Lagos, Nigeria’s economic hub, is the second-largest and one of the fastest-growing megacities in Africa (UN-HABITAT, 2010). The most recent census (NPC, 2006) puts the city’s population at eight million, a figure that is deeply contested (Potts, 2012). In 2009, UN-DESA estimated Lagos to have a population of 10.2 million, making it the twenty-first largest city in the world, with a projected rise to eleventh by 2025. With a growth rate of 3.1 per cent, Lagos adds an estimated 248,000 people to its population every year (Potts, 2012). Such a high level and rate of urbanisation without corresponding economic and infrastructural growth has been described as overurbanisation, leaving the city with a massive infrastructure deficit and about 70 per cent of the city’s population living in informal or ‘slum’settlements (UNHABITAT, 2003: 106; Adelekan, 2010). In addition, the geographical features of Lagos, particularly its coastal location and low-lying landmass portend a severe threat to this teeming megacity. These factors contribute to heightened concerns regarding city–coast risks in Lagos.