Connecting resilience thinking to urban flooding

ABSTRACT Urban flooding as one of the environmental disasters in most of our cities both in developed and developing countries is drawing increasing attention.Nigeria is not an exemption; so Ondo city, Ondo State. This is due to intensive prolonging rainfall in which climate change might be accounted for. The rate of rapid urbanization in the city as well as city’s population growth which made it the second largest city has been necessitating details on flood management, amongst which land use and land cover plays an important role. Continuous alteration of the environment most especially the landscape to give way to increase in built-up city has abridged the functionality of hydrological structures. In other words, increase in impervious surfaces over time decreases rainfall penetration into the earth and decrease in vegetation, lack or no drainage in most part of the city. This has really intensified overflow into adjourning rivers or streams thus, becoming an environmental degradation negligent causing great damage to the people and the environment. This research’s aim is to explain the influence of land use land cover on urban flooding in prone areas of Ondo, i.e.; understanding the relationship between land use land cover and the flood level in prone areas in Ondo city, Ondo State, Nigeria. The research approach used is primarily secondary quantitative research strategy. This type of research strategy is collecting primary data from secondary data which is meant for another purpose; from satellite imageries of land use land cover to get the measurement of these land use in the city by creating a grid on the geo referenced city map and dividing into sixty-four (64) cells or zones of 1.4km by 1.4km each of observation units. The total study area boundary covers 11.2km by 11.2km, the land use and flood level is then measured in each zone. While the primary technical approach applied was quantitative data analysis acquired through the digitized satellite imageries and secondary data on flood level from research institute, government agency and the field survey, these quantitative data were analyzed using multiple regressions in SPSS to see the relationship between the flood level and the land use/land cover. From the analysis on the imagery, it could be seen that as at 2016 vegetation or green area had been reduced by 51.82% from 1986, while built up area has also increased by about 24% in 2016. While water body and drainages volume increases as the city grows, due to encroachment of the built-up areas and reduction in vegetation. In the context of Ondo city, the main land use influencing flood level most in the city is the drainage with a statistical significance of P value < .001, with an unstandardized beta coefficient of 7.994 standardized beta co efficient of .372 which implies that drainage has positive effect on the flood level. Observation during field survey showed that most drainage have been blocked and the flow of water courses hindered, lack of and poor drainage facilities also attributed to these from the observation during the field survey when the measurements of flood level were taken. The green area has a negative effect on flood level, which implies that; has the green area increases the flood level will decrease in the city. Vegetation statistical value is with a p value< .001; this shows the importance of having vegetation in the city. This research therefore has provided insights to empirical data, key analytical and conceptual frameworks that can be used to detect and address urban flooding issues. Keywords Urban-Flooding,Urban-Structures (Spatial /Urban Planning), land use land cover, Resilience-thinking and Climate Change.