Dangote Sandbar Breakwater Beaches and Dunes
Lekki, Lagos State, Nigeria Preventing erosion using nature-based solutions at Dangote’s marine terminal. The coastal system of Nigeria is unique. Regular swells arriving at the coast at a relatively constant angle combined with a uniform steep and sandy coast result in a large and unidirectional longshore sediment transport. However, the coastal system of West Africa is highly affected by human interventions, such as maritime infrastructure, and is aggravated by climate change. Such infrastructure interrupts the steady eastward transport of sand, leading to coastal erosion and loss of habitat. The Dangote Oil Refining Company’s new greenfield refinery, polypropylene, and fertilizer plant’s own infrastructure required protection against the heavy wave energy. A conventional rubblemound breakwater would cause a rapid advance of the coastline on the updrift side, ultimately burying the expensive armor rock. Instead, in 2016, CDR International and Svašek Hydraulics, both coastal engineering specialists, developed and designed a sandbar breakwater concept to be constructed mainly out of sand. The use of natural processes and the natural availability of construction materials made it a cost-effective design. In 2018 in less than five months, the dredging contractor Boskalis constructed the breakwater. Since, natural wave action has been shaping the sandbar breakwater and adjacent updrift coastline as designed.
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