Resource 6: Nigeria’s sinking coastlines
Background information / subject knowledge for teacher
New research suggests that climate-related sea level rise is likely to put 80% of Nigeria’s coastline at risk of being swept away.
The most threatened coastline in Nigeria is on Victoria Island off the Lagos coast. Besides the possible loss of property, the land mass of Victoria Island and nearby Lekki could shrink by as much as 230 sq mi due to coastal erosion and rising sea level.
Between 600,000 and 1.5 million people on the island and adjoining areas could be displaced. Some bridges in the area are already in danger of collapse due to erosion.
Nearly 100 years ago, the fine white sands of Victoria stretched for about 0.7 miles wide. Today, the beach has been eaten away to less than a third of a mile wide. Experts say the rapid erosion of the island and, indeed, of most of Lagos’s coastline, can be largely attributed to two breakwaters known as the ‘East and West Moles’, which the British colonial government constructed between 1908 and 1912. The moles were built to protect Lagos’s valuable harbour from the fierce action of the waves and to prevent sand from entering the deeply dredged harbour on the ocean surge. Unfortunately, the harbour’s gain was Victoria Island’s loss. The moles altered the balance between the Lagos coast’s rate of erosion and the rate at which ocean sediments are deposited.
To slow the rate of erosion, local authorities have come up with a beach nourishment strategy. Since 1963, more than 600 million cubic feet of sand have been dumped on Bar Beach to check the ocean surge. That’s enough to bury a football field more than 1.2 miles deep in sand.
These efforts have proven ineffective, as the ocean continues to swallow up the beach at a rate of 16 feet a year. Today, the ocean is barely more than 130 feet from the island, which is believed to be half a foot below sea level.
Adapted from: Find Articles, Website