On 8th May 2017, several forest fires had widely occurred in three prefectures in Tohoku region due to common climate condition of dried ground surface and strong wind. In Kamaishi case in Iwate prefecture, its burnt area was larger than the total burnt area recorded in 2016 for the whole Japan. It was results of strong wind and low accessibility for vehicles. While, the feature of Kurihara case in Miyagi prefecture was fire-flying expansion. Ground expansion was prevented by surrounding paddy fields, but strong wind enabled fires to fly around 500m in maximum. The aim of this article is to clarify the actual process of expansion and extinction activity based on field investigation and interviewing, which will contribute to effective way of fire extinction in future.

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Heavy rain caused by the linear rainfall zone settling on the same place for a long time attacked Asakura, Fukuoka Prefecture and Hita, Oita Prefecture in July 5, 2017. The daily precipitation recorded 545.5 mm in the Asakura meteorological station. Many disasters such as flood, slope collapse and mud flood occurred, and that damage resulted in 37 deadperson, 4 missing person and 1406 buildings destroyed. We investigated and reported the damage state by this disaster in five river basins: the Kagetsu river, the Oohi river, the Akatani river, the Shirakitani river and the Sada river.

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A heavy rainstorm by Typhoon No.18 “Tyhoon Talim” attacked Central Southern part of Oita Prefecture, Kyushu, Japan on September 17, 2017. At the Tsukumi observatory daily precipitation (September 17) and maximum 1 hour precipitation (September 17, 15:38) recorded 427.0 mm and 129.5 mm, respectively. Furthermore, in Sobo mountains along the prefectural border between Oita and Miyazaki, the daily precipitation exceeded 500mm. The flood disaster occurred in Usuki, Tsukumi and Saeki cities by a heavy rain. The flood damage resulted in 522 buildings partially destroyed and 2,800 buildings flooded in Oita Prefectures.

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The present study examined the accounts of principals of 31 elementary and junior high schools in the Japanese prefectures of Iwate, Miyagi, and Fukushima who took part in emergency response efforts in schools during the Great East Japan Earthquake. The content of their actions was categorized and organized according to the four stages of an emergency decision-making model known as at the OODA Loop(consisting of “Observation”, “Orientation”, “Decision”, and “Action”). From the results, the following observations were identified as factors that impede smooth progression through the stages of the OODA Loop(i.e., necessitate more time for decision-making). First, at the Observation stage, collection of information became difficult due to power outages, and principals and teaching staff did not take the initiative to gather information on their own. Second, at the Orientation stage, it was impossible to apprehend the “actual situation”, as well as its ramifications, due to failure to gather information immediately after the disaster, and there was a lack of “planning” or preparations based on prior assumptions due to the incompleteness of disaster-response manuals and training among other reasons.Third, at the Decision stage, options for potential actions were not immediately clear, available options for actions were limited, and actions once taken were not or could not be changed, or the unconscious decision to “do nothing” continuously prevailed. Fourth, at the Action stage, a specific action either became the entire focus of action, or else actions, once taken, were continuously second-guessed and changed.

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This study examined the flooding disaster resulting from the heavy rainfall that was associated with Typhoon No. 10 in northern Iwate Prefecture in August 2016. Meteorological data for Typhoon No. 10, which landed in the Tohoku district on the Pacific Ocean-side of Japan, was obtained from the Japan Meteorological Agency. The typhoon lasted for 11 days and caused extensive damage in the Tohoku district, particularly in Iwaizumi town and Kuji city, which were severely damaged by flooding of the Omoto and Kuji rivers. We conducted field investigations from November 18 to 21, 2016 and collected data from disaster section in Kuji city hall and Iwate Prefecture. In the residential and commercial districts of Kuji city, an area of approximately 0.63 km2 was inundated after an embankment overflowed, causing one fatality and flooding of 2,258 houses. Flooding was increased by the presence of numerous trees in the floodwaters; the trees collected at bridges and interfered with the flow of the Kuji River. By partially blocking the river, water levels rose and the embankment was ruptured causing flooding. Flooding in the Kuji River was severe because a river master plan had not been developed for the river. In the Omoto and Shizu subcatchment, the number of fatalities and missing people in six districts of Iwaizumi town was 19 and 2, respectively. In addition, 419 houses and businesses were flooded and 1.23 km2 of farmland was inundated. As in the Kuji River, trees that were transported down the river from areas upstream collected at bridges and impeded the flow of water, causing water levels to rise and river embankments, which had not been sufficiently maintained, to overflow.

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We developed a victim data base (“2004-2014”) for heavy rainfall disaster events in Japan from 2004 to 2014, and 712 victims were classified. The purpose of this study is to analyze the characteristics of victims caused by typhoon No.1610 disaster in northern Japan on August, 2016 (“T1610”) in comparison with “2004-2014”. Through this typhoon, 23 people were killed in Iwate Prefecture and Hokkaido, and 4 people were missing. Characteristics of victims by “T1610” were as follows: 1) 74% of the victims were death by flood disaster. 2) 78% of victims were elderly people with the ages of 65 years or older. 3) 30% of the victims died after taking evacuation action. The ratio of 1) is higher than “2004-2014”. T1610 was a so-called “mountain river flood disaster”. This type of flood tends to cause great damage. The ratio of 2) is higher than “2004-2014” too. In particular, nine elderly people died in a nursing home. The difficulty of evacuation of the elderly people was indicated. The ratio of 3) is higher than “2004-2014”. It is necessary to further think about the timing and method of evacuation. On the other hand, in the Acca area of Iwaizumi-town, 11 houses were destroyed but only 1 person died. It is likely that many residents were saved by active evacuation in this area.

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Driftwood in rivers seriously increases the destructive power of flood flow. Large driftwood accumulates at a bridge and blocks the river, which leads to a decreased discharge capacity and increased water levels. In Uji city in August 2012, the detour flood-flow occurred around the bridge and the house along Shizugawa River was washed away. However, there is almost no detailed information about flood discharge of a detour flow around a bridge and flood damage area in a blocked river. In this study, three kinds of flume experiments were performed. First, we conducted the driftwood accumulation tests at the model bridge to evaluate the porosity of driftwood blocking. Then, we measured the flood flow velocity in the blocked river by PIV to estimate the flood discharge on floodplains. Finally, the drag force exerted on the model house on floodplain was measured using Force gauge to examine the flood damage of the nearby area.

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