China's plan to blast open more of the Mekong River for bigger cargo ships could founder on a remote outcrop of half-submerged rocks that Thai protesters have vowed to protect against Beijing's economic expansion in Southeast Asia. Dynamiting…of the Mekong between Thailand and Laos will harm the environment and bring trade advantages only to China, the protesters say.

"This will be the death of the Mekong," said Niwat Roykaew, chairman of the Rak Chiang Khong Conservation Group, which is campaigning against the project…said blasting the Mekong will destroy fish breeding grounds, disrupt migrating birds and cause increased water flow that will erode riverside farmland. Such opposition reflects a wider challenge to China's ambitious "One Belt, One Road" project to build a modern-day Silk Road through Asia to Europe.

Second Harbour Consultants, a subsidiary of state-owned behemoth China Communications Construction Corp (CCCC)…said it was surveying the Mekong for a report that China, Laos, Myanmar and Thailand would use to decide whether blasting should go ahead…The company said in an e-mail it had held meetings with local people "to communicate, build confidence and clear doubts." China's foreign ministry did not immediately respond to a request for comment…Despite reassurances from CCCC Second Harbour, some locals still believed the engineers were marking out areas for blasting, said Niwat…