G-Cans Project - A Modern Day Wonder.
Most parts of South India have been experiencing heavy rainfall since the last three weeks and the resultant flooding has not just caused disturbances in our day to day lives but there have been reported deaths and damage to property as well. Year after year, we suffer due to improper drainage systems and most of our cities are not equipped to handle even a few hours of shower. If it rains for just an hour, our pothole ridden roads get flooded and the traffic almost stops moving. Power outages are common during rainy season. Life is simply thrown out of gear.
The solution lies in thinking ahead. We seem to lack foresight. When we build airports equipped to handle a certain projected traffic, the same become incapable sooner than we imagine; our roads and highways are not built keeping in mind the increasing vehicular traffic; the quality is dismal and our infrastructure is not made to accommodate the future. We have the best minds, the best talent but foresight and planning is what is eluding us, apart from of course strict adherence to quality.
Many countries are way ahead of us in dealing with not so complex problems with simple but technologically advanced solutions. I feature here the world’s largest underground flood water diversion facility located in Kasukabe, Japan on the outskirts of Tokyo. It was built to deal with and prevent flood water woes of Tokyo during the typhoon season. I know I am being ambitious but just hope that we can learn to handle flooding on roads caused due to normal rains!
The Japanese are masters in planning and execution; the 70s and 80s saw the dominance of Japanese technology, whether it was audio systems, cameras, video games, washing machines, they were there everywhere - leading the pack. Relatively low levels of corruption have also contributed to the Japanese advancements in every field.
The G-Cans project
Japan sits on a typhoon and earthquake prone zone and storms are a common occurrence here due to the conditions in the Pacific Ocean which favour their formation. Major floods in the past have created havoc and destroyed thousands of homes, displaced and even killed many people. The Japanese ingenuity wanted to create something to mitigate the human and economic losses incurred as a result of these massive floods due to super-cyclonic storms. After much deliberation, out came the behemoth G-Cans project (G stands for gesuikanara in Japanese which means drainage canal). To counter flooding caused due to nature’s fury, in 1992, the Japanese Government embarked upon a then “one of a kind” civil engineering project - the largest storm drain on earth called the “G-Cans project” or the “Metropolitan Area Outer Underground Discharge Channel”. It took 17 years to construct this humongous engineering marvel and close to 2 billion dollars to make this dream turn into a reality. It is an underground water infrastructure project which is built to withstand earthquakes of a seismic activity of 7!
How it works
The idea was to divert the flood waters of the neighbouring 5 small rivers into a storage underground which would finally empty it into the nearby Edogawa river. The construction was however not as simple as it sounds. The complexity and precision in the design and execution is an engineering marvel.
This monster of a project is dug 50 m below the river basin and consists of 5 concrete silos, each of which is 65 m high with a diameter of 32 m and they are all connected by a 6.4 kms long tunnel. This size is apparently big enough to house a space shuttle! Five small rivers empty their flood waters into these silos and this is carried in the 6.4 km long tunnel to an Underground Temple , a behemoth subterranean reservoir which has 59 massive pillars (each weighing 500 tons!) and is 177 m long, 25 m high and 80 m wide. From here, 78, 10 MW pumps (which are essentially modified jet engine turbines) pump the water out into the Edogawa (Edo River) at a phenomenal rate of 200 tons per second! This water is then carried by the Edo and emptied into the Tokyo Bay. There is a control room within the tunnel and the storage tank for monitoring the water levels. Water-tightness is maintained at all times within the tunnel.
A tourist destination
The facility is used approximately 7 times in a year but when not in use, it is open for public for free. Many films have been shot here.
This amazing spectacle is worth a visit, though one needs to book at least 4 weeks in advance. This overwhelmingly massive structure is a must-see for anybody visiting Japan.The only drawback though is that the tour is in Japanese. But this problem can be overcome by hiring a Japanese translator.
The Japanese have not only created a spectacular utility but added another modern day wonder!
