Climate Resilience and Coastal Defense in Lagos

Climate Resilience and Coastal Protection in Lagos

Sitting at low elevation on the Atlantic coast, Lagos has rolled out drainage canal programs and mangrove reforestation efforts to protect its coastal neighborhoods from rising seas and erosion.

The Great Wall of Lagos: A Barrier Against the Ocean

The most emblematic coastal protection project in Lagos is the Great Wall of Lagos, an 8.5-kilometer sea defense barrier built to shield Victoria Island and the new Eko Atlantic district from erosion and sea level rise. More than 75 million cubic meters of sand were used to rebuild a shoreline that had retreated by several kilometers over the past century due to erosion. Since its completion, the wall has made roads passable that once flooded regularly and has encouraged reinvestment in previously abandoned properties along Victoria Island.

A Risk-Shifting Effect

This localized success is not without consequences: researchers and residents in nearby areas like Alpha Beach report that the wall has altered ocean currents, accelerating erosion along unprotected stretches of coastline, with more than 25 meters of land lost in some areas since construction began. This illustrates the complexity of coastal defense policy — protecting one neighborhood can shift erosive pressure onto another.

Urban Drainage: The Most Widespread Challenge

Beyond the sea wall, Lagos's aging and often poorly maintained drainage system remains the most common cause of urban flooding, particularly in Lekki, where densely populated former wetlands continue to sink. Eko Atlantic has its own modern underground drainage network designed to avoid the flooding that regularly affects the rest of the city, but that standard remains the exception rather than the norm across the wider metropolis. The 2024 and 2025 floods in Lekki and several other low-lying areas underscored the urgency of extending drainage and stormwater investment beyond the best-protected enclaves.

Mangroves and Nature-Based Solutions

Alongside heavy infrastructure, mangrove reforestation programs are underway in lagoon areas to stabilize banks and absorb some wave energy at a lower cost than pure civil engineering. iLagosCity notes that Lagos's climate resilience will depend as much on these nature-based solutions as on large engineering projects, in a city where several million residents live just a few meters above sea level.