Dalai Lake is shrinking. For years, the water level of northern China’s largest freshwater lake – lying on the Hulunbuir grasslands of Inner Mongolia, close to the borders with Mongolia and Russia – has been falling. Since 2009, the local government has been trying to halt the decline by siphoning off water from the Argun River, which forms part of the boundary between Russia and China. But Dalai’s long-term future is still unclear.

Dalai is a huge body of water – the fifth biggest of China’s freshwater lakes. And its importance in maintaining the ecological balance of the Hulunbuir grasslands, currently the healthiest in China, has earned it the nickname “Kidney of the Grasslands”. In 1986, Inner Mongolia established the Dalai Lake Nature Reserve in order to protect the site’s rare birds, wetlands and grasslands ecology. In 1992, the area was upgraded to a national nature reserve and, in 2001, it was included on a list of internationally important wetlands.

But recognition has not prevented decline. “The water level drops every day. It hasn’t come back up for seven or eight years,” the 60-year-old owner of Golden Sands Holiday Village, a resort on the north-east bank of the lake, told me when I travelled to Hulunbuir in September last year. The grasslands were already yellowing and the herders were driving to and from their homes with loads of grass, harvested for winter fodder.

The owner of Golden Sands (who asked not to be identified by name) and his wife are not herders. They started their resort business 10 years ago. July and August is their busy period, when they offer tourists grassland experiences like swimming in the lake and fishing with rod or nets.

When I met the owner, it was clear weather, and he pointed out the white sands by the edge of the lake, explaining that the wind blows for four days out of every five. “As soon as the wind gets up, the air is filled with sand,” he said. He believes desertification of the grasslands is a direct result of the lake’s shrinking size.

Falling water levels have left a 600-metre wide stretch of white sand between the grasslands and the lake. According to media reports, satellite surveys calculated the area of the lake to be 2,370 square kilometres in April 2000. By June, 2010, it had shrunk to 1,850 square kilometres – a loss of 520 square kilometres.

Manzhouli, a border city north-west of the lake, once planned to use water from here to create its own manmade lake, with a “Lovers’ Island”, but it was forced to abandon the idea due to the falling water levels at Dalai.

The owner of Golden Sands blames the lake’s decline on years of unusually dry weather: “It doesn’t snow all summer, and then we get big snows in the spring – like this year. It gets so cold that even us locals can’t take it.”

Liu Songtao is deputy director of the Dalai Lake National Nature Reserve management bureau. He agreed that the shifting ecology of the grasslands and the lake is strongly affected by the climate, and that the dwindling size of the lake is due to sustained dry weather. 

The lake gets its water from the Kherlen and Wuerxun rivers, as well as from rain falling onto the lake and its surroundings. Liu said that temperatures on the grasslands have been rising for over 10 years, with annual average temperatures increasing by about three degrees Celsius between 1960 and 2009, while precipitation has fallen. The amount of water flowing in from the two rivers has also been decreasing. In 2007, none came through at all.

The falling water level has exacerbated the degradation of the grasslands. “There is a direct link between the worsening lake ecology and the degradation and desertification of the grasslands,” Yang Yusheng, a water engineer with Hulunbuir city, told the media last year. Yang said that falling water levels are causing groundwater from the surrounding area to flow inwards, lowering the level of groundwater under the grasslands and worsening desertification. “Dalai Lake is the kidney of the Hulunbuir grasslands – and of course you’re going to suffer if your kidney stops working.”

The effects of falling water levels are not only felt in China, but also in Mongolia and Russia. In 1994, the three nations established the Dauria International Protected Area, of which the Dalai National Nature Reserve is a member. In 2005, Mongolia formed plans to retain a tenth of the flow of the Kherlun River for development of its local mining industry. But, explained Liu, the project was abandoned after discussion between the three parties.

To halt Dalai’s decline, the city of Hulunbuir came up with a plan: it would take 1.05 billion cubic metres of water a year from the 3.7 billion that flow through the Hailar River (the upstream name of the Argun) to replenish the lake. China’s State Environmental Protection Agency (now the Ministry of Environmental Protection) approved the plan in April 2006 and, in the spring of 2007, work began.