Kansai International Airport (KIX) was opened in 1994 after more than 7 years of work. It is a modern engineering marvel, constructed mainly of glass and steel, and built entirely as an artificial island. It is considered as one of the greatest architectural feats of the late 20th century. While it has only one runway, another one is under construction at the moment.
Because the site is built on compacted fill, it suffers from subsidence. It sinks at 2-4 centimetres a year. The terminal is 1.7 kilometres long, and was designed by a world-famous Italian architect named Renzo Piano. KIX is linked to the mainland by a 3.7-kilometer bridge, serving the nearby cities of Osaka, Kobe, and Kyoto.
The airport is located just 15 feet above the sea level. Could it survive a tsunami scale disaster, similar to that one that struck off the west coast of Sumatra recently? Well, four months after opening, the airport was severely tested by the magnitude 6.7 Kobe earthquake; it survived with only minor damage. But that was only a 6.7 and not 8.3 Richter scale tsunami!
Was Kansai Airport an engineering mistake or Japan?s super structure of the new millennium? Well, the debate rages on as it starts to sink - albeit very, very slowly.
Defenders believe that it is an engineering marvel and expect it to succumb to gravity at an acceptable level, but critics say it is a waste of money. What?s more, the additional new runway under construction now would continue to cause the Airport to loose more money.
Some interesting facts here: Kansai was built over the sea at a depth of 17?18 meters (56 to 59 feet). Hong Kong?s Chek Lap Kok (CLK) was built on firmer seabed in far shallower waters and South Korea?s Incheon was constructed over water about 1-3 meters (3 to 10 feet) deep. Of these three, Hong Kong?s airport appears to be the best-engineered marine platform in the world and had hardly budged since 1998. Incheon?s expected subsidence is about 2.5 cms (one inch) over the next 20 years whereas Hong Kong?s CLK will have a sink rate of around 4 cms (1.6 inch) over the same period. Kansai? At 2-4 cms a year, in 20 years time, it may sink up to 40 to 80 cms (16 to 33 inches).
Don?t be alarmed! According to Naotoshi Takada, professor of soil engineering at Osaka City University, the airport was not going to sink completely into the ocean. There would be some fix up (hydraulic pillars that offer a kind of mechanical pillow to keep the terminal perfectly steady) and constant repairs on going. The slide into the mud was expected. In fact, they foresee it to sink before steadying. Anyhow, it would not pose any dangers to the operation of the airport nor to the passengers using it.
Kansai was originally planned as an alternative to the crowded Narita airport but the cost of operating there was rather expensive for many airlines. This has caused some major European and American carriers to stop their operation there, but other Asian carriers have more confidence with this island airport and have continued to increase their frequencies there.