Environmental ombudsmen of the central authorities reported on Dec 1 that three artificial lakes covering a total area of about 150 hectares in a scenic zone in Zhangye, Northwest China's Gansu province, had not obtained approval from the higher authorities before being constructed by the local government in 2011.

The lakes, which have become a must-see for visitors to Zhangye, are now located in the center of the scenic zone that has gradually formed around them, which attracts not only large numbers of waterfowl and migratory birds, but also tourists. The scenic zone is one of the largest public parks in the city, which is home to 1.12 million residents. Its environmental and social benefits to the city have left local residents in no doubt that they were a worthwhile investment.

Despite this, what raised the eyebrows of the inspectors is that if a larger region beyond the city is taken into consideration, the three sizable lakes seem a little incompatible with the regional environment because they consume large amounts of water every year. Zhangye has a temperate arid climate, with annual precipitation of only 100-250 millimeters, but the annual evaporation is as high as 1,400-2,700 mm. That's why the municipal authorities jumped the gun in their construction in a bid to justify the means with the ends.

The three lakes are located in the center of the Hexi Corridor at the foot of the snow-capped Qilian Mountain Range, which stretches across 350 kilometers of the northeastern border of the Qinghai-Tibet Plateau. It is the snow melt water from Qilian that constitutes the main water body of the three lakes, about 4.65 million tons in total. The only river flowing into them is the Heishui River, a "mother river" of Northwest China that originates from Qilian and stretches 173 km to pour into a group of desert lakes in the Inner Mongolia autonomous region.

These desert lakes had dried up for decades before the central authorities instructed Zhangye to reduce its share of water taken from the Heishui River from about 20 years ago. It was also from that time when the melting of the snow in Qilian started accelerating remarkably due to climate change, which turned the narrow and quiet Heishui River into a wide river with enlarged floodplains.

It was against that backdrop that Zhangye built the three lakes, along with some other smaller ones, to make the best use of the valuable water resources. Local residents argue that as long as the desert lakes are maintained at their current size, Zhangye, which is located in the middle reach of the river, has enough reasons to make good use of the surplus water that would otherwise evaporate into the air.

What deserves more attention from the central authorities is that the snow caps on Qilian are projected to disappear in less than five decades at their current melt rate. That means none of the lakes today will survive after that if no new water sources can be found. There is no lack of ruins of ancient cities scattered all over the Hexi Corridor and beyond that tell stories of how the changing climate and water conditions impacted human activities in the vulnerable narrow valley that served as a key section of the ancient Silk Road.

It is imperative to prepare for the nature's coming red light rather than dwelling on the absence of a green light to a project concluded 12 years back.