HISPANIOLA – On the Caribbean island of Hispaniola, home to the sovereign nations of the Dominican Republic and Haiti, two large lakes are rising dramatically.
Lake Azuéi in Haiti submerged an entire community; across the border in the Dominican Republic, Lake Enriquillo has risen nearly 33 feet in just 10 years. As their land flooded, many farmers began cut-ting down trees to make charcoal to earn a living, leading to deforestation.
Scientists from across the globe have tried to solve the mystery behind the rising lakes. Some think climate change is to blame, arguing that warming sea created more evaporation and clouds, which led to more rainfall. But if true, that would be strange, because in most of the world climate change is causing lakes to shrink.
The phenomenon is spur- ring calls for more research to help explain – and mitigate – the situation. Until scientists are able to identify the cause and work toward a solution, thousands of farmers on this Caribbean island will have to adapt.
In Haiti and the Dominican Republic, the lakes are flooding farmland, swallowing communities and leading to deforestation, baffling climate scientists.
LETANT, Haiti—On a recent calm day, the surface of Lake Azuéi has no waves, not even any ripples. Pillars of pastel-colored concrete break the still surface, the tops of what once were houses. They are all that’s visible of the community that once thrived here.
Alberto Pierre, a skinny, wide-eyed 25-year-old, said the submerged village where he grew up wasn’t even near the lake. “The water used to be many kilometers from here.”
Lake Azuéi, the largest lake in Haiti, lies about 18 miles east of Port-au-Prince, the capital, nestled along the border with the Dominican Republic. Also known as Étang Saumâtre, the lake rose so much between 2004 and 2009 that it engulfed dozens of square miles.
“At first we put rocks so it wouldn’t come into our houses,” Pierre says. “But then the water just overran the rocks.” Families in the village of Letant began abandoning their houses, building huts on higher ground using wood, tarps, whatever they could find. By 2012, all 83 houses had been vacated.
“We don’t know why the water is rising,” he says.
In fact, nobody does. There seems to be no logic to the lake’s rise. Experts from the United Nations, a French engineering firm, a Dominican Republic university, a New York City college and many others have looked for clues to explain the rise of Lake Azuéi and neighboring Lake Enriquillo, just across the border in the Dominican Republic. But few of the theories seem to hold water. Some now hypothesize the phenomenon is related to climate change, but the evidence is counterintuitive: Unlike ocean levels, which rise with climate change, lakes tend to shrink.
On a sunny hill overlooking a valley of shrubs, yellow grass and maize, Deodat Madembwe watches a team of masons make bricks for an elementary school he’s building.
As a young man growing up in central Tanzania, Madembwe too was a mason. Back then the most popular way to make bricks was to mould them loosely out of dirt and clay and then burn them in a tanuru – the Swahili word for a kiln. But to heat the kiln was to wreak havoc on the local environment.
“People cut trees to burn bricks,” he explained. To burn enough bricks for about five houses, they’d have to fell 10, even 20 trees. Burning the trees releases CO², contributing to climate change, and deforestation means there are fewer trees left to combat it. As Tanzania’s population grew, more and more houses arose and the landscape suffered. “We [were] making a desert,” said Madembwe.
But today, on a sunny plateau above Mbeya, the masonry unfolding before Madembwe’s eyes is of an entirely different breed. Two men with shovels quickly mix dirt they’ve sifted with a bit of sand and cement. They add water and shovel the mixture into a small steel device. A third man closes the heavy metal lid and pulls down hard on a long green lever. He releases, and a perfectly rectangular gray brick rises up.
NGOs, governments and local cooperatives have been experimenting with so-called compressed stabilised earth blocks (CSEB), a green alternative to tree-consuming burnt bricks, on a small scale for years. But they may soon rise to global prominence, prompted in part by interest from an unlikely party: the largest cement manufacturer in the world.