Written by Darrin Magee.
By some measures, China is not a water-scarce country. Per capita water resources stood at just over 2,000 cubic meters in 2013 according to the National Bureau of Statistics, with overall water availability at nearly 2.8 trillion cubic meters. Yet these figures tell only part of the story. China’s seemingly sufficient water resources are severely polluted, unevenly distributed in space and time, inefficiently utilized, and increasingly diverted away from agriculture toward higher-value-added uses. Moreover, as the Chinese government moves forward on a path toward less reliance on carbon-based energy sources and greater use of non-hydro renewables like solar and wind, hydropower will almost certainly gain importance as a dispatchable electricity generation source that can balance the intermittent nature of solar and wind. Some of that hydropower will be developed on transboundary rivers in China’s southwest, further raising tensions with downstream neighbors already wary of China’s intentions.
To what extent do these factors – distribution, quality, and competing uses – contribute to China’s domestic water insecurity or to regional water insecurity between China and its neighbours?
Unevenness of water resource availability across space and time on a continent-sized country such as China confounds national averages that suggest relative water abundance. Waterways in the rainy south and southeast account for some 80% of the entire country’s runoff, compared to less than 5% for waterways in the arid northwest. To be sure, population densities are also greater in the southeast, but as central authorities seek to promote industrial development and large-scale urbanization in the drier western interior, strains on water resources will likely grow. Large variations in seasonal water availability also present challenges: summer monsoons can bring severe flooding, while dry winters can reduce rivers to a trickle. Record floods in 2010 and 2012 pushed the flood-control capacity of the Three Gorges Dam to its limits, killing hundreds of people, costing billions of Yuan, and washing untold amounts of precious topsoil into the sea. Meanwhile, record droughts gripped areas the size of European countries in southwestern China at great cost to agricultural output, spurring the usual calls to build more supply, storage, and diversion infrastructure such as dams on the Lancang (upper Mekong) and inter-basin transfers, but little in the way of increasing efficiency of water use.
The Ministry of Water Resources ranks China’s water sources on a quality scale ranging from Grade I (highest quality, available only in the remote headwaters of rivers) to Grade V. The scale, spelled out in GB 3838-2002, was last updated in 2002. Since then, tellingly, the use of Grade V+ (尖V类) has become commonplace to characterize water that is literally “off the charts” poor in quality. The chart below shows percentages of water attaining different quality grades in monitored lakes, wells, reservoirs, and river reaches, as reported in the most recent China Water Resources Report (2012). River water quality was surprisingly good, likely due to the large runoff volumes in southern China that reinforce the view that “the solution to pollution is dilution.” Particularly worrisome are the data for groundwater and lakes, especially as an increasing percentage of the rural and farming population turns to groundwater wells for drinking water and irrigation.
The increasingly clear linkages between energy and water also suggest a trend of growing pressure on China’s freshwater resources. At its simplest, the so-called water-energy nexus concept acknowledges that it takes energy to produce water (e.g., treatment and distribution), and water to produce energy (e.g., refining and transforming). In a very real way, the degree to which China’s leaders successfully address water security will have a direct impact on the country’s energy security as well, a second key priority of the leadership. While the mechanisms and potential efficiency gains of thermal electricity and hydroelectricity production are well understood, less so are the impacts that China’s laudable push toward renewable electricity sources such as solar and wind. These two resources, the development of which will likely be constrained only by available land, could eventually reach several thousand gigawatts of installed capacity (compared to China’s approximate installed capacity of 1000 GW in all generation sources at present).
China is also relatively inefficient in its water use across all sectors. A McKinsey study published in 2010 projected the gap between supply and demand to reach 2001 billion cubic meters by 2030, roughly 7% of the country’s total water in 2013. While 7% may seem a relatively small figure, poor water quality will remain a challenge for much of the water, both surface- and groundwater, that is available. At present, agriculture is responsible for roughly 50% of total water demand in China, so even though the study predicts agricultural demand to grow much more slowly than industrial and municipal demand (0.6% vs 3% per annum), agriculture will still account for roughly 420 billion cubic meters in 2030 if efficiency gains continue to be only incremental. Currently available and affordable efficiency measures such as drip irrigation, irrigation scheduling, gray water reuse, and greater reliance on low-water, drought-resistant crops could cost-effectively reduce much of that demand. Similarly, gains in municipal and industrial efficiency in areas such as thermal power generation and municipal supply could help close supply-demand gaps (current and projected, temporal and geographic) in a more equitable manner that reduces the possibility for social unrest or economic disruption.
The actual output of all that renewable capacity, however, will be far lower than a comparable capacity of thermal power stations (e.g., coal or nuclear) due simply to the variability of wind and sunshine compared to the ability of a thermal power plant to run at or near full capacity for 80% of the time or more. Hydropower, thanks to its ability to go from zero to full output in a matter of minutes or even seconds (i.e., its fast ramp rate) is a prime candidate for evening out the inherently uneven and less predictable output of solar and wind power. This means, then, that the already strong hydropower imperative that has for the past two decades sought to transform southwestern China’s great rivers such as the Lancang (Mekong), Nu (Salween), and Jinsha (Yangtze) into great power generators, will likely gain even greater momentum under an energy regime premised on massive-scale deployment of wind and solar. How those hydroelectric power plants are operated, in turn, will have a direct impact on the timing and quantities of water available downstream, the severity of negative impacts such as bank erosion and flash floods, and the likelihood of geopolitical tensions between China and its downstream neighbors.
While space precludes examining a more comprehensive definition of water security here, two indicators – reliable access to sufficient clean fresh water, and lack of domestic and international conflict over water resources – seem to be reasonable indicators. Quality and quantity are intricately linked, and the ancient mariner’s lament of “Water, water everywhere, nor any drop to drink” is reflected in the Chinese term “quality-induced scarcity” (水质性缺水), now unfortunately commonplace. China’s central leaders seem increasingly aware that their ability to retain a modicum of legitimacy through which to rule depends not only on continued economic growth, but also on social stability. For half-a-billion or so Chinese farmers, in turn, social stability depends in large part on their access to clean irrigation water and fertile, unpolluted soil.
Likewise, an increasingly large and vocal urban middle-class expects livable cities with reliable drinking water and breathable air. Water infrastructure projects such as dam cascades and the South-North Water Diversion may go some distance toward addressing uneven distribution of water over time and space, but not without social and ecological costs such as resettlement and habitat fragmentation, all of which have been clearly documented in countless cases around the world.
Discussions of water security must examine not only what constitutes security, but also whose security is at issue: That of non-human species and ecosystems? China’s farmers? Its urban middle class? The Party leadership? According to legend, the Great Yu brought peace and prosperity to early China by controlling flooding in what we now know as Sichuan. Satisfying competing needs for clean fresh water in a fashion that is socially equitable, ecologically sound, and technically feasible will be among the top domestic security challenges for China’s leadership in the coming decades.
Darrin Magee is Associate Professor of Environmental Studies, Director of HWS Asian Environmental Studies Initiative and Chair of Asian Studies Department. Image credit: CC by Asian Development Bank/Flickr