Water levels in lakes is a determinant of water availability for optimum water resources planning and ecosystem functioning. This study examines the surface water fluctuations in Kainji and Shiroro Lakes between 2008 and 2022 (14 years) using satellite altimetry. The purpose is to monitor the effect of precipitation, as an indicator of climatic variability on the water levels in the lakes considering their use for hydropower generation and flood control .From the observed values, there was no significant difference in water levels with the highest recorded at Kainji Lake as 138.84m and the lowest as 125.77m, however, there was significant difference in the  area coverage with the highest value as 1311.16km²  and lowest value as 761.15km².Same trend was noticed for Shiroro Lake where the highest water level was 381.92m and lowest as 356.97m; there was a marked difference in area coverage with the highest area being 361.61km² and lowest 104.36km² . A further analysis was done to assess the spatiotemporal trend of the rainfall at the Kainji and Shiroro Lakes from rainfall data derived from TAMSAT. Using Mann Kendall (MK) and Spearman’s rho tests for the 14-year period, trend analysis for the Kainji Lake showed a slight positive trend for precipitation at a 5% significance level; with mean annual rainfall of 1137. 7mm.At the Shiroro Lake, there was no positive trend at a 5% significance level. The mean annual rainfall recorded was 1318.6m.

 

Key Words: Precipitation, Significance level, Mann Kendall, Rainfall, Trend