Tourists watch water gushing out from the Xiaolangdi Reservoir on the Yellow River during a sand-washing operation in Luoyang, central China's Henan Province, July 23, 2013. The on-going operation works by discharging water at a volume of 2,000 cubic meters per second from the reservoir to clear up the sediment in the Yellow River , the country's second-longest waterway. Speeding currents would carry tons of sand into the sea. The Yellow River has been plagued by an increasing amount of mud and sand. Each year, the river bed rises as silt deposits build up, slowing the water flow in the lower reaches. (Xinhua/Zhang Xiaoli)