Technical Information

Home > Technical Information > Measures Against Natural Disasters > Measure against high wave from typhoon

Measure against high wave from typhoon

A number of huge typhoons struck Kansai International Airport (KIX) in 2004. KIX endured storm surges that were the highest ever recorded in the 26 year history of observations at KIX. The waves that went over the seawalls washed out roads inside the seawalls. Additionally, there is an urgent need to prepare for a South-East Sea/South Sea Earthquake, which is expected to occur within decades.

KIAC has successively built up the seawalls so that they can survive severe conditions. KIAC has raised the seawalls to a level that will prevent abnormally high waves from coming over. (The height of abnormally high waves is based on the highest sea level recorded in Osaka Bay history. The highest level of the sea is defined as the level which could occur once every 50 years due to a powerful typhoon, for example the second Muroto Typhoon, at high tide.)

Bulked up seawall
Bulked up Seawall
Bulk-up construction of the seawall
Bulk-up Construction of the Seawall
Bulked up seawall
Bulked up Seawall
Tsunami Countermeasures

A large earthquake called the "Tonankai/Nankai (South-East Sea/South Sea) Earthquake"* is expected to occur sometime in the near future. A tsunami resulting from this earthquake is predicted to be of limited size, because it would have to pass through the Kitan Straits and into Osaka Bay. Also, because the airport island is situated in a location where the sea bed is rather deep (approximately 20 m), it is not expected that any such tsunami would hit the island in the form of a wall of water; the estimated height of such a wave in the vicinity of KIX is only 1.5 m. Because of this, high tides present more of a problem at KIX than tsunamis. Consequently, the reinforcement of the sea wall in preparation for high tides provides even more safety against tsunamis.

* Tsunamis with a maximum height of 1.5 m were predicted by tsunami and flood simulation analysis for the expected South-East Sea/South Sea Earthquake conducted by the Office of Emergency Management, sponsored by Osaka Municipal Government, Osaka Prefectural Government, and Wakayama Prefectural Government (Yoshiaki Kawata, Director, Research Center for Disaster Reduction System, Disaster Prevention Research Institute, Kyoto University), published March 29, 2004.

Page top