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Tokyo Preparing For Floods 'Beyond Anything We've Seen' (tampabay.com)
In the face of an era of extreme weather brought on by climate change, global cities are working to improve their defenses. The New York Times reports (Warning: may be paywalled; alternative source) of Tokyo's $2 billion underground anti-flood system that consists of tunnels that divert water away from the region's most vulnerable floodplains. The city is "preparing for flooding beyond anything we've seen," says Kuniharu Abe, head of the underground site. From the report: But even in Tokyo, the onset of more frequent and intense storms has forced officials to question whether the region's protections are strong enough, a concern that has become more urgent as the city prepares to host the 2020 Olympic Games. Across Japan, rainfall measuring more than 2 inches an hour has increased 30 percent over the past three decades, the Japan Meteorological Agency estimates. The frequency of rainfall of more than 3 inches an hour has jumped 70 percent. The agency attributes the increase of these intense rains to global warming, heralding a new era in a country that is among the world's wettest, with a language that has dozens of words for rain. [...]
Experts have also questioned the wisdom of erecting more concrete defenses in a country that has dammed most of its major river systems and fortified entire shorelines with breakwaters and concrete blocks. Some of these protections, they say, only encourage development in regions that could still be vulnerable to future flooding. In eastern Saitama, where the Kasukabe facility has done the most to reduce floods, local industry has flourished; the region has successfully attracted several large e-commerce distribution centers and a new shopping mall. Still, the Kasukabe operation remains a critical part of Tokyo's defenses, say officials at Japan's Land Ministry, which runs the site. Five vertical, underground cisterns, almost 250 feet deep, take in stormwater from four rivers north of Tokyo. A series of tunnels connect the cisterns to a vast tank, larger than a soccer field, with ceilings held up by 60-foot pillars that give the space a temple-like feel. From that tank, industrial pumps discharge the floodwater at a controlled pace into the Edo river, a larger river system that flushes the water into Tokyo Bay.
Experts have also questioned the wisdom of erecting more concrete defenses in a country that has dammed most of its major river systems and fortified entire shorelines with breakwaters and concrete blocks. Some of these protections, they say, only encourage development in regions that could still be vulnerable to future flooding. In eastern Saitama, where the Kasukabe facility has done the most to reduce floods, local industry has flourished; the region has successfully attracted several large e-commerce distribution centers and a new shopping mall. Still, the Kasukabe operation remains a critical part of Tokyo's defenses, say officials at Japan's Land Ministry, which runs the site. Five vertical, underground cisterns, almost 250 feet deep, take in stormwater from four rivers north of Tokyo. A series of tunnels connect the cisterns to a vast tank, larger than a soccer field, with ceilings held up by 60-foot pillars that give the space a temple-like feel. From that tank, industrial pumps discharge the floodwater at a controlled pace into the Edo river, a larger river system that flushes the water into Tokyo Bay.
Back in September 2011 two sequential typhoons hit the southern end of Honshu, Japan's main island and the subsequent flooding killed about 90 people. Killer typhoons hit the Japanese islands pretty much every year.
Japan is a dangerous place to live, even more dangerous than California with its earthquakes, mudslides, floods and fires. Planning to control and mitigate such disasters is a necessary part of government hence the uprating of the flood control systems already in place around Tokyo.
Statistics are your mathematical friend. Last we heard, critters other than humans were not digging up long buried hydrocarbons in statistically significant ways and dumping them into the atmosphere to catch those beautiful sun rays.
Try to tell that to countries which check the following boxes:
-high population density
-little develop-able high ground
Examples: Japan, the Netherlands, Bangladesh, various pacific atoll-island nations.
Now filter out the countries that:
-have enough technical expertise to be capable to defend against flooding
-have enough wealth or capability to raise capital to invest in water management projects
-are politically stable enough to effectively plan for long-term flooding defences
Strike the first two, keep the rest.
Be glad you live in a country where non-coastal land is in abundance, for you can ridicule global warming induced rising sea-levels all you like (unless you choose to live in Florida). We know if we don't invest now, and stay investing, we'll be destroyed soon(tm). Water management is a necessary part of keeping our nation... a nation and not a giant flood plane. Having said that, please consider some nations don't have the technology/money to solve these problems they were mostly not responsible for in the first place... Which will probably mean another stream of refugees in a couple of decades. Not that it's of your concern....
Too bad they don't have a plan to deal with sea level rise.
Especially when the big earthquake of 2011 caused a 2 foot drop in the elevation of the Honshu coastline. Sudden events like that are impossible to predict.