Assessment of spatial and temporal variability of groundwater level in the aquifer system on the flanks of Mount Meru, Northern Tanzania

Abstract

Study region: Mount Meru located in Northern Tanzania. Study focus: Groundwater level monitoring is essential for uncovering the spatial-temporal variation of groundwater levels in a studied aquifer, helping discussions on the sustainable use and management of groundwater resources. This study analyses the spatial and temporal variability of groundwater level in the shallow aquifer system on the flanks of Mount Meru. Time series analysis of groundwater level measurements obtained in two hydrologic years: 2018–2019 and 2019–2020 is applied. New hydrological insights for the region: On the north-eastern flank of Mount Meru, at Ngarenanyuki, there is a rise of about 1.80 m between the static water levels in April 2018 and December 2020 in the shallow aquifer, whereas on the western flank, at Mamsa, there is a decrease of about 0.50 m between the static water levels in May 2018 and December 2020 in the shallow aquifer, this can be attributed to low/reduced recharge (due to very low hydraulic conductivity and semi-confined condition of the aquifer), or exploitation. Hence, the current pumping practices in the aquifer on the western flank should be restrained for sustainable groundwater management.

Keywords

• Groundwater level assessment
• Spatial-temporal variability
• Piezometric map
• Groundwater level fluctuation
• Mount Meru
• Tanzania