This article investigated the relationship between spatial knowledge and flood preparedness in Victoria Island. There is inadequate flood preparedness in Victoria Island, Lagos, Nigeria; because when the flood struck on 08 July 2017, several properties were destroyed without any extant means to salvage them. The variables employed to measure spatial knowledge include knowledge of: elevation of land, distance between Lagos lagoon and Atlantic Ocean, characteristics of surrounding water bodies and building–plot ratio. Major roads were used to subdivide Victoria Island into four zones. Zone A had 799 buildings, zone B had 813 buildings, zone C had 749 buildings and zone D had 887 buildings. Of the total 3248 buildings, 344 buildings were selected, and one household head per building was selected and systematically sampled.
The findings revealed that spatial knowledge accounted for only 25.8% of the explanation of inadequate flood preparedness. Only 6.1% of the respondents could distinguish height from elevation; those who explained density and setbacks correctly were 7.85% and 12.2%, respectively. Respondents who stated the distance between Lagos lagoon and Atlantic Ocean correctly and exhibited means of preparedness were 13.7%, respectively. However, 74.4% described the primary and secondary water bodies and their flow pattern correctly. Although inadequate spatial knowledge did not statistically account for poor flood preparedness, yet majority of the respondents neither prepared adequately for the annual flood event, nor exhibited adequate spatial knowledge. Therefore, other factors require investigation, whilst residents should acquire spatial flood-related education to influence their sense of flood preparedness.