Mr. Amer, the farmer based here, proudly showed visitors his efforts to irrigate fruit and tomato fields using rubber tubes, instead of just funneling it through earthen ditches that allow most of the water to evaporate unused. Little hoses spray the crops with water instead of wastefully soaking them.
But he also pointed out two local wells where the water is dropping at the astonishing rate of almost 60 feet a year, causing the land to subside. Nearby, sinkholes in the arid soil of his property are growing longer and deeper every year.
“We have been suffering for years from this,” he said, gesturing at a cast-off drill rig that broke after going down too deep into the earth.
The Yemeni engineers working on the World Bank project concede they have had tremendous difficulty convincing other farmers — and even government agencies — to take their efforts seriously.
“There is no coordination with other parts of the government, even after we explain the dangers,” said Ali Hassan Awad. “Prosecutors don’t understand that drilling is a serious problem.”
Mr. Eryani, the water minister, takes the long view. Yemen has suffered ecological crises before and survived. The collapse of the Marib dam, for instance, led to a famine that pushed vast numbers of people to migrate abroad, and their descendants are now scattered across the Middle East.
“But that was before national borders were established,” Mr. Eryani added. “If we face a similar catastrophe now, who will allow us to move?”