Analysis and Design of Sustainable Storm-water Management Practice in Ota, Ogun State, Nigeria
نویسندگان
1 Department of Civil and Environmental Engineering, Bells University, Ota, Nigeria.
2 Department of Civil and Environmental Engineering, Bells University, Ota, Nigeria.
3 Department of Civil and Environmental Engineering, Bells University, Ota, Nigeria.
4 Department of Civil and Environmental Engineering, Bells University, Ota, Nigeria.
5 Department of Civil and Environmental Engineering, Bells University, Ota, Nigeria.
6 Department of Civil and Environmental Engineering, Bells University, Ota, Nigeria.
7 Department of Civil Engineering, University of Ibadan, Nigeria.
doi
10.30501/jree.2025.521859.2387چکیده
This study analyzed and designed a sustainable storm-water management system in Ota, Nigeria, to create Intensity-Duration-Frequency (IDF) curves and determine precipitation depths and corresponding discharge rates for the 5, 10-, 25-, 50-, and 100-year return periods. The Langley Research Centre of the National Aeronautics and Space Administration provided 42 years of rainfall data (1982–2023) from the Prediction of Worldwide Energy Resources Project used for this study. A series of 24-hour extreme rainfall events was conducted, while mean, standard deviation, skewness and kurtosis were used to generate the sequence. Hazen's plotting positions was implemented to calculate the probabilities of reaching or surpassing ranked maxima for various return periods. Evaluation of the generated 24-hour extreme rainfall series resulted in selecting five probability distributions. Analysis of the 1982–2023 rainfall data revealed annual maximum rainfall values ranging from 27.44 mm to 166.1 mm, with 54.82 mm and 26.49 mm as the mean and standard deviation, showing a positively skewed distribution of 2.24 mm. Frequency analysis projected the highest recorded storm (166.1 mm), which had a 42 year return period between 1982 and 2023, with predicted rainfall intensities reaching 70.06 mm, 83.29 mm, 100.19 mm, 112.84 mm and 125.61 mm for the 5, 10, 25, 50 and 100 year return periods. Tests of goodness of fit selected the log-normal distribution as the best for calculating design storms. Analysis of the IDF disaggregated the 24-hour rainfall into 5-minute short periods, producing peak intensities of 125.6 mm/hr for 1000-year events and 10.8 mm/hr for 5-year events. These results emphasize the critical role robust data play in designing sustainable storm-water management systems, particularly in coastal communities like Ota, Nigeria. This study provides a novel, sustainable and adequate storm-water management design for the Bells Drive community, Ota, compared to the existing system, which is generally inadequate, resulting in flooding and pollution, especially during the peak of the rainfall season.
