Groundwater Recharge Response to Climate Variability in Chanchaga River Basin, Nigeria

Abstract

Abstract Variability in both precipitation and temperature directly influences the hydrologic cycle and indirectly on freshwater resources particularly groundwater which is the major source of domestic. agricultural and industrial water supply in the arid and semi-arid areas of Nigeria. This study examine the influence of climatic variability on groundwater recharge in Chanchaga River Basin, Nigeria. Estimation of groundwater recharge over the basin was computed using Kumar and Seethapathi empirical formula. Thirty year recharge data (1986 - 2015) were generated. Rainfall and temperature records for the same period were also collected and analyzed using descriptive statistics, correlation and multiple regression analyses. It is established that rainfall is the ultimate source of groundwater recharge in the basin. The results also indicate that annual rainfall ranges from 1026.6 mm to 1967.7 mm /yr. Temperature hovers between 32°C and 34°C. This impact on groundwater with an annual recharge mean of 270 mm/yr. A coefficient of 17.5% of the total annual rainfall was obtained as groundwater recharge. Recommendations includes prioritizing groundwater usage al water-stressed dry periods, continuous monitoring to forestall depletion and pollution.