DEVELOPMENT OF A COMPUTER PROGRAM FOR HYDROLOGIC SIMULATION AND PREDICTIONS OF IDF RELATIONSHIPS FOR YOLA AREA USING LEAST-SQUARE REGRESSION METHOD

Abstract

MATLAB software was used to develop a computer program for the hydrologic simulation and prediction of IDF relationships of IDF relationships for Yola area by Least-square regression method of analysis. Rainfall data for a period of 30 years (1981-2010) for Yola. The data was analyzed by sorting and ranking the maximum rainfall depths with their corresponding depths and their return periods. The rainfall depths were converted to rainfall intensities. An algorithm was developed in form of a flowchart which guided the development of computer program using Sherman’s method. Values of rainfall intensities with corresponding durations and return periods were exported to the MATLAB program for modelling of station constants and simulation of IDF curves for the area. The station constants were obtained as n = 0.1081, c = 14.1771, and m = 0.5867 for Yola area respectively. These were used to produce IDF curves and mathematical model for Yola area. The IDF curves and mathematical models can be used in conjunction with Rational method for design of hydrologic structures of Yola metropolis.