جولائی 13, 2010
China’s polluted, drought-ridden Yellow River once struggled to reach the sea. Now the “mother river” is being restored to health, writes Jonathan Watts, but for many the benefits remain to be seen.
On one wall of the control centre, a mosaic of TV screens flickers back and forth between the latest satellite photographs and rainfall projections. On another, a huge screen tracks the entire length of the Yellow River – China’s second-longest waterway – with real-time data from dozens of monitoring stations showing flow speed, pollution levels and reservoir volumes.
The operation closely monitors the outflow volumes from each of the nine provinces that border China’s “mother river” and decides whether they are on course to meet monthly targets. A sophisticated set of river controls allows engineers to intervene by opening or closing a high-tech network of automated sluice gates and monitoring devices. This gives them remote control over almost all downstream diversions of the water for agriculture and industry along its 5,464-kilometre length.
The system also allows engineers to flush bad pollution spills through the system more quickly, which has contributed – along with economic, legal and policy changes – to the improvement in water quality and quantity on the main river.
Now Chinese hydroengineers are embarking on a plan to upgrade the “digital Yellow River” – what they contend is the world’s most advanced water-rationing system – to try to save one of the most overworked waterways on the planet from drought, pollution and the unsustainable demands of a surging economy.
The plan, which begins later this year, is a major enhancement of an already advanced management system that has helped to reverse the decline of the river over the past 10 years.
For most of the past 30 years, the Chinese government has focused on engineered solutions to the country’s water problems that increase supply. When water ran out or became polluted, they drilled deeper wells or built longer diversion channels to tap fresh resources.
But the Yellow River, which has been the main artery of Chinese civilisation for thousands of years, has shown the limitations of that approach and forced a different way of thinking that blends science, conservation, old-style communist centralised control and modern market cap-and-trade mechanisms.
The change is evident at the Yellow River Conservancy Commission (YRCC) in Zhengzhou, the command centre for the waterway’s managers.
In 1997, the Yellow River symbolised everything that was wrong with China’s environment: 40% of its waters were off the scale for pollution, and the lower reaches were so choked with sediment that the river bed stood several metres above the surrounding farmland, raising the risks of floods. But the biggest problem was seemingly terminal dormancy. The river was so overexploited that it failed to reach the sea for 226 days a year.
Since then, however, the flow has been unbroken, and last year the basket-case river became an award-winning model when the YRCC won the Lee Kwan Yu Water prize in Singapore. Its head, Li Guoying, was promoted to national vice-minister for water resources. Its digital control system is now being emulated on other stressed rivers, including the Talimu in Xinjiang, the Hei in Qinghai and the Dong in Guangdong.
The European Union, which has a team working with the commission, said the award was well deserved.
“It’s an achievement. The water runs to the sea again,” said Paul van Meel, team leader on the EU-China River Basin Management Programme. “This is thanks to the central control. This is a unique way to manage a river on such a large scale.”
Leading conservationists, including formerly fierce critics of the Yellow River’s management, have also lauded the improvement, though they emphasise that more needs to be done.
“I appreciate the change of mindset of the Yellow River commission from conquering nature to promoting the healthy life of the river. The digital centralised control is a wonder,” said Ma Jun, founder of the Institute for Public and Environmental Affairs. “But the river is far from being revived. By keeping a minimum flow, we keep it from dying. But its once vibrant and rich ecosystem is damaged by the construction of cascade dams and the ensuing overexploitation of resources, and increasingly by water pollution.”
The main outstanding challenge is enforcing the fair distribution of scarce water resources among the nine provinces that share the river. Allocations can make the difference between wealth and poverty. This is evident at Liang village in Henan province. Although the cornfields here are just 10 kilometres from the Yellow River and Xiaolangdi reservoir – one of China’s biggest – they are drying up because the farmers have almost no water-use rights. Utterly dependent on rainfall for irrigation, the villagers are impoverished and insecure. This year, they are suffering from the worst drought in decades, which may well ruin the summer crop. But Henan has used its quota elsewhere.
“We have asked the government for help but they say there is a scarcity even of drinking water for the cities, so they cannot spare anything for our crops,” said the deputy head of the village, Lu Kasheng. “We have drawn up plans to drill a 400-metre well but it will cost 700,000 yuan [nearly US$110,000], so we need financial help as well as approval from the government.” The villagers get drinking water for only a few hours every two days.
Proportions for the provinces have been fixed since 1987, based on the average annual run-off between 1919 and 1975 of 58 billion cubic metres. That has proved woefully optimistic. Due to the damming of tributaries, the spread of cities and climate change, the volume slumped last year to 46 billion cubic metres. Provinces are supposed to equally share the shortfall. Yet the upstream regions of Ningxia and Inner Mongolia take more than one billion cubic metres of water above allocation every year.
The losers are groundwater supplies and ecosystems, particularly wetlands. Twenty-one billion cubic metres are supposed to be set aside for sediment flushing and maintenance of non-human life on the river. But this is the area of the water budget that is raided when provinces go over their limit.
This will be partly addressed later this year when engineers begin installing the second stage of the project, which will force recalcitrant upstream provinces to cede control over water-diversion sluice gates. The new system is currently being designed by the commission and Tsinghua University.
Once it is completed three years from now, the engineers in Zhengzhou say they will have remote control over 90% of the river’s taps for agriculture and industry.
“We are trying to resolve the contradictions between the provinces by coordinating water use,” says Pei Yong, director of the water regulation division. “This aims to ensure there is no break in the middle reaches, so water can flow to the sea and the ecology can be improved.”
While this centralised control system might seem a typically communist response to the water crisis, local governments in Ningxia and Inner Mongolia are also experimenting with market-based solutions, notably the trading of water-use rights. In provinces that have already used up their quota, industries can only expand their water use by paying farmers to improve irrigation efficiency. The offsetting is similar to the cap-and-trade system for carbon-dioxide emissions.
There are other signs that China’s mandarins are looking more closely at improving efficiency and limiting demand in some areas. In its agenda-setting “No 1 document” this year, the government made water conservation a priority, capping annual water consumption at 670 billion cubic metres and promising to spend four trillion yuan [about US$620 billion] on projects to reduce waste and enhance irrigation.
But there is still a long way to go before the Yellow River is off life-support. Hydroelectric dams remain outside the central control system. Demand for water in northern China continues to grow faster than efficiency gains. As a result, environmental pressure has shifted from the Yellow River to its tributaries, which are increasingly polluted, and underground aquifers, which are diminishing at an alarming rate.
The state also remains committed to environmentally disruptive megaprojects to boost supply. Its “ultimate solution” to the drought problems in the Yellow basin is the South-North Water Diversion – the world’s biggest hydroengineering project. Once completed, the planned western leg of the scheme will tap water from high on the Tibetan Plateauto replenish the Yellow close to its source. This will be technically difficult, politically controversial and hugely expensive, but if China is to continue to expand its economy, hydroengineers say there is no choice.
“The water shortages along the Yellow River are still a problem. The imbalance between supply and demand will become more and more serious unless we can divert water from outside,” says Pei. “For now, we will strengthen conservation and adjust the water-use structure. But the ultimate solution is diversion. If that does not go ahead, we will face a big problem in our water supply.”
The good news of the Yellow River goes only so far.
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