Urban Risk and Well-being in Tokyo

According to UN-HABITAT, over half of the world’s population lives in urban areas, a number that will increase to nearly 70 per cent by 2050. Meanwhile, urban areas occupy just 5 per cent of the earth. Although high urban density can bring many benefits, it should not be forgotten that high population densities, and the resultant concentration of wealth in tiny spots around the globe, increases risk exposure to these places. In recent years, natural disasters have increased both in severity and frequency related to climate change, and cities not traditionally associated with such disasters are now facing increased risk. Simultaneously, because of densities of infrastructure that accompany rapid urbanisation, the complexity of disasters, such as the combination of floods, power plant or factory accidents and hazards, can be triggered by the same natural disaster. The application of new risk-management policies seems to be an urgent matter as cities accelerate their growth, and given the demographic momentum of an urban transition.

The Tokyo Metropolitan Area, composed of the capital city, Tokyo, and the surrounding three prefectures, is known as the largest metropolitan area in the world, with a population of 35 million and a GDP of US$1,479 billion. Although the historical cityscape was mostly demolished during World War II, the fundamental structure of Tokyo remained with its unique urban form centralised around the Imperial Palace. Modern infrastructure, such as railways and motorways, were transferred onto this urban form, and it is because of these systems that a huge number of people can live, move and work in Tokyo. Life expectancy at birth for males is 73 years and for females 78 years, which are among the highest figures in the world. The number of murders in Tokyo per million people in 2010 was 7.7, a very low rate among other global cities. With these facts in mind, Tokyo’s well-being could be measured as one of the highest in the world. Meanwhile, the city has been facing severe disasters like the Great Kanto earthquake that struck in 1923, as well as more routine typhoons and floods. There have been significant losses caused by these disasters; however, because of their consistency, risk-management policies have accumulated over time.

The complex disaster on 11 March 2011 caused by the earthquake in east Japan, and subsequently the tsunami and damage to the Fukushima nuclear plant, also had an effect on the city. In Tokyo, 400 kilometres (248 miles) away from the M9 earthquake, the shock was rated a 5+ out of a total of 7 under the measurement system used in Japan. And yet, only ten houses collapsed and seven people died. This seemingly limited amount of damage points to the massive set of improvements in the seismic performance of buildings that were put into place following the Great Hanshin-Awaji earthquake in 1995. Also, because of the ‘my-com-meter’, a system introduced post-1995 to shut down residential gas supply at the first sense of an earthquake, there were no fires in the city. Bridges, motorways and railways have also had considerable reinforcement over the past decade, and so were not seriously damaged. Tokyo in 2011 offers us some visible success of several risk-management policies that have been refined over the past century, and specifically within the past 15 years.

However, while no major infrastructural damage or large numbers of deaths occurred, Tokyoites still faced serious inconveniences, particularly those who rely on the highly developed urban infrastructure in the centre of the city.

The earthquake struck around 3pm. Since there was little damage to the city, people assumed that they would be able to get home as usual. Tokyo has one of the most sophisticated train systems in the world, moving some ten million people daily. However, following the quake, all the lines were systematically shut down in order to monitor for any possible damage. Some 40 per cent of the lines, mostly subways, recovered within the day. But the rest were kept shut until the following day. This unprecedented shut-down saw the city’s streets overflowing with people. Major terminals, such as Tokyo Station and Shinjuku Station, which usually accommodate more than 1.5 million passengers every day, closed. Consequently, people had to take what transport they could, with many walking for several hours back to their homes. Some bought and rode bicycles, others were picked up by car by a family member, still more went back to the office, or stayed at the refugee centres that were set up in the city’s public facilities and shopping centres. While things remained calm and organised, the lines of walking people did not disappear until the early morning. This experience made explicit the risks of a Metropolitan Region dependant on daily long-distance commuting.

The other inconvenience Tokyo faced was as a result of the impact of the tsunami on the nuclear plant at Fukushima. The plant shut down, creating electricity shortages, and resulting in reduced train frequency on each transit line and the closure of barrier-free transit infrastructure such as escalators and lifts. Because of these events, the mobility of elderly people and families with small children was significantly reduced. In response, the government ordered a reduction in domestic electricity use, which had the result of, among other things, decreased temperature control. Furthermore, because of the disaster, people began to stock up on supplies. In particular, people rushed to purchase bottled water, even though the official radiation levels in Tokyo’s water supply showed no signs of being harmful to humans. As a result there was less clean water available to those most vulnerable to radiation poisoning, such as infants. So, even though the infrastructure of the city survived, the social and economic materiality of city living was proven to be fragile, and with mobility and health vulnerabilities increased among the elderly and the young, many Tokyoites lost confidence in a city that traditionally has a very high quality of life.

Over the next few years, urban practitioners, disaster-management experts and risk-assessment professionals will actively be responding to the lessons learnt from the events of March 2011. For example, one outlier was Roppongi Hills, one of the recent major urban development projects in the heart of Tokyo. It was not affected by the disaster at all. During the shut-down of the city’s public infrastructures, it was able to offer support to people who were not able to go home by providing ample stocks of food, water and blankets. Shocks to the area’s high-rise buildings, such as the Mori Tower, were reduced by ‘Dumping Devices’, which meant that operations were back to usual the following day. Because the complex had its own LNG (liquefied natural gas) plant, it was free from the ensuing electricity shortage and was even able to provide electricity to the surrounding areas.

While Roppongi Hills can provide several best practice lessons, and is the largest private based development in Tokyo, it is a relatively small area compared to the whole Metropolitan Region. However, risk-management policies are now developing in order to implement the lessons learnt here, to Tokyo as a whole. Forecasts show that there is a 70 per cent chance of a great earthquake occurring in or near Tokyo within the next 30 years; therefore, just like after the earthquake in 1995, urban systems need to continue to implement risk-management policies.

Takayuki Kubo is an Architect and Senior Researcher of the Institute for Urban Strategies at The Mori Memorial Foundation.