Application of Statistical Model of Water Level Variation in Reservoir Bauchi Township

Hydrological analysis and designs require information on flow rate at any point of Interest along a stream. However, in most cases, this information may not be available in sufficient quantity due to lack of continuous record of stream gauging or non-availability of records. Faced with these difficulties, engineers and planners resort to the use of mathematical approaches such as Synthesis and simulation as tools to generate artificial flow sequences for use in design regarding water supply, structures sizes flood control measures e.t.c. The water resources planners and designers will therefore continue to employ modeling techniques to simulate hydrologic processes and catchment behavior Mustafa and Yusuf (1997). The source of a water supply for the study area is through Gubi dam. During rainy season the reservoir level begin to increase up to a maximum value of 557.37m especially from the period of September to November, while at the period of December to around June draw down to minimum of 553m.The analysis of result was obtained by Least square method and moving average method of order 3 to forecast the future drawdown/rise up of water level in the reservoir and the future equation for water drawdown/rise up of reservoir. In the analysis of result, the regression equation is obtained to be equal to Water level(Y) = 556 + 0.00228 Month(X). In the trend analysis the equation was obtained as Yt = 555.774 + 2.43E-03*t with the graph plotted for the trend. The seasonality was removed living behind the trend line equation as seen from the graph. These equations can be used to determine the reservoir water level at any time t (month). In the second analysis by the average method of order 3, the result in the first forecast that is in 1998 the forecasted drawdown/rise up is 556.734 while upper and lower values are 554.944 and 558.524 respectively. The analysis was forecasted using average method of order 3 for the period of 30years that is from 1997 to 2027.