Demolishing Lagos informal settlements also destroys the city’s best defences against climate change

In a waterfront settlement in Lagos, Nigeria, I watched from the shoreline as two men worked a stretch of lagoon from their canoe.

One held the boat steady.

The other dived underwater a few metres, then surfaced with a bucket full of sand, emptied it into the canoe, and went under again for more.

They did this for hours, collecting as much sand as the canoe could hold without sinking before returning to shore.

That sand is sold to households and building sites across Nigeria’s largest city, including neighbourhoods much wealthier than the one the divers live in.

It gets packed around foundations and under floors to lift land and structures above water.

In a city where more than 40% of the surface is water or wetland and climate change is increasing flooding, sand is a flood defence.

I was observing the activities of the two men during my research into climate change impacts in Lagos.

As a climate social scientist who studies adaptation and migration, I set out my findings on adaptation infrastructures in a recent paper about 20 informal settlements in Lagos.

I wanted to understand how people living in Lagos’s poorest neighbourhoods built homes and resilient livelihoods, particularly in the face of climate change.

My research found that residents whose homes clustered along waterways, canals and shorelines – where flooding and coastal erosion hit hardest and have the least protection from climate change – had built organised systems for living with it.

And those systems supplied the rest of the city as well as themselves.

For example, residents dug boreholes to get water and then sold it to households in the settlement and to surrounding residences.

But city authorities ignore these activities.