This research examined the effects of flooding on developed property values in Port Harcourt Metropolis, Rivers State Nigeria. The methodology involved the sub-dividing of the Metropolis into four sub basins (SB1, SB2, SB3, SB4) with the aid of the topographic map of Rivers State. Data collection was by means of primary and secondary sources of information. Three hundred and sixty respondents were selected and interviewed using a precoded questions, as well as field measurements. Descriptive statistics such as frequency and percentages were used as well as inferential statistics such as Spearman’s rank statistics was also used for data analysis. Findings showed that about 51.9% of respondents agreed that there was flooding problems in Port Harcourt Metropolis. However, 43.1% attested that the flood water lasts up to 30days before the water dries up. On developed property values the study found that (61.1%) of respondents affirmed that flooded properties were abandoned during and after flooding. Also (20.8%) of respondents agreed that the buildings within these flooded areas has depreciated in structure and value, while (18.1%) affirmed that the rent were low in such flooded areas. Drainages were available, but substandard, therefore blocked with debris and could not evacuate storm water. Statistical test of the degree of relationship proved that there was a very strong relationship between flood frequency and drainage condition in the Metropolis (P<0.01 (n=40). The study recommended that government should prepare a drainage plan for the Metropolis. Furthermore, a comprehensive drainage and infrastructural planning works should be embarked upon urgently by the relevant agencies by way of desilting all drainages and waterways, identification and demolition of structures on flood plains and construction of storm water channels in flood prone areas to combat the menace of flooding in the Metropolis.
