Tchoffal only has one well to serve almost 400 people. It is a lifeline for the villagers.
"Ten years ago, you could dig just 10 metres and find water," says Omar. "But the drought means we had to dig this well to 40 metres.
"This water is shared by everyone - it's used for agriculture and people use it for drinking. But the water is extremely dirty.
"In N'Djamena, the water from our well is clean and clear."