Russian scientists using satellite images have discovered an underground river in the Sahara desert large enough to supply an entire town with water, a Swiss Geological survey company said on Monday.

A team of scientists working for Geneva-based Geoinformation on a contract for the Mauritanian government used a Russian-invented technique to locate the river, buried under layers of volcanic rock 250 metres (820 feet) below the town of Atar.

Its 32,000 litre-per-hour flow will be enough to supply the daily needs of the Mauritanian town’s 50,000 inhabitants.