With an ever-increasing cost to extract dwindling raw materials, it's time to look at cities as urban mines. We're developing the tools to do that.
Many states in Nigeria are reeling from cholera outbreaks. They need better health and sanitation infrastructure to disrupt transmission of the bacteria which cause the disease.
Nigeria is rich in water resources. but poor management has led to water scarcity in the country.
Some water researchers are ignoring the evidence offered by sampling if it doesn't fit their preconceived notions. But science should always be honest and open.
Urbanisation will require massive amounts of water to sustain the livelihoods of millions expected to move into cities. This may happen at farmers' expense.
There's enough water under the ground to form a lake 100m deep over the earth.