China will ramp up construction of dams, reservoirs and wells in response to a severe drought in the country’s south-west, but the move is likely to raise tensions with downstream countries, which have already blamed reduced river flows on Beijing. Most of south-west China has been affected by the drought, which began in November and has left more than 24m people without adequate access to drinking water. Downstream in Thailand, cargo boats have been stranded along the banks of the Mekong, which is at its lowest level in half a century, while fishermen complain of empty nets. Beijing has launched...