Image: Tsunami inundation
AP / Kyodo file
The water from a tsunami wave hits residences in Natori after the Japanese earthquake of March 11, 2011.
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updated 4/1/2012 10:19:13 PM ET 2012-04-02T02:19:13

Much of Japan's Pacific coast could be inundated by a tsunami more than 112 feet (34 meters) high if a powerful earthquake hits offshore, according to revised estimates by a government panel.

The panel of experts says any tsunami unleashed by a magnitude-9.0 earthquake in the Nankai trough, which runs east of Japan's main island of Honshu to the southern island of Kyushu, could top 34 meters at its highest.

An earlier forecast in 2003 put the potential maximum height of such a tsunami at less than 66 feet (20 meters).

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Last March's magnitude-9.0 earthquake spawned a 45-foot (14-meter) wave that devastated most of Japan's northeastern coast and triggered meltdowns at a nuclear power plant.

The revised tsunami projections, contained in a report released Saturday and posted on a government website, are based on new research following last March's magnitude-9.0 earthquake and tsunami, which devastated a long stretch of Japan's northeastern coast and killed about 19,000 people.

Sweeping reviews
Last year's catastrophe and the ensuing crisis at the Fukushima Dai-ichi nuclear power plant, prompted sweeping reviews of Japan's disaster preparedness and criticism over apparent failures to take into account potential risks.

The tsunami knocked out power at the 40-year-old coastal nuclear plant, leading to the worst nuclear disaster since Chernobyl in 1986. Tens of thousands of residents have had to leave the area, and it's unclear whether some will ever be able to move back.

The Fukushima plant was designed to withstand a 20-foot (6-meter) tsunami, less than half the height of the surge that hit it on March 11, 2011.

The latest forecast shows a tsunami of up to 69 feet (21 meters) could strike near the Hamaoka nuclear plant. Its operator, Chubu Electric Power Co., is building a 59-foot-high (18-meter-high) sea wall to counter tsunamis. The wall is due to be completed next year.

The plant was shut down in 2011, due to estimates that it has a 90 percent chance of being hit by a magnitude 8.0 or higher quake within 30 years.

More unsettling news
Another government report shows that a strong earthquake hitting the Tokyo Bay region could shake the Tokyo-Yokohama metropolitan area — home to more than 33 million people — at the maximum seismic intensity of 7 on the Japanese scale.

The report, issued Friday by the Ministry of Education, came in the form of mapping that shows that much of the Tokyo region would likely experience severe shaking from a magnitude-7.3 earthquake inside Tokyo Bay.

The study prompted calls for Tokyo residents to be better prepared for such disasters. Although they live with the constant threat of a major earthquake that experts have long said is overdue for the region, not all living in the region keep recommended water and other supplies on hand.

A report in the newspaper Asahi Shimbun listed troubles that might be expected from a major quake, such as electricity outages that could persist for more than a week and water supply disruptions that could last for nearly a month, based on government estimates.

The revised tsunami forecast for a possible Nankai earthquake says Tokyo could expect waves up to 7.6 feet (2.3 meters) high. But at the coastal town of Kuroshio, on the island of Shikoku, the tsunami could top 112 feet (34 meters), it shows.

The computer modeling for the revised forecasts assumes a high tide for the highest estimates.

© 2013 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Photos: Triple tragedy for Japan

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  1. Office workers in Tokyo look at smoke rising over the skyline after the magnitude 9.0 earthquake off Japan's northeast coast on March 11, 2011. (Xinhua via Getty Images) Back to slideshow navigation
  2. Waves pour over a seawall and roar into a seaside village near the mouth of Hei River on March 11 as the tsunami generated by the massive earthquake hits shore. (Mainichi Newspaper via EPA) Back to slideshow navigation
  3. Hotel employees squat around a pillar at the hotel's entrance in Tokyo after the powerful earthquake on March 11. (Itsuo Inouye / AP) Back to slideshow navigation
  4. A tsunami wave sweeps away homes in its path in Natori, Miyagi prefecture, on March 11. (Kyodo News via AP) Back to slideshow navigation
  5. One house bursts into flames after the tsunami swept it and many of its neighbors off their foundations in Natori on March 11. (Kyodo News via Reuters) Back to slideshow navigation
  6. Shaken evacuees gather in Shinjuku Central Park in Tokyo on March 11. (Kyodo News via Reuters) Back to slideshow navigation
  7. An aerial photo shows Sendai Airport being inundated by a tsunami on March 11. Later reports said the first wave hit 26 minutes after the quake struck at 2:46 p.m. local time. (Kyodo News via Reuters) Back to slideshow navigation
  8. A swirling pattern is evident in this aerial photo of the tsunami as it hit a port in Oarai, Ibaraki prefecture on March 11. (Kyodo News via AP) Back to slideshow navigation
  9. Toya Chiba, a reporter for local newspaper Iwate Tokai Shimbun, is swept away while taking pictures at the mouth of the Owatari River during the tsunami at Kamaishi port, Iwate prefecture. Chiba managed to survive in the rush of water by grabbing a dangling rope and climbing onto a coal heap around 30 feet high after being swept away for about 100 feet, Kyodo News reports. (Kamaishi Port Office / Kyodo via Reuters) Back to slideshow navigation
  10. Natural gas containers burn in Chiba Prefecture near Tokyo, on March 11. The massive earthquake triggered many fires, posing additional problems for first responders. (Kyodo News via Reuters) Back to slideshow navigation
  11. Containers for cargo are strewn about like giant Legos in Sendai, Miyagi prefecture, on March 12. (Itsuo Inouye / AP) Back to slideshow navigation
  12. People use a floating container to ferry survivors to higher ground in Kesennuma City, Miyagi prefecture, on March 12. (Kyodo News via Reuters) Back to slideshow navigation
  13. Cars swept into a jumble by the tsunami are seen in Hitachi City, Ibaraki prefecture, on March 12. (Yomiuri via Reuters) Back to slideshow navigation
  14. A line of residents seeking water snakes across the playground of a school in Sendai, Miyagi prefecture, on March 13, two days after the earthquake. (Kyodo News via AP) Back to slideshow navigation
  15. Japanese firefighters rescue tsunami survivors in Natori, Miyagi prefecture, on March 13. (EPA) Back to slideshow navigation
  16. A Japanese home drifts in the Pacific Ocean off the coast of Sendai in this photograph taken on March 13. (Dylan McCord / U.S. Navy via Reuters) Back to slideshow navigation
  17. A woman cries while sitting on a road in the devastated city of Natori, Miyagi prefecture, on March 13. (Asahi Shimbun / Reuters) Back to slideshow navigation
  18. An "SOS" signal scrawled on the sports field of a high school beckons potential rescuers on March 13 in the town of Minami Sanriku, Miyagi prefecture. (Kyodo News via Reuters) Back to slideshow navigation
  19. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

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    The body of a victim of the twin disaster lays on the stairs of a destroyed house in Sendai, Miyagi prefecture, on March 13. (David Guttenfelder / AP) Back to slideshow navigation
  20. Sixty-year-old Hiromitsu Shinkawa waves to members of Japan Maritime Self-Defence Force preparing to rescue him about 9 miles off Fukushima prefecture on March 13. Shinkawa survived by clinging to a piece of roof after the tsunami hit his hometown of Minamisoma. (Japanese Defense Forces via AFP - Getty Images) Back to slideshow navigation
  21. People walk along a flooded street in Ishimaki City, Miyagi prefecture on March 13. (Kyodo News via Reuters) Back to slideshow navigation
  22. An explosion at the Fukushima Dai-ichi nuclear power plant sends a plume of smoke skyward on March 14. The blast was believed to have been caused by a buildup of hydrogen inside the reactor building, caused by the partial meltdown of nuclear fuel inside. The plant was crippled after the earthquake cut power to the station and tsunami waves knocked out backup generators. (NTV / FCT) Back to slideshow navigation
  23. A 1-year-old boy is re-checked for radiation exposure after being decontaminated in Nihonmatsu, Fukushiima prefecture, on March 14. (Toru Nakata / Asahi Shimbun via AP) Back to slideshow navigation
  24. Officers examine a Mitsubishi F-2 fighter jet of the Japanese Air Self-Defense Force on March 14. The warplane was swept by the tsunami into a building at Matsushima base in Higashimatsushima, Iwate prefecture. (Kyodo News via Reuters) Back to slideshow navigation
  25. Japanese rescue team members carry the body of a man out of the village of Saito on March 14. (David Guttenfelder / AP) Back to slideshow navigation
  26. A woman survivor is reunited with her relatives at a shelter in Rikuzentakata in Iwate prefecture, on March 15. (Lee Jae-Won / Reuters) Back to slideshow navigation
  27. A bicyclist wheels across a hellish landscape in what was the city of Minami Sanriku, Miyagi prefecture, on March 15. (David Guttenfelder / AP) Back to slideshow navigation
  28. Tsunami survivors cook on an open fire in front of their damaged house in Ishinomaki, Miyagi Prefecture, on March 15. (Kyodo News via AP) Back to slideshow navigation
  29. Vehicle headlamps illuminate a devastated section of Yamada town, Iwate prefecture, on March 16. (Jiji Press via AFP - Getty Images) Back to slideshow navigation
  30. Evacuees carry bowls of pork soup from a soup kitchen to a makeshift shelter in Minami Sanriku, Miyagi prefecture, on March 16. (Tsuyoshi Matsumoto / The Yomiuri Shimbun via AP) Back to slideshow navigation
  31. Refugees, including 53 people who were rescued from a retirement home during the tsunami, take shelter inside a school gym in the leveled city of Kesennuma, Miyagi prefecture, on March 17. (David Guttenfelder / AP) Back to slideshow navigation
  32. Members of Japan Self-Defense Force pray over the body of a tsunami victim in Onagawa, Miyagi prefecture, on March 20. (Shuji Kajiyama / AP) Back to slideshow navigation
  33. Tomoko Yagi looks at two firetrucks that were tossed around like toys in the tsunami in Kamaishi, Iwate prefecture, on March 20. (Lee Jae-Won / Reuters) Back to slideshow navigation
  34. Survivors relay boxes of relief supplies arriving at their evacuation center in Ishinomaki, Miyagi prefecture, on March 21. (Kunihiko Miura / The Yomiuri Shimbun via AP) Back to slideshow navigation
  35. A boat juts out from the top of a building in Otsuchi, Iwate prefecture, on March 22. (Hiroto Nomoto / The Yomiuri Shimbun via AP) Back to slideshow navigation
  36. Manami Kon, 4, uses the Japanese "hiragana" characters she just learned to write a letter to her missing mother in the devastated city of Miyako, Iwate prefecture, on March 22 . "Dear Mommy. I hope you're alive. Are you OK?" read the letter, which took about an hour to write. Also missing were the little girl's father and sister. (Norikazu Tateishi / The Yomiuri Shimbun via AP) Back to slideshow navigation
  37. Tokyo Electric Power Co. workers collect data in the control room for the Unit 1 and 2 reactors at the crippled Fukushima Dai-ichi nuclear power plant on March 23. (Nuclear and Industrial Safety Agency via AP) Back to slideshow navigation
  38. An aerial photo taken by an unmanned drone shows the damaged units of the Fukushima Dai-ichi nuclear plant on March 24. (Air Photo Service via EPA) Back to slideshow navigation
  39. Two residents exchange words as they are reunited two weeks after the earthquake and tsunami in a makeshift public bath set up outside a shelter in Yamamoto, Miyagi prefecture, on March 25. (Shuji Kajiyama / AP) Back to slideshow navigation
  40. A Japanese funeral parlor worker shovels dirt onto the coffins of victims of the earthquake and tsunami at a mass funeral in Yamamoto, Miyagi prefecture, on March 26. (David Guttenfelder / AP) Back to slideshow navigation
  41. A lone pine tree stands in a devastated area iof Rikuzentakaka, Iwate prefecture, on March 27. It was the only one among tens of thousands of other pine trees forming "Takata Matsubara," or Takata seaside pine forest, standing after the March 11 tsunami washed away all the others, local media said. (Kyodo News via AP) Back to slideshow navigation
  42. A woman whose house was washed away loses control of her emotions on March 29 as she talks about the disaster that befell her hometown of Kesennuma, Miyagi prefecture. (Kuni Takahashi) Back to slideshow navigation
  43. Japanese Emperor Akihito and Empress Michiko, left, talk with evacuees at Tokyo Budoh-kan evacuation center on March 30. (Issei Kato / Pool via AFP - Getty Images) Back to slideshow navigation
  44. Officials of the Tokyo Electric Power Co., (TEPCO), including Chairman Tsunehisa Katsumata, center, Vice President Takashi Fujimoto, second from left, bow before a news conference at the company's head office in Tokyo on March 30. (Itsuo Inouye / AP) Back to slideshow navigation
  45. A man rides a bicycle in between the ships that were washed ashore by the March 11 tsunami, on March 30, in Kesennuma, Miyagi prefecture. (Eugene Hoshiko / AP) Back to slideshow navigation
  46. An elderly woman waves to her grandchildren in Minamisanriku, Miyagi prefecture, on April 3, as authorities began a mass evacuation of approximately 1,100 homeless survivors to shelters elsewhere. (Jiji Press via AFP - Getty Images) Back to slideshow navigation
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    This image contains graphic content that some viewers may find disturbing.

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  2. Editor's note:
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  3. Editor's note:
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  4. Editor's note:
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