The Ubari Sand Sea is a vast area of towering sand dunes in the Fezzan region of south-western Libya. But 200,000 years ago, this was a wet and fertile region with plenty of rainfall and flowing rivers. These rivers fed a vast lake, the size of Czech Republic, in the Fezzan basin called Lake Megafezzan. During humid periods the lake reached a maximum size of 120,000 square kilometers. Climate change caused the region, a part of Sahara, to gradually dry up and between 3,000 to 5,000 years ago, the lake evaporated away into thin air. Traces of this great lake still exist today in the form of micro lakes scattered among the towering dunes like wet patches in the desert. Currently there are about 20 lakes in the Ubari Sand Sea – beautiful palm-fringed oases that appear like anomalies in the harsh desert environment.
Among the most picturesque of the lakes are Gaberoun and Umm al-Maa (the Mother of Water). Located besides the ruins of the old village, Gaberoun is the one tourists mostly visit. There is a rudimentary tourist camp on the shore, including an open patio, sleeping huts, and a souvenir shop. There are two more beautiful lakes – Umm al-H’isan (the Mother of the Horse), also spelt as Oum El Hassan, located north of Gaberoun; and another one at Tarhouna, about 11km from Umm al-H’isan. These are, however, rarely visited by tourists.
The Ubari lakes are very salty. This is due to the fact that these lakes are being continuously evaporated and have no rivers replenishing them (Libya has no perennial rivers that persist year-round). This has caused the dissolved minerals in the lake waters to become concentrated. Some of these lakes are nearly five times saltier than seawater. Some take on blood-red hue from the presence of salt-tolerant algae.
Although the Ubari Lakes are not exactly shallow, ranging from 7 to 32 meters in depth, they are at the risk of drying out. The waters in Sahara’s underground aquifers, that were deposited tens of thousands of years ago in much wetter times, is limited and this is already declining thanks to the increasing use of aquifer water by growing human populations. About three decades ago the Libyan government undertook an ambitious project called Great Man-Made River, aimed at drawing water from the aquifers beneath the Fezzan region via a network of underground pipes to make the desert bloom. The project, if successful, will drain these enormous reserve of fresh water in just 50 to 100 years.