Last month, the Executive Yuan released its first set of data on soil liquefaction in eight administrative districts. The speed at which this information was made available, and the fact that it is incomplete, covering as it does only some administrative districts, suggests that this is preliminary data released because of a policy directive.
As such, it would surely cause a degree of confusion in wider society, as people misinterpret the implications of the information therein. It is concerning that the government, in an attempt to curtail public panic over the issue, is placing undue emphasis on our ability to find a solution to the problem through engineering alone. This would affect future national spatial planning going forward and be detrimental to sustainable development in Taiwan.
Soil liquefaction was first recognized as an important issue because of two earthquakes in 1964, one in Alaska and the other in Japan’s Niigata Prefecture. Taiwan also saw significant soil liquefaction in Taichung’s Wufong District (霧峰) and in Changhua and Nantou counties during the 921 Earthquake in 1999. Compared with the issue of structural safety in buildings, soil liquefaction is relatively poorly understood. However, while soil liquefaction results in fewer fatalities, it can cause significant damage to buildings and infrastructure.
The collapse of the Tainan apartment building — the biggest source of fatalities in the earthquake that struck southern Taiwan on the eve of this year’s Lunar New Year holiday — was mainly caused by the structurally unsound buildings in the area. It was not the result of soil liquefaction. Therefore, all we have to do is revisit the structural design, implement better construction quality control, and it should be possible to rebuild on the original site, this time with earthquake-proof structures.
This is a good approach, but will not work in areas prone to soil liquefaction. In Tainan, Annan District (安南) along the coast is such an area. Here, it would be necessary to reinforce the roads and infrastructure as a whole within the area.
Earthquakes do most damage by fault rupture or structural instability in individual buildings. In this regard, soil liquefaction is less important. Some natural ecological issues we can do something about, some we cannot. Much depends on the local circumstances. We can also try to improve the systems in place and raise engineering standards.
Natural ecological conditions, such as fault lines and areas prone to soil liquefaction, involve natural materials beneath the surface, such as soil or rock, and these differ region to region, hence the need for surveys and analysis by geological bodies. However, the results of these surveys should only be announced after they have been correctly processed, so that they can then be used for reference in the development of national spatial planning, and implemented within the framework of the National Land Use Planning Act (國土計畫法). Only then can we use our resources in the most efficient way possible.
We know from what happened during the 921 Earthquake that roads in areas surrounding those places where soil liquefaction occurred are also prone to a certain degree of damage. Although it is possible to reinforce this soil to protect individual buildings in those vulnerable areas, the question is whether the government is willing to invest in this infrastructure. That is, on the national spatial planning level, the government must review the situation from the perspective of the overall national finances and regional political and economic development, and devise a robust and reasonable national plan, region by region.
For the developed regions identified in the report as being areas of potential soil liquefaction, the government must take into account the facts about the existing buildings and how densely the area has been developed, and come up with a plan to either reinforce or relocate these buildings.
The best place to start would be with relatively undeveloped areas with a high risk of soil liquefaction. One option would be to reinforce the soil foundations of public construction projects.
This would place the emphasis on urban renewal earthquake resistance engineering projects, with a view to increasing capacity in those areas, allowing increased population density and levels of development in locations more at risk than surrounding areas. However, there are other options.
If it is a case of buildings deemed to be structurally unstable, or examples of shoddy construction, such as the so-called sea-sand buildings, then another approach would be urban renewal concentrating on earthquake-proofing, constructing new buildings on the original site, as long as the local traffic routes would not be adversely affected as a result.
Areas of potential soil liquefaction are geologically sensitive areas in which there is a possibility of geological disasters occurring, irrespective of the scale of any damage. The best solution would be to avoid developing these areas, or reducing the degree of development as much as possible.
According to the rankings of vulnerable areas in the Executive Yuan report, Taoyuan is at the third level. That is, it is an area with the lowest possibility of soil liquefaction. This, coupled with the presence of a hard red clay gravel layer basin that does not amplify earthquake waves, and the fact that it does not pass through an active fault, means that it is geologically sound. This would translate into lower development costs.
Taoyuan — in terms of national spatial planning and sustainable development — is the best option for the future political and economic development of the population of the Greater Taipei region.
Johnson Kung is director of the Taoyuan Department of Public Works.
Translated by Paul Cooper
Could Asia be on the verge of a new wave of nuclear proliferation? A look back at the early history of the North Atlantic Treaty Organization (NATO), which recently celebrated its 75th anniversary, illuminates some reasons for concern in the Indo-Pacific today. US Secretary of Defense Lloyd Austin recently described NATO as “the most powerful and successful alliance in history,” but the organization’s early years were not without challenges. At its inception, the signing of the North Atlantic Treaty marked a sea change in American strategic thinking. The United States had been intent on withdrawing from Europe in the years following
My wife and I spent the week in the interior of Taiwan where Shuyuan spent her childhood. In that town there is a street that functions as an open farmer’s market. Walk along that street, as Shuyuan did yesterday, and it is next to impossible to come home empty-handed. Some mangoes that looked vaguely like others we had seen around here ended up on our table. Shuyuan told how she had bought them from a little old farmer woman from the countryside who said the mangoes were from a very old tree she had on her property. The big surprise
The issue of China’s overcapacity has drawn greater global attention recently, with US Secretary of the Treasury Janet Yellen urging Beijing to address its excess production in key industries during her visit to China last week. Meanwhile in Brussels, European Commission President Ursula von der Leyen last week said that Europe must have a tough talk with China on its perceived overcapacity and unfair trade practices. The remarks by Yellen and Von der Leyen come as China’s economy is undergoing a painful transition. Beijing is trying to steer the world’s second-largest economy out of a COVID-19 slump, the property crisis and
As former president Ma Ying-jeou (馬英九) wrapped up his visit to the People’s Republic of China, he received his share of attention. Certainly, the trip must be seen within the full context of Ma’s life, that is, his eight-year presidency, the Sunflower movement and his failed Economic Cooperation Framework Agreement, as well as his eight years as Taipei mayor with its posturing, accusations of money laundering, and ups and downs. Through all that, basic questions stand out: “What drives Ma? What is his end game?” Having observed and commented on Ma for decades, it is all ironically reminiscent of former US president Harry