must specify the name and number of the report and include a check or money order payable to "Department of the Interior-USGS". Copies also are available over-the-counter or by mail from the USGS Earth Science Information Center (ESIC) at 904 West Riverside Avenue in Spokane, Washington. Office hours are 8:00 a.m. to 4:00 p.m., Monday through Friday. Mail orders may be placed by calling the Spokane ESIC at (509) 353-2524; or faxing the order to (509) 353-2872. <p> The two USGS studies define the statistical probability of inundation by volcanic debris flows (lahars) in five river valleys below the volcano. These debris flows are comprised of a rock-and-water slurry that looks and behaves like flowing concrete, according to Scott. "The destructive force of these flows moving at between 25 and 50 miles per hour is enormous," the USGS scientist said. "A debris flow similar to the type that could roar down the slopes of Mt. Rainier killed more than 23,000 people in Colombia (South America) in 1985." <p> Scott compared the risk of damage by a lahar at Mount Rainier with the risks of fire. "A home built in any of the probabilistically defined inundation areas on the new maps is more likely to be damaged or destroyed by a lahar than by fire," Scott said. "For example, a home built in an area that would be inundated every 100 years, on the average, is 27 times more likely to be damaged or destroyed by a flow than by fire. People know the danger of fire, so they buy fire insurance and they have smoke alarms, but most people are not aware of the risks of lahars, and few have applicable flood insurance." <p> At 14,410 feet above sea level, Mount Rainier is the highest volcano in the Cascade Range. It towers above urbanized lowlands near Tacoma, about 50 miles south of Seattle. During the past 20 years, much of the land at the base of the volcano and in the path of future lahar "runs" has become covered by numerous housing developments. <p> Because lahars are not closely linked to volcanic eruptions, they cannot be forecast by precursory earthquake activity which would allow downstream areas to be evacuated. <p> A variety of triggers can start the flows. "We can definitely say that many of the flows are not closely related to volcanic activity, but the exact cause is hard to pin down," Scott said. "Possible triggers are regional earthquakes, steam explosions or small earthquakes related to crustal loading by the mass of the volcano. There is no clear link between the flows and episodes of volcanism, and the unpredictability of the flows increases the danger." <p> He said the greatest risks in the populated lowlands are from large, gravity-induced flows with a recurrence interval of once every 500 to 1,000 years. "Mount Rainier has been weakened and altered by the constant percolation of hot, chemical-laden waters," Scott said. "large landslides or `sector collapses' of this weakened material disaggregate and mobilize rapidly to the muddy flows that pose great risk downstream." <p> Scott said he and other concerned scientists and public officials hope the new reports will heighten awareness of the lahar threat. He said one of the most important aspects of the new studies is their focus on flow probabilities, and how those statistics can be used by planners and public-safety officials. "we try to provide the science that help everyone concerned with growth management to make responsible decisions for the future," Scott said. <p> Definition and monitoring of volcanic hazards at Mount Rainier and other Cascades Range volcanoes, as well as many other volcanoes worldwide in cooperation with international agencies and foreign governments, is the mission of the Cascades Volcano Observatory (CVO), which was founded in response to the 1980 eruption of Mount St. Helens. The office and its staff have received many awards and citations for both domestic and international work. CVO is one of the leading observatories piloting "Decade Volcano" studies for the United Nations International Decade for Natural Disaster Reduction. Mount Rainier is one of 15 volcanoes targeted to further international understanding of mitigation from specific volcanic hazards. <br> <br> <dl> <dd> <a href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Publications/ordering.html"> <b>How to Order USGS Maps and Publications</b></a> </dl> </td> </tr> </table> <p> <hr> <hr> <map name="buttonbar"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/home.html" coords="0,0 94,61" alt="CVO HomePage"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Volcanoes/framework.html" coords="95,0 210,21" alt="Volcanoes of the World Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Volcanoes/MSH/framework.html" coords="95,21 210,42" alt="Mount St. Helens Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/LivingWith/framework.html" coords="95,40 210,61" alt="Living With Volcanoes Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Publications/framework.html" coords="211,0 290,21" alt="Publications and Reports Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Monitoring/framework.html" coords="211,21 290,42" alt="Volcano Monitoring Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Servers/framework.html" coords="211,40 290,61" alt="Servers and Useful Sites Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Hazards/framework.html" coords="291,0 352,21" alt="Volcano Hazards Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Projects/framework.html" coords="291,21 352,42" alt="Research and Projects Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Outreach/framework.html" coords="291,40 352,61" alt="Educational Outreach Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Glossary/framework.html" coords="352,0 480,21" alt="Hazards, Features, and Terminology Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Graphics/framework.html" coords="352,21 470,42" alt="Maps and Graphics Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Photo/framework.html" coords="352,40 470,61" alt="CVO Photo Archives Menu"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/Miscellaneous/ConversionTables/conversion_table.html" coords="471,0 539,61" alt="Conversion Tables"> <area shape="rect" href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/IndexList/framework.html" coords="540,0 617,61" alt="CVO Index - Search Our Site"> </map> <img border="0" height="62" width="617" alt="ButtonBar" src="https://web.archive.org/web/20100627181556im_/http://vulcan.wr.usgs.gov/Imgs/Gif/buttonbar.gif" usemap="#buttonbar"> <hr> <hr> <address> URL for CVO HomePage is: <a href="https://web.archive.org/web/20100627181556/http://vulcan.wr.usgs.gov/home.html"> <http://vulcan.wr.usgs.gov/home.html></a> <br> URL for this page is: <http://vulcan.wr.usgs.gov/Volcanoes/Rainier/Publications/debris_flow_maps.html> <br> If you have questions or comments please contact: <GS-CVO-WEB@usgs.gov> <br> 11/22/02, Lyn Topinka </address> </body> </html>