Why does Nigeria keep flooding?

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Heavy rainfall has certainly increased the likelihood of rivers overflowing and flash floods.

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But it's not just rain falling in Nigeria itself.

Heavy precipitation upstream on the Benue and Niger rivers - in Cameroon, Mali and the country of Niger - contributes large volumes of water to Nigeria's river system, according to Zahrah Musa at the IHE Delft Institute for Water Education.

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Nigeria's three main electricity-generating dams, at Kainji and Jebba on the Niger river and the Shiroro dam on the Kaduna River, "have become bloated" by the heavy rains and excess water has had to be released downstream over the past month, says Hussaini Ibrahim, of the Niger State Emergency Management Agency (NSEMA).

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Nigeria's population is expanding rapidly, currently estimated at 186 million, and the lack of proper town planning can make flooding worse in urban areas.

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Because of the unregulated nature of town planning, there's also limited information on how much land has been built on and therefore little assessment of the impact.

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If the impact of flooding is to be reduced in the future, the consequences of rapid urbanisation and poor urban planning need to be addressed.

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