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Understanding Dredging

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CEDA-UK Tuesday 5 March John Sargent's Lecture: The Plastic Problem


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Every year, millions of tonnes of plastic enter the ocean. Ocean plastic pollution impacts the environment, the economy and humans. 

A significant percentage of the plastic that enters the world’s oceans drifts into large systems of circulating ocean currents, also known as gyres. There are five gyres in the world’s oceans and the largest of these is known as the Great Pacific Garbage Patch, halfway between Hawaii and California. Once trapped in a gyre, the plastic will break down into micro plastics and become increasingly easier to mistake for food by sea life - and so it enters the food chain. Plastic pollution is conservatively estimated to have a yearly financial damage of 13 billion USD.

On September 8, 2018, The Ocean Cleanup launched their first ocean cleanup system from San Francisco out into the North Pacific, en route to the Great Pacific Garbage Patch. This deployment gives The Ocean Cleanup an opportunity to test the technology at full scale. The system will be monitored closely, and the lessons learned will be implemented in the design of the next following system, before starting the scale-up to full fleet. The Ocean Cleanup aims to launch 60 cleanup systems in the Great Pacific Garbage Patch, and in doing so, be able to remove 50 % of the patch every 5 years. 

Speaker: Lonneke Holierhoek

Lonneke Holierhoek, has a Master’s degree in Technical Mathematics from Delft University of Technology (1993) and graduated as a Civil Engineering Surveyor / Quantity Surveyor with the Chartered Institution of Civil Engineering Surveyors (2002). Lonneke has over 20 years of experience in the maritime and offshore construction industry, from companies such as the Dutch dredging and offshore contractor Van Oord, its predecessors Ballast Ham Dredging, HAM/Hollandsche Beton Groep as well as Offshore Independents. Lonneke started her career in the marine offshore industry as a risk analyst after which she transitioned into increasingly more managerial roles. She joined The Ocean Cleanup as COO in 2017, when the team transitioned from inventing to execution of its ambitious plans.

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ICE, London,
5 March 2019 - 5 March 2019
17.30- 20.30 hrs

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The Plastic Problem