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Taiwan's Climatic Extremes

Fatal Water

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With the arrival of Typhoon Morakot, Taiwan suddenly swung from drought to flooding. How are the woes of water altering life in Taiwan, and what can Taiwan do about it?

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Fatal Water

By Fuyuan Hsiao, research by Jerry Lai, Ming-Ling Hsieh
From CommonWealth Magazine (vol. 428 )

A typhoon that arrived from Taiwan's east turned the most severe drought in the past seven years into the worst flood in the last half-century.

Dozens of towns in southern Taiwan – throughout the counties of Tainan, Jiayi, Kaohsiung, Pingdong and Taidong – were affected by the flooding, which covered 26 percent of the island's total land area. Southern Taiwan appeared to be a lone boat foundering in a vast ocean.

It was a great irony that one natural disaster (drought) needed to be relieved by another and that the driest part of the country – southern Taiwan – was the hardest hit by the storm. And yet, despite the staggering amount of precipitation that fell, if Taiwan faces high temperatures in the next three months and no more typhoons hit its shores, the country could face another bout with drought early next year.

Three days before Typhoon Morakot pummeled Taiwan, Shaw C. Liu, director of Academia Sinica's Research Center for Environmental Changes, predicted in an interview with CommonWealth Magazine that Morakot's rains would be extremely heavy. With Taiwan's large climatic swings and the warming of the seas around the island, typhoons are now absorbing even more moisture than usual and pelting Taiwan with shocking amounts of rain.

Chung-Ming Liu, the director of National Taiwan University's Global Change Research Center who has followed climate change for more than 20 years, says the danger of climate change is not just that climates will become extreme, but that they will also change extremely quickly.

Not long ago, climate scholars predicted that Taiwan was entering a decade of drought, and that in the next 40 years, it could face desertification. Within 24 hours, the idea that Taiwan could face water shortages became a joke.

But is it really true that Taiwan does not lack water? Instead of tempting fate and depending on typhoons to solve drought crises, can Taiwan rely on effective management to develop a more consistent water supply? As a country with one of the highest levels of precipitation in the world, why does Taiwan even face water shortages?

Water Crisis Getting Worse

Nobody is more sensitive to the problem of an unstable water supply than Taiwan Water Corporation vice president Nan-Jer Hu. At the beginning of April, Hu was already in a terrible fix.

Five meetings on the looming drought had already been convened, with each meeting more worrying than the one before it.

Just after the water company announced in early August that a second phase of water rationing was imminent, a typhoon warning was issued that eased Hu's sense of crisis, but his anxiety shifted to the other extreme – from the dilemma of too little water to the quandary of too much. Having worked at Taiwan Water Corp. for 20 years, Hu has gradually accepted that his worries over drought conditions will resurface once every two or three years.

The drama of rapidly alternating droughts and floods has been repeatedly enacted in Taiwan in recent years. Drought has followed flooding at least five times in the past ten years (see table), and the dual problem of controlling floods while preventing water shortages has become Taiwan's most serious challenge.

Water has already become the planet's most important strategic asset. Suddenly, this essential resource no longer appears to be inexhaustible, but is in fact in finite supply. A number of governments are gradually expanding their attention from CO2 to H2O, and the United Nations, in its World Water Development Report released in March, warned that the global water crisis is growing more severe by the day, and almost half the world's population will be living in areas of high water stress by 2030.

Taiwan is not immune to the trend.

The Decade of Drought Has Begun

Taiwan's average annual precipitation is nearly 2.5 times the world average. The country gets 90 billion cubic meters of rainfall per year, enough to fill its more than 40 reservoirs 45 times. So why does it go through periods when it lacks water?

The crux of the problem is not the quantity of rainfall but its uneven distribution.

Chung-Ho Wang, a research fellow in Academia Sinica's Institute of Earth Sciences who has long studied rainfall trends, says northern Taiwan gets more rainfall (an average of 2,800mm per year) than the south (an average of 2,200mm per year). Over the past 10 years, southern Taiwan has always been dry in the spring, because 90 percent of its rainfall comes between May and August. Once the rainy season ends, a long dry spell sets in.

Wang observes that over the past 60 years, precipitation has declined in three-quarters of Taiwan's land area, and in southern Taiwan the number of rainy days per year has fallen from 195 in the past to only 130 at present.

"Taiwan has already entered a 10-year cycle of drought," Wang asserts, pointing to a rainfall map of Taiwan on his computer.

The 2009 UN World Water Development Report, titled "Water in a Changing World," contends that the greatest threat to the world's water supply is poor governance, which causes water resources to be used excessively and incorrectly. Taiwan is guilty on both counts.

Water Resources Agency director-general Shen Hsien Chen acknowledges that water usage considerations in government policy need to be adjusted. In the past, whenever a water-using entity made a request, the agency would comply without a second thought. But today, water supply policies should change course, Chen argues, with a fixed supply dictating demand. Those who want water should be required to solve the problem themselves.

Among those who have done just that are the Formosa Plastics Group (to meet the needs of its sixth-naphtha cracker expansion project) and the Taoyuan High-Tech Industrial Park. Both built seawater desalination plants to meet their water needs and gain government approval for their projects.

Leaky Water Pipes

Other important governance flaws are poor reservoir management and leaky water supply pipes.

Academia Sinica's Liu says that in the past, rainwater would remain in the soil for two days before being discharged into the ocean. But as Taiwan has become more urbanized, Taiwan's soil has become less able to absorb water, and rainwater now flows into the ocean after just two hours. Thus, the country has become even more dependent on reservoirs to store water.

The only problem is that the capacity of Taiwan's reservoirs is limited. They are only able to store a total of 2 billion cubic meters of water, and in order to meet water demand, must be replenished three times a year (five times a year for Shimen Reservoir in northern Taiwan). When too few typhoons deliver too little rainfall or when they do not arrive at wide enough intervals, water supply becomes problematic. Exacerbating the challenge is the major build-up of silt in Taiwan's reservoirs, which steals away an average of 22 percent of their capacity. In other words, simply relying on reservoirs will not satisfy Taiwan's long-term water resource needs.

Another long-tolerated management oversight is Taiwan's leaky water pipes.

More than 22 percent of the water piped around Taiwan leaks away, higher than the world average of 18 percent (Japan's rate is only 7 percent). Aside from being wasteful, the leakage problem creates unnecessary economic losses. In the case of Taiwan Water Corp., its revenue totaled NT$26.7 billion in 2008, while it watched NT$7.4 billion worth of water seep away. Saving that money would have driven the company's net profit more than 100 times higher.

Taiwan Water's Hu admits that leaky pipes let billions of Taiwan dollars get away every year, but he maintains there is no way to efficiently solve the problem. According to International Water Association (IWA) standards, 1.5 percent of the total length of piping in a network should be replaced annually for water not to be wasted, but Taiwan barely meets that standard halfway, replacing only about 0.65 percent of its piping every year.

The Cabinet has noticed the embarrassingly high leakage rate, and will allocate NT$27.2 billion over the next four years to the water company to replace old pipes. But even with that investment, Taiwan's leakage rate will only improve to the world average.

Water Pricing: A Political Hot Potato

Another major issue authorities must contend with is the relatively cheap price of water in Taiwan. Among OECD and neighboring countries, Taiwan's average unit price of water is only higher than that in China and Korea. CommonWealth Magazine found, however, that measured in terms of national income, the price of water in Taiwan is only one-third that of China's. It has not been adjusted in 15 years, even though national income has grown 55 percent during that period.

The Water Resources Agency's Chen laments helplessly that water pricing is a political issue that nobody is willing to tackle. Water represents only 0.4 percent of an average family's expenses in Taiwan, far lower than the global average of 4 percent, and less than 1 percent of enterprises' operating costs. Such low prices provide little incentive to save water or develop a water conservancy industry.

That lack of environmental consciousness is reflected in water consumption. In Taiwan the average daily per capita water consumption for domestic purposes is 274 liters (350 liters in Taipei), 14 percent higher than the world average. Only 57 percent of water used in industry in Taiwan is recycled, compared to 90 percent in Japan and Germany.

Unpredictable Weather

The water delivered by Typhoon Morakot may have already made people forget that 2009 is destined to be an extremely dry year. The U.S.-based National Oceanic and Atmospheric Administration observed over a month ago that eastern equatorial Pacific sea surface temperatures were at least 1.0 degree Celsius above average and were continuing to rise, a sign that the El Nino climate phenomenon will return this year in the northern hemisphere and peak in winter. It is expected to bring drought, which will reduce harvests and drive up world grain prices.

As the planet's climate grows more extreme, the weather is more difficult to predict. National Taiwan University's Liu suggests that, rather than relying on nature, Taiwan's water policy should be reconsidered based on the idea of diversifying the country's water sources.

Taiwan's domestic, agricultural and industrial water users are all supplied from the same source, but the IWA has suggested the use of a dual piping network to separate potable water and reclaimed water or rainwater, which would reduce the pressure on potable water supplies.

"Taiwan's homes all seem like they're wearing raincoats, deflecting rain away. In the future, buildings will have to be like trees and store water," Liu explains. Building large-scale water recycling systems into big structures will not only lower the threat of water shortages but also reduce dependence on water reservoirs, and it is the cheapest solution to the problem.

"If there's no water, there's no future," says the Water Resources Agency's Chen, repeating the warning he heard over and over from experts at an international sustainable development forum in South Africa six years ago. The biggest challenges to human survival and the world's hottest flashpoints are all entangled with the issue of water.

This is the reality that Taiwanese people, who pay one-ninth of the price Germans do for water and use twice as much per capita, must confront. Taiwan constantly seesaws between the extremes of too much and too little water, and it no longer has any leeway to use water as extravagantly as it has in the past.

Translated from the Chinese by Luke Sabatier


Chinese Version: 要命的水

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