Fossil water

Fossil water is groundwater that infiltrated thousands, even tens of thousands of years ago, during the humid periods of the "green Sahara", and has been trapped since in deep aquifers. It is practically not renewed on a human timescale — a precious resource to be used with care.

Details

• Some water pumped today in northern Niger fell as rain 20,000 to 40,000 years ago
• Datable by isotopic methods
• Non-renewable on a human scale — abstraction can durably lower aquifer levels
• Justifies the hydrogeological studies preceding each LPDD / NGO Tidène borehole

Related terms

• Tim Mersoï basin — The Tim Mersoï basin is a vast aquifer reservoir of about 115,000 km² in northern Niger, between the Aïr massif and the Algerian border.
• Solar borehole — A solar borehole is a deep borehole (typically > 80 m) equipped with a submerged pump powered by photovoltaic panels.
• Water access in Niger — In Niger, access to drinking water is among the lowest in the world: 2 out of 5 Nigeriens have no access to safe drinking water.