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This Radical Plan To Make Roads Greener Actually Works

Yet this enhanced connectivity often comes at a high social and ecological price. In the Amazon, Laurance has found, the vast majority of deforestation occurs near roadways; in Nepal’s Chitwan National Park, researchers have cautioned that roads stand to “cause dramatic reductions in tiger numbers” over the next two decades. According to Yakami, shoddily bulldozed Himalayan roads often leave behind wedges of spoil, which absorb water and trigger devastating landslides. “They’re taking roads everywhere, and that is not good for the environment,” he says.


CAPTION: Trees block dust that billows from an unpaved road in Makueni, Kenya.

CREDIT: Courtesy of Makueni County

In some cases, roads provide benefits and costs simultaneously. According to Yakami, new Nepalese roads have cut off mountain springs that have long sustained farms and households, but they’ve also revealed long-buried springs. Left to flow, the unearthed springs turn dirt roads into unstable slicks of mud. But channeled into taps and pipes, they can become important water sources for drought-stressed villages. This approach differs from Green Roads strategies in Ethiopia or Kenya, where roads have primarily been modified to capture rainfall rather than groundwater, but it similarly tries to synchronize road design with water delivery infrastructure.

But if roads can be recast as boons for water provision, will that framing provide a perverse incentive to build more of them? The very notion that a road can be “green” seems oxymoronic: A vast body of scientific literature demonstrates that roads befoul air and water, fragment ecosystems, introduce non-native species, and obliterate wildlife. In an email, Laurance expressed worry that “water harvesting might become a driver of road expansion in arid environments.”

Deligianni doesn’t dismiss those fears outright, but she doesn’t give them much credence. For one thing, most Green Roads for Water techniques have thus far been applied as retrofits to existing roads, rather than included in new ones. For another, she says, new roads are inevitable and, in many cases, desirable to local communities. So why not optimize the construction to come? “We’re looking at the projections for the future, and so many roads are going to be built,” Deligianni says. “We’re just trying to change the narrative and add some benefits.”

For now, the Green Roads movement, for all its institutional momentum, is moving forward in fits and starts. The idea, says the World Bank’s Singh Rao, requires “a paradigm shift in thinking and practice,” one that entails cooperation across agencies that tend to be siloed. In Ethiopia, Woldearegay says that agricultural ministries are enthusiastic about Green Roads and have incorporated them into their own technical guidelines, but road departments themselves have proved reluctant. “They don’t want the costs associated with designing and implementing [them],” he says. That’s the case in Kenya’s Makueni County, where limited budgets have hampered progress.

Yet these projects continue to attract attention: In recent months, Michael Maluki has given Green Roads tours to newspaper reporters, engineers, and farmers from neighboring counties. “We have been receiving so many visitors,” Maluki says. “The small things we do here, people are noticing.”