The Columbia River Bar (USA) is one of the most dangerous and challenging navigated stretches of water in the world. However, successful passage grants access to several inland ports and waterways through which transportation between the US Pacific Northwest and the world averages 40 million tons of cargo valued at $20 billion each year. During 2011 and 2012 OMC International performed under-keel clearance (UKC) modelling and detailed validation studies for the Columbia River Bar Pilots including measurement and analysis of the motion of 24 vessels crossing the Columbia River Bar in moderate to high seas. Measurements and detailed UKC modelling reveal that UKC needs to be carefully managed on the Columbia River Bar. Conditions under which touch bottom events might occur vary greatly with vessel class and transit direction such that no clear “rules of thumb” can be established to ensure risky transits are avoided. A web-based demonstration DUKC® system has since been established and this has been used by the Columbia River Bar Pilots to predict and/or analyse the UKC of more than 130 deep-draft transits.
Click here to read the full article: https://omcinternational.com/wp-content/uploads/2010/06/Coasts-Ports-2013-Under-keel-Clearance-at-the-Columbia-River-Bar.pdf