The An­keng area, on the left bank of the Xin­dian River in New Tai­pei City, has experienced a building boom in recent years and a great influx of population. Traffic on its roads is growing. With the greater vibrational stress caused by all the building and traffic, the water mains under the roads are experiencing increasingly serious leaks.

Looking for leaks, an engineer uses an acoustic leak detection device to search for the sound of water.

In order to improve the leak situation in An­keng, after Chinese New Year’s the Tai­pei Water Department kicked off a process to extensively replace the area’s water distribution lines. In particular, under main routes such as An­kang Road the old cast-iron mains that are highly susceptible to rust are being replaced with ductile iron pipes that are resistant to earthquakes and vibrational impacts in general.

Before the newly laid mains are covered with earth, the installation crews cover them in plastic wrapping.

“This is a trick we learned from the Japanese,” says Xu Min­neng, the head of leak prevention for the Tai­pei Water Department. “Just a simple plastic covering can keep the pipes separated from corrosive agents in the soil and greatly reduce the dangers of rusting and deterioration, thus extending the life of the line.”

As for the water distribution lines that connect to households, Japanese-developed corrugated stainless steel tubing is replacing conventional stainless steel pipes.

Frankie Chen, chief engineer at the Tai­pei Water Department, explains that the corrugated pipe can be bent as needed for installation, obviating the need for the joints and couplings that in the past have been a major source of leaks. This greatly reduces the system’s vulnerability to seismic damage.

“Japan has a high population density and frequent earthquakes. It’s an environment similar to Taiwan’s. Their experience with leak prevention provides some very useful lessons for us,” says Chen.

In fact, Japan is the acknowledged global leader for the efficiency of its water distribution systems. Tokyo, with a leakage rate of around 3%, is regarded as a model for water resource management.

In Taiwan, on the other hand, the leakage rate is over 19%, and in Keelung and Taichung, the cities with water infrastructure that is in the worst shape, it can reach a staggeringly high 30%.

In reality, the problem of leaks has long been a major problem for most modern water systems. Chen Fu-tien, the Taiwan Water Corporation’s president, explains that apart from the age of the infrastructure causing leaks, people can add to the damage with greater transportation loads and building projects.

The environmental characteristics of Taiwan, including frequent earthquakes and extreme topography, add to the rate of water mains deterioration. For instance, water mains in Tai­chung and Nan­tou were damaged 14 years ago during the 921 earthquake, with the result that leakage rates in those areas have remained persistently high.

Keelung, 80% of which is mountainous, relies on more than 10 water pumping stations to overcome the inherent difficulties in delivering water to homes high on slopes. The resulting excessive pressure increases damage to water lines.

Since Japan has natural conditions that are very similar to Taiwan’s, how has Tokyo been able to reduce leaks to about 3%?

At the end of World War II in 1945, the infrastructure of Tokyo badly needed attention, and the water system’s leakage rate stood as high as 80%. To give the people of Tokyo a stable water supply, water resource agencies embarked on water system surveys and improvements. In the 1960s, Tokyo replaced its water mains with longer-lasting ductile iron pipes. And in the 1980s it began to put in corrugated stainless steel tubing when replacing the smaller lines delivering water to end users.

According to an ROC Control Yuan report, from 1950 to 2000 Tokyo invested NT$672 billion all told in preventing leaks. That’s what brought the rate of leakage down. It cost a staggering average of NT$29.5 billion for every percentage point of leaks reduced.

In comparison to Japan, which got serious about tackling these leaks as early as the 1950s, Taiwan didn’t start showing real concern about the problem of leaks until 2002.

Frankie Chen of the Tai­pei Water Department points out that early on it was clear that Taiwan’s water supply infrastructure was inadequate. In order to meet the demand for water that rose in step with economic development, the department as well as the Taiwan Water Corporation invested large amounts of resources in water treatment facilities and water distribution lines.

In 2002, Taiwan hit a severe drought when almost no rain fell for half a year. It was only then that water resource agencies on the island became aware of the seriousness of the problem: the rate of leakage in Tai­pei City stood at 28.43%, and other localities had leakage rates near 25%.

“Taiwan, which lacks water, simply can’t afford the luxury of wasting one-fourth of its water resources!” Facing a wave of criticism, water resource agencies began to actively work on preventing leaks. The Tai­pei Water Department in 2006 drafted a 20-year long-term line replacement plan aimed at bringing leaks under 10% by 2025 at a total cost of NT$23 billion.

Furthermore, the Taiwan Water Corporation, which has a wider scope of responsibilities, back in 2004–2012 invested NT$39.5 billion and was able to bring down leakage in other cities and counties to 19.55%. In the coming decade, it plans to spend NT$64.5 billion with the goal of bringing down leakage to 14.25% by 2022.

Taiwan and Japan have long had friendly relations, and over the past decade or so water resource agencies in the two countries have had several exchanges of technology and experience relating to leak prevention. The approach that Japan takes of intensively testing for leaks in one small area at a time has become the model adopted for leak management in Taiwan.

Chen explains that after replacing lines, they turn off all the supply connections to an area of a few blocks except one, where a large water meter is installed. They then measure how much water enters the area and how much gets to end users to determine how effective the improvements have been.

There are plans to divide Tai­pei City into 850 water distribution areas, and the island of Taiwan as a whole into more than 4300. The areas with high leakage rates and high danger of water shortages are being repaired first. Kee­lung, Tai­chung, and the old Tai­pei neighborhoods of Wan­hua and Da­tong are among the places that are currently focuses of leakage repair and prevention efforts.

In the middle of April Atsu­shi Ma­suko, head of the Tokyo Metropolitan Bureau of Waterworks, came to Taiwan to sign a memorandum of understanding with the Taiwan Water Corporation and the Tai­pei Water Department. In the future the two sides will engage in exchanges of technology and experience with regard to leak prevention, earthquake protection, water treatment management and personnel training.

Chen Fu-tien, Taiwan Water’s president, points out that after the earthquake and tsunami that struck Japan on March 11, 2011, all quarters of Japanese society were greatly moved by the spirit of brotherhood demonstrated by the generous relief donations from Taiwan. The resulting goodwill toward Taiwan helped to facilitate this instance of formal cooperation.

From water line replacement and leak prevention techniques to construction, Taiwan has been learning from Japan for over 10 years now, and its leakage situation has been improving. Catching leaks, however costly and time-consuming, is important work in a place like Taiwan where water resources are limited. Every drop counts.