The role of rainfall variability in reservoir storage management at Shiroro hydropower dam, Nigeria

Reservoir operation and management is usually patterned after the background of long standing water resources management experience. Reservoir management for optimum power production at any hydropower station requires constant assessment of the quantity of available water. The hydrographic responses of flow monitoring and statistical analysis of instrumental hydro-met records, especially rainfall and stream flow provide the necessary springboard for soundoperational decisions. Statistical analysis of hydrometeorological data (rainfall, inflow, reservoir storage and turbine release) at Shiroro dam was carried out with the aim of detecting spatio - temporal trends. Correlation and regression analysis were used to develop models for the variables. The correlation of between 0.120 and 0.774 revealed favourable relationships between the variables. This has invariably affected reservoir storage at the dam as excess water is released from the dam to sustain power generation over the years. It is  recommended that dam operators optimize the release of water from  Shiroro dam and ensure continuous monitoring of changes in  hydrometeorological variables to provide early warning systems for  effective performance of the dam and to protect downstream environment. Key words : Rainfall Variability, Reservoir Management, Environment, Dam, Storage