A billion-dollar hydroelectric dam development in Indonesia that threatens the habitat of the world's rarest great ape has sparked fresh concerns about the impact of China's globe-spanning infrastructure drive. The site of the dam in the Batang Toru rainforest on Sumatra island is the only known habitat of the Tapanuli orangutan, a newly discovered species that numbers about 800 individuals in total. The $1.6 billion project, which is expected to be operational by 2022, will cut through the heart of the critically endangered animal's habitat, which is also home to agile gibbons, siamangs and Sumatran tigers.

Indonesian firm PT North Sumatra Hydro Energy is building the power plant with backing from Sinosure, a Chinese state-owned enterprise (SOE) that insures overseas investment projects, and the Bank of China, company documents show. Chinese SOE Sinohydro, which built the mammoth Three Gorges Dam, has been awarded the design and construction contract for the project.

The development is one of dozens being pushed by the government to improve electricity supply throughout the sprawling archipelago, parts of which are regularly plagued by blackouts. But the Chinese-backed project has sparked fierce resistance from conservationists, who say the potential environmental risk has already seen the World Bank Group shy away from involvement. Its Chinese backers appear undeterred, however, something critics say underscores the troubling environmental impact of Beijing's trademark "Belt and Road Initiative", which seeks to link Asia, Europe and Africa with a network of ports, highways and railways.

"This issue is becoming in some ways the face of the Belt and Road initiative," Professor Bill Laurance, director of the Centre for Tropical Environmental and Sustainability Science at James Cook University in Australia, told AFP.

Until recently, scientists thought there were only two genetically distinct types of orangutan, Bornean and Sumatran. But in 1997 biological anthropologist Erik Meijaard observed an isolated population of the great apes in Batang Toru, south of the known habitat for Sumatran orangutans, and scientists began to investigate if it was a unique species. Researchers studied the DNA, skulls and teeth of 33 orangutans killed in human-animal conflict before concluding that they had indeed discovered a new species, giving it the scientific name Pongo tapanuliensis or Tapanuli orangutan. The 510-megawatt dam, which will supply peak-load electricity to North Sumatra province, will flood part of the ape's habitat and include a network of roads and high-voltage transmission lines.