Down river at its north-easterly end of the Liujiaxia reservoir, the terrain drops almost 3000 m from the headwaters of the Yellow River. Here along the river banks an agricultural village sits on a perfectly flat-topped peak, also known as tableland and described in Chinese as, ‘taidi.’ The Liujiaxia reservoir has the largest body of water in Gansu province and while its primary purpose is generating electricity, it is also used for flood control, irrigation and ice flood prevention. Irrigation plays a key role in China’s agriculture and food security. Irrigated land produces about 70% of the total grain, 80% of the cotton, and 90% of the vegetables and fruits, and accounts for 45% of the arable land in China. It has enabled a significantly higher crop yield in the main foodproducing regions like the North China Plain, where irrigated wheat yield is 70% higher than rain-fed wheat yield.