Measuring Sahel aquifers: core drills and piezometric sensors
A technical analysis on groundwater monitoring to prevent over-extraction across solar pumping wells.
Pairing solar panels with deep artesian wells across the northern Sahel eliminates diesel dependence, yet risks depleting vulnerable aquifers if piezometric levels remain unmonitored. In Dori, field technicians set pressure transducers within the stilling pipe at 85 metres depth.
Data series confirm recharge occurs within a narrow six-week window between July and September. Static groundwater elevation rebounds by approximately 4.2 metres during this phase, followed by a linear drop averaging 35 centimetres monthly throughout the dry season.
Calibrated flow control valves mounted upstream of distribution taps prevent pumps from drawing at maximum continuous capacity during peak solar radiation, spreading extraction evenly over eight daylight hours.
Publishing these hydrogeological charts enables the municipal council to share actual aquifer reserves with village leaders, establishing scheduled watering times for nomadic herds.