Flood control: Destroying neighborhoods to save them

October 24th, 2010 by Philip Brasor & Masako Tsubuku

Money in the bank: Super teibo explanation along Arakawa River

Money in the bank: Super teibo explanation in Oshima Komatsugawa Park, Edogawa Ward, Tokyo

Next week, the most entertaining show in town, the deliberations of the Government Revitalization Unit, which holds hearings on government programs with the aim of cutting budegetary waste, will start again. According to various news reports, one of the main targets of the council this time will be the long-term public works project to improve flood control effectiveness in Tokyo and Osaka. Though Japanese rivers that pass through urban and suburban areas usually have extensive levee systems, some of which are centuries old, these embankments are thought to be no guarantee against the inundation of bordering communities in the event of a major storm. In 1986, a levee in Ibaraki Prefecture collapsed causing damage to surrounding neighborhoods, thus prompting the Liberal Democratic Party government at the time to initiate an ambitious public works project to shore up all the levees in the Tokyo and Osaka metropolitan areas, where many residences are actually situated below sea level. In the Kanto region, this project is being carried out for the Tone, Edo, Arakawa and Tama Rivers; while in Kansai construction is taking place on the Yodo and Yamate Rivers. Altogether,  872.4 km of waterways are targeted.

The method of reinforcement is to build “super teibo.” Teibo is the Japanese word for “levee” or “embankment.” Existing levees are essentially elevated banks that separate residences from the river. A super teibo would extend the elevation into the residential area, effectively raising the level of the area higher than the level of the river. In the event of a flood that rose above the level of the levee, not only would the levee hold, but the amount of water inundating inhabited areas would be greatly reduced.

You don’t have to be a civil engineer, however, to realize the vast amount of work this plan calls for. The construction ministry, working with local governments, must persuade local residents to move out of the affected areas for up to four years while the super teibo is built. Homes are removed and then new ones are rebuilt in their places (only at a slightly higher altitude), so the costs are also significant.

Given that Japan has a very weak concept of eminent domain, the biggest obstacle to the super teibo project is getting people to move. Consequently, construction has moved at a snail’s pace. A report last week on TBS used the Yodo River as an example. In the 23 years since the super teibo project started, only 4.9 kilometers — or 5.4 percent – of the river’s 89.2 km have been reinforced. At that rate, it will take 400 years to finish the job. Moreover, the government has spent ¥137 billion on these 4.9 km, which means the cost of reinforcing the whole river will come to at least ¥2.4 trillion. Right now, only 5.8 percent of work on all six rivers has been completed.

The total cost for this centuries-long construction is now projected to be ¥24 trillion, which is why the GRU is looking into it. The main problem is that the super teibo project is classified as a tokubetsu kaikei (special accounts budget) enterprise. Tokubetsu kaikei projects are not subject to periodic audits. Once the project is approved, budgets are guaranteed, and, obviously, the possibility of over-spending is higher.

According to TBS, the GRU’s main ammunition is the necessity of the super teibo system itself. Climate experts say the amount of rainfall necessary to cause the kind of flooding that the system is built to withstand occurs in Japan about once every 32,000 years. “It’s like preparing weapons for a possible attack by extraterrestrials,” one Democratic Party of Japan lawmaker said about the super teibo project. TBS notes that the project’s approval coincided with pressure from America in the 1980s for Japan to increase domestic consumption. This pressure resulted in all sorts of major public works projects, many of which have since been criticized as white elephants.

But even if the new levees do help protect neighborhoods from flood disasters, will there be any neighborhoods to protect after they are built? In 2000, the government finally convinced 72 households along one stretch of the Edo River to move out so that they could build a super teibo. After construction was completed in 2004, only 38 returned to the area. The community, which had been there for generations, was effectively destroyed. Many of the people who took the government’s removal money simply used it to buy property somewhere else and settled there. Moreover, the protracted negotiations the government carried out to persuade the residents to move split the neighborhood between those who approved the evacuation and those who didn’t, thus causing inter-community enmities that were impossible to repair. Sometimes, the negative effects of a public works projects go beyond matters of money.

Tags: , ,

One Response

  1. Great post. Thanks for your work.


Recent posts