Osaka’s vulnerability to flooding is immense. Ninety percent of its urban area sits on flat lowlands. Rivers and the sea surround the city. This makes it extremely vulnerable to flooding. The Yodogawa River alone threatens sixteen wards. This is where the Nishi Osaka Flood Control Office’s work on the Naka-gawa River flood control project comes in.
The Naka-gawa River flood control project is vital to Osaka’s safety. The city is upgrading its sewage system to handle heavy rainfall. It can now manage up to 60 mm/h of rainwater. But imagine a south or southeast sea earthquake. Experts predict a 60% to 70% chance within the next 30 years. Such a quake would cause significant damage. Two- to three-meter high tsunamis would hit Osaka about two hours later. The Naka-gawa River flood control project helps mitigate these risks.
The project’s scope is vast. It includes improving river banks to prevent collapse. It also aims to enhance the drainage capacity of the city’s sewer system. This is crucial for inland flooding. Inland flooding occurs when rainfall exceeds the capacity of the sewers. Water then accumulates causing widespread damage. The project includes the construction and maintenance of seawalls. These seawalls are designed to protect the city from tsunamis. Currently the seawalls are being upgraded from 5.7 meters to 7.2 meters above the lowest water level. This height exceeds the 5.0 meters stipulated in the Tsunami Preparedness Plan.
The Naka-gawa River flood control project is more than just infrastructure. It’s about community preparedness. The city has created a Flood Disaster Prevention Map. This map shows areas vulnerable to flooding. It indicates evacuation routes and shelters. The project involves public awareness campaigns. These campaigns encourage residents to prepare emergency plans. This includes identifying flood risks and practicing evacuation procedures.
The project’s impact is significant. It reduces the risk of catastrophic flooding. It protects lives and property. It contributes to Osaka’s overall safety and resilience. The Naka-gawa River flood control project isn’t just a construction project. It’s an investment in Osaka’s future. It’s a testament to the city’s commitment to protecting its citizens. Standing here today you can appreciate the scale of the project. You can understand the dedication needed to safeguard a city prone to such extreme weather events. The Naka-gawa River flood control project is a silent guardian. It quietly works to protect Osaka from the destructive forces of nature.