:Fujinuma Dam

File:Fujinuma Dam failure.JPG

On 11 March 2011, the dam failed 20 to 25 minutes after the Tōhoku earthquake as the nearly full reservoir overtopped the dam's crest. Locals reported hearing a loud burst before seeing a flood. The flood washed away five houses while damaging others, disabling a bridge and blocked roads with debris. Eight people were missing and four bodies were discovered after searches began at dawn.{{Cite web|title=Dam Breaks in Northeast Japan, Washes Away Homes|url=http://www.arabtimesonline.com/NewsDetails/tabid/96/smid/414/ArticleID/166581/reftab/149/t/Dam-breaks-in-northeast-Japan-washes-away-homes/Default.aspx|work=Arab Times|access-date=14 March 2011|date=12 March 2011}}{{Cite web|last=Azuma|first=Kita|title=Pacific Ocean coast Earthquake|url=http://sankei.jp.msn.com/affairs/news/110312/dst11031205010058-n1.htm|publisher=MSN|access-date=14 March 2011|language=ja|date=12 March 2011|url-status=dead|archive-url=https://web.archive.org/web/20110413124311/http://sankei.jp.msn.com/affairs/news/110312/dst11031205010058-n1.htm|archive-date=13 April 2011}}{{Cite web|script-title=ja:ダム決壊 ５棟流出 福島・須賀川|url=http://jyoho.kahoku.co.jp/member/backnum/news/2011/03/20110313t63033.htm|publisher=Kahoku Shimpo|access-date=14 March 2011|language=ja|date=13 March 2011|url-status=dead|archive-url=https://web.archive.org/web/20110819052423/http://jyoho.kahoku.co.jp/member/backnum/news/2011/03/20110313t63033.htm|archive-date=19 August 2011}} The failure of the earth-fill dam at the Fujinuma reservoir in Fukushima prefecture resulted in eight deaths in a village. [https://www.jstage.jst.go.jp/article/hrl/5/0/5%200%2069/%20pdf https://www.jstage.jst.go.jp/article/hrl/5/0/5 0 69/ pdf]{{Dead link|date=December 2022 |bot=InternetArchiveBot |fix-attempted=yes }}

On 12 March, 252 dams were inspected and seven dams were found to be damaged. Six embankment dams had shallow cracking on their crests and the reservoir at one concrete gravity dam had a slight slope failure. Four dams, including the Fujinuma, were inaccessible and could not be inspected.{{Cite web|title=A quick report on Japanese Dams after the Earthquake|url=http://www.chincold.org.cn/dams/NewsEvents/webinfo/2011/03/1299639147955756.htm|publisher=Chinese National Committee on Large Dams|access-date=15 March 2011|date=13 March 2011}}

A preliminary survey of the dam and facilities conducted in April 2011 noted that the breach occurred at the tallest section of the dam.{{cite web |last1=Kayen |first1=Robert E. |title=LiDAR and Field Investigation Of the March 11, 2011 M9.0 Great Tohoku Offshore Earthquake, and April 7, 2011 M7.4 Aftershock |url=http://www.geerassociation.org/GEER_Post%20EQ%20Reports/Tohoku_Japan_2011/QR6%20LIDAR%20GEER%20Report%2025f%20ver3%20(1-30-12).pdf |work=Geotechnical Extreme Events Reconnaissance (GEER) |publisher=GEER Association |access-date=20 July 2011 |last2=YasuoTanaka |first3=Hajime |last3=Tanaka |first4=Takahiro |last4=Sugano |first5=Ivan A. |last5=Estevez |first6=Sean S. |last6=Cullenward |first7=Winnie |last7=Yeh |first8=Davis |last8=Thomas |date=20 July 2011 |archive-url=https://web.archive.org/web/20130517071721/http://www.geerassociation.org/GEER_Post%20EQ%20Reports/Tohoku_Japan_2011/QR6%20LIDAR%20GEER%20Report%2025f%20ver3%20(1-30-12).pdf |archive-date=17 May 2013 |url-status=dead }} Within the dam's fill, there were layers of organic residual soil that in one area contained a tree stump. The residual soil was used as foundation and in layers as well – above alluvium. This suggests that the foundation for the dam was not prepared properly, according to the study. In addition, the reservoir's auxiliary dam suffered a severe slope failure on its upstream face while areas around the rim of the reservoir had mild slope failures or distress. It could not be confirmed whether the earthquake or a quick draining of the reservoir was the cause of this.

The dam was a {{Convert|18.5|m|ft|0|abbr=on}} tall and {{Convert|133|m|ft|0|abbr=on}} long embankment-type with a structural volume of {{Convert|99000|m3|ft3|0|abbr=on}} and crest width of {{Convert|6|m|ft|0|abbr=on}}. About {{Convert|300|m|ft|0|abbr=on}} to the south, there is an auxiliary dam with a height of about {{Convert|6|m|ft|0|abbr=on}} and length of approximately {{Convert|60|m|ft|0|abbr=on}}. The auxiliary dam helped the reservoir maintain it designed levels given the topography wouldn't allow the single main dam to do so. The dam sat at the head of a {{Convert|8.8|km2|sqmi|0|abbr=on}} drainage area and its reservoir had a capacity of {{Convert|1504000|m3|acre.ft|0|abbr=on}}. The reservoir had a surface area of {{Convert|20|ha|acre|0|abbr=on}}. The dam was built by Shoji Kensetsu and operated by Ebana River Coastal Reclamation District.{{Cite web|title=Fujinuma Dam - Dam Handbook|url=http://damnet.or.jp/cgi-bin/binranA/All.cgi?db4=0483|publisher=Dam Association of Japan|access-date=14 March 2011|language=ja}}

After the dam’s failure, there were conflicts between the governmental reviews and the citizens’ understanding of why the dam experienced such failure. Japanese national and Fukushima prefectural governments inspected and considered that the earthquake’s impact was significant damage triggered and stated it a natural disaster. Oppositely, the failure mentioned above, such as lack of workforce, knowledge, and proper materials in the construction process,{{Cite web |last=ダムマニア: DamMania |date=June 23, 2015 |title=藤沼ダム |url=https://dammania.net/fukusima/fujinuma.html |url-status=live}} the citizens doubt that this failure is a human-made disaster and the consequences of the construction failures; especially Sukagawa city is far away from the ocean to experience Tsunami, so, they couldn't consider it as a natural disaster. {{Cite web |last=産経ニュース |date=June 8, 2011 |title=藤沼ダム決壊の続報: 　ー震災でダム決壊「人災」 見舞いの知事に怒り 福島・須賀川ー |url=https://yamba-net.org/38709/ |url-status=live}}

These opposing opinions can also be seen in the discussion and conflict about disaster public assistance by the governing sectors. In Japan, when there is a natural disaster, there is a regulation of maximum financial support of 3 million yen,{{Cite web |last=福島県: Fukushima Prefecture |title=福島県被災者住宅再建支援事業について |url=https://www.pref.fukushima.lg.jp/sec/16025b/jyutakusaiken.html |url-status=live}}{{Cite web |last=内閣府: Government of Japan |title=内閣府防災情報ページ：公的支援制度について |url=https://www.bousai.go.jp/kyoiku/hokenkyousai/sienseido.html |url-status=live}} however, in this case, the citizens’ understanding of this dam failure was a human-made disaster, so the disaster public assistance financial support did not meet citizens’ needs and created this disaster to more complicated situation to battle against the governmental perspective on assistance and approach for dam failure, especially on recovery discussion. {{Cite web |last=産経新聞 |date=June 8, 2011 |title=藤沼ダム決壊の続報:　－人災？天災？ 藤沼ダムの決壊…怒り、揺れる住民― |url=https://yamba-net.org/38709/ |url-status=live}}

Reconstruction of the dam started in October 2013,[http://www.jsidre.or.jp/wordpress/wp-content/uploads/2016/03/r_14_83-10.pdf 藤沼ダムの決壊原因と復旧方針について] - 渡辺健、渡邊浩樹、農業農村工学会誌[http://kensetsunewspickup.blogspot.jp/2013/11/blog-post_27.html 【復興版】震災で堤体決壊の藤沼ダム復旧が着工] - 建設通信新聞公式記事ブログ、日刊建設通信新聞社、2013年11月27日 and has been completed in April 2017.{{Cite news |title=藤沼ダム農業用水供給再開 |url=http://abukumajiho.net/20170425_6218 |work=あぶくま時報 |publisher=阿武隈時報社 |date=2017-04-25 |access-date=2017-06-11 |archive-url=https://web.archive.org/web/20171028150341/http://abukumajiho.net/20170425_6218 |archive-date=28 October 2017 |url-status=dead }}

Although the recovery of this dam was completed in 2017, there were some unheard voices of citizens living near the once-failed dam. Three main arguments were: 1) recovery and water are needed for their agricultural business, 2) potential risk of flood to reconstruct at the same location, and 3) no dam is needed. {{Cite web |last=産経新聞 |date=June 10, 2011 |title=藤沼ダム決壊の続報: 　－不安募る梅雨 震災で貯水池・農業用ダム８６カ所損傷 補修予算わずか１億― |url=https://yamba-net.org/38709/ |url-status=live}}

• Dam failure

{{reflist}}

{{commons category}}

{{2011 Tōhoku earthquake and tsunami}}

{{Dams in Fukushima Prefecture}}

Category:Dams in Fukushima Prefecture

Category:Dam failures in Asia

Category:2011 Tōhoku earthquake and tsunami

Category:Dams completed in 1949

Category:Man-made disasters in Japan

Category:Buildings and structures destroyed by the 2011 Tōhoku earthquake and tsunami