How to Turn a Desert into a Forest

Ties van der Hoeven can already picture it: Not too far into the future, the bearded 41-year-old engineer will be standing on the hills above Lake Bardawil. At the moment, it’s little more than a diminished lagoon amid parched land on the North Coast of the Sinai peninsula, the battered triangle that connects Africa to Asia. Someday, however, Van der Hoeven believes it will be a fully restored reservoir, ringed with trees and wetlands, and teeming with fish, sea grasses, and fields from which the locals will once again harvest vegetables. 

“This used to be the land flowing with milk and honey, the promised land, the Garden of Eden,” the Dutch engineer says. “We can turn it into paradise again.”

Van der Hoeven might be a maverick morphological engineer, having grown up with hippie parents on a sailboat. But his vision is no pipe dream. Engineers around the world have already shown that it is possible to effectively regreen deserts and arid plains.

One of the most spectacular examples is the Loess Plateau in northwest China, an area roughly the size of France and home to more than 50 million people. Launching its rehabilitation project in 1994, the Chinese government and the World Bank restored the once fertile region over a period of 25 years by banning tree cutting, terracing the terrain, planting indigenous plants and reestablishing a healthy ecosystem. “2.5 million people were lifted out of poverty,” the World Bank reports. “Through the introduction of sustainable farming practices, farmers’ incomes doubled, employment diversified and the degraded environment was revitalized.” All this for a project cost of $252 million. Adjacent Mongolia, too, just announced a plan to plant one billion trees by 2030 to combat desertification. 

The second monumental example is the Great Green Wall, an 8,000 kilometer greenbelt traversing 11 countries of Africa’s Sahel region, including Senegal, Mali, Nigeria, Niger and Ethiopia. Temperatures there are rising 1.5 times faster than the global average, and the project’s urgency is matched by its ambitious scope. Governments, locals, activists and engineers hope to restore 100 million hectares of degraded land by 2030 and bring drought relief to some of the poorest regions in the world. Supported by 20 African countries, the UN, the EU and the World Bank, the Great Green Wall is about 15 percent complete. 

According to its initiators, it will be “the largest living structure on the planet, three times the size of the Great Barrier Reef,” and “is already bringing life back to Africa’s degraded landscapes at an unprecedented scale, providing food security, jobs and a reason to stay for the millions who live along its path.” 

Outside of these massive projects, there are innumerable smaller reforestation efforts across the world: WildEast in England, Familial Forestry in India, and Geoff Lawton’s Permaculture Research Institute in Australia. The United Nations declared ecosystem restoration a priority and hopes to restore 350 million hectares in 70 nations by 2030. 

The logic: It was humans who caused the loss of roughly 50 percent of biomass over the last 50 years, and accelerated desertification by grubbing and overgrazing once fertile land. This human activity set into motion a vicious cycle of erosion, desiccation and desertification. Van der Hoeven named his company The Weather Makers, after Tim Flannery’s book about the Anthropocene. The plot: Humans caused desertification, and humans can also reverse it.

An experienced large-scale dredger, Van der Hoeven was originally asked only for advice on how to dredge the Sinai lagoon, which the Egyptian government believes would boost its fish stock. But the longer he studied its geological makeup, the more intrigued he became. Could the 1.2-meter-deep lagoon, which was once 20 to 40 meters deep, be returned to its original state as the first step in restoring the peninsula’s ecosystem?

When he saw the documentary Green Gold by the journalist and environmentalist John Liu about the transformation of the Loess Plateau into a green oasis, he was hooked. He got to work mapping out the steps to regenerate the ecosystem of the Sinai. “Heck, we can change the livelihood for hundreds of thousands of people!” he says. 

He was already familiar with the Middle East, having spent years dredging the Dubai coast to build the city’s artificial palm-shaped islands. “Money, alcohol, parties,” he recalls. “I lost a bit of my soul.”

After spending a week on the Loess Plateau to study how the Chinese accomplished the regreening, he and his team flew to the presidential palace in Cairo two years ago to pitch their plans to representatives from President Abdel Fattah el-Sisi’s government. The Sinai region is one of the most hostile and barren on earth. But just like the Loess Plateau, it was probably fertile as recently as 5,000 to 8,000 years ago. Cave paintings show trees and plants. “The solution is relatively simple, though it is of course hard work,” says Van der Hoeven. “The land tells you where to start.” 

He mapped out restoration in five steps. Steps One and Two: revitalize the lagoon and expand the wetlands around it. “If you want to do something to help planet earth you need to restore the coastal areas because they are by far the most productive systems in the world,” he says. Step Three: Desalinate “the rich marine sediments in the lagoon, the indigenous soils” as fertilizer to regenerate the water cycle, grow salt-tolerant plants and aquatic greens. Step Four: fog nets capture freshwater condensation on the nearby hills and use it to regreen the desert. And finally, Step Five: the natural watersheds are restored. “By adding the vegetation cover and increasing humidity, you get rain again,” Van der Hoeven explains. 

These five steps follow the same basic principles that have successfully regreened other areas of the world, with modifications to customize the process for the Sinai region specifically. 

“If we were to reverse engineer [the downward spiral of desertification], we might have the possibility to return to the virtuous circle instead of the vicious cycle feedback loop,” John Liu says via Zoom from his patio in Irvine, California. “This is the most serious moment in civilization, where we can see predictable catastrophic and unnecessary outcomes of human activity. We are obligated to understand this and find a solution, not only for ourselves but for life and human civilization.“

The process of regreening the Sinai would take 20 to 40 years, as it has with comparable projects, simply because it takes decades for the lost plants and trees to grow back, but progress would be noticeable after just three years and could be sped up by bringing in additional water. The cost of the entire project: $31 to 39 billion — a huge sum, but tiny in comparison to the boon regreening would bring.

As just one example and based on his calculations — which themselves are based on the historic data from when the lagoon was at its original size — Van der Hoeven is convinced that the hydraulic regeneration of the lagoon and regenerative fish management can provide 50,000 tons of fish (up from the 5,000 tons of fish that are there now) and thus feed the locals like it did in the past. 

The Egyptian government seems willing to fund at least the first phase, but unrest in the Sinai has so far delayed the project. Still, Van der Hoeven hopes to begin soon. He believes the restoration will serve as a “peace plan,” and help bring stability and prosperity to a region in crisis. Local conflict can quickly derail any well-intentioned environmental project, as has happened with the One Million Trees initiative in Dubai, where megaprojects diverted the tree nursery’s supply of water and destroyed many of the saplings.

A crucial element in Van der Hoeven’s plan are the “eco-machines,” or “living machines,” created by now-retired biologist John Todd, a pioneer in ecological design and founder of the New Alchemy Institute in Massachusetts. 

Van der Hoeven has built an eco-machine in his backyard in the city of s’Hertogenbosch. From the outside, the setup looks like a greenhouse. Inside are transparent plastic barrels where Van der Hoeven grows phytoplankton, the basic component of the food web, as well as algae, fungi, worms and insects that restore soil health. Condensation is captured and fed back to the plants as freshwater, allowing the eco-machines to revitalize the marine sediments. Once restored, these sediments will eventually support larger plants and fish, like tilapia. The process also cleans the water, until life inside the barrels becomes self-sustaining and the greenhouses are no longer needed. 

Now imagine this process repeated 100 times across the banks of the Bardawil lagoon, slowly restoring the fertility of the land. In addition to furthering biodiversity and lowering the region’s temperature, the rejuvenated peninsula would serve as a carbon sink “for billions of tons of CO2,” as Van der Hoeven estimates, though it’s impossible to verify this ambitious estimate.

More importantly, Van der Hoeven believes that restoring the watersheds in one crucial region such as the Sinai can have “consequences for the world climate. We are changing the wind pattern and the weather. The Sinai is the climate heart of the earth, an acupuncture point of climate change.” Currently, the Sinai draws moist air from the Mediterranean Sea, but regreening it would likely increase rain across the Middle East. “It’s not just Egypt; it’s really on a planetary scale, and this is the only scale that makes sense given the size of the problem,” says John Liu.

Ecosystem Restoration Camps, where John Liu is an adviser, teach the process of restoring the land all across the earth, including North America, where many regions also suffer from drought. “We need to have strategies on reversing human climate change. This is the holy grail. The size of the solution needs to be equal to the size of the problem.”