In Darfur, a team of international geologists say they’ve discovered the imprint of a vast underground lake that could help put an end to the mass killings there. Researchers say the so-called “mega lake” is three times the size of Lebanon. Farouk El-Baz of Boston University’s Center for Remote Sensing said the potential water source could be the key to peace.

Farouk El-Baz: “What most people don’t really know is that the fight, the war, the instability in Darfur, is all based on the lack of water, simply put, nothing else. So now, if you find water for the farmers, if you find water, in addition to that to the nomads, if you find water in addition to these two for agricultural production, to feed them, to give them grain, then you resolve the problem completely.”

Up to 400,000 people have been killed in the conflict between Sudanese-backed militias and rebel groups. In a report last month the U.N. Development Program said widespread environmental problems are the root of the violence.