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Fifth US- Conference on Flood Control and Water Resources Management January 2009

Flood damage mitigation efforts in Japan

Toshiyuki Adachi Director, River Planning Division, River Bureau Ministry of Land, Infrastructure, Transport and Tourism (MLIT)

Ministry of Land, Infrastructure, Transport and Tourism

Ministry of Land, Infrastructure, Transport and Tourism Ministry of Land, Infrastructure, Natural conditions of Japan Transport and Tourism

Long and slim archipelago about 2,000 km long in the north- ①Topography south direction Elevation legend (m or higher)

②Four main The four main islands separated by straits, and many smaller islands islands

③Backbone Mountain ranges running longitudinally at the center of Japan mountain ranges roughly divides the country into two halves.

The Median Tectonic Line and the Itoigawa- ④Tectonic lines Tectonic Line run north to south across the island.

Small plains along the coastlines (about 14% of the total land ⑤Plains area)

⑥Soft ground Most of the large cities in Japan are located on weak ground. Itoigawa-Shizuoka糸魚川－静岡構造線 Tectonic Line

About 10% of all earthquakes in the world occur in or around ⑦Earthquake Japan. ne nic Li線 ecto造 an央 T 構 Me中di Rainy weather (mean annual precipitation: 1,714 mm, which is ⑧Heavy rain about two times as much as that in the European countries); steep rivers

About 60% of the country is located in snowy cold regions ⑨Snow (annual cumulative snowfall: more than 4 m in many cities).

※Snowy region: The average of maximum snow depths in February is 50 cm or more. Cold region: The average of mean temperatures in January is 0ºC or lower. 1 Ministry of Land, Infrastructure, Transport and Tourism

１．Basic system of measures for flood damage mitigation in Japan

２．Preparedness for major floods

・Past major floods and state-level efforts ・Role of the Ministry of Land, Infrastructure, Transport and Tourism

2 Ministry of Land, Infrastructure, MLIT's disaster prevention efforts Transport and Tourism

Crisis response Disaster prevention Occurrence ・Patrolling rivers ・Reporting damage status ・River improvement of flood ・Observing and predicting precipitation and ・ Dam construction water level ・ Provision of river information system ・Delivering flood warnings, etc. ・Improvement of forecasting and warning systems ・Maintenance of rivers ・Construction of disaster prevention stations, etc.

Emergency measures and restoration/recovery ・Implementing emergency restoration measures ・Implementing post-disaster recovery measures ・Restoration/recovery of affected areas 3 Ministry of Land, Infrastructure, Disaster response laws related to MLIT Transport and Tourism Disaster Measures Basic Act

◆Establishes systems necessary for disaster prevention. ◆Clarifies where the responsibility for disaster prevention lies. ◆Stipulates basic requirements for disaster prevention planning and necessary basic disaster prevention measures such as emergency measures.

◆Aims to make comprehensive ◆Aims to prepare people for floods management of rivers so as to and storm surges, protect people prevent river-related disasters such from them and mitigate damage as floods and storm surges. due to floods and storm surges.

River Act Flood Protection Act 4 Ministry of Land, Infrastructure, Disaster Measures Basic Act November 15, 1961, Law No. 223 Transport and Tourism

This law aims to protect life, health and property of the people of Japan and thereby contribute to the maintenance of public order and the achievement of public welfare.

1. Definition of disasters 1.1. Definition Definition of of disasters disasters ○Natural disaster: disaster caused by anomalous natural phenomenon such as an earthquake or heavy rain ○Natural disaster: disaster caused by anomalous natural phenomenon such as an earthquake or heavy rain ○Accident disaster: disaster caused by a major accident such as a large-scale fire or explosion, a large-scale spill of a radioactive substance or a ship wreck involving○Accident many disaster: people disaster caused by a major accident such as a large-scale fire or explosion, a large-scale spill of a radioactive substance or a ship wreck involving many people

2. Clarification of where the responsibility for disaster prevention lies 2.2. Clarification Clarification of of where where the the responsibility responsibility for for disaster disaster preven preventiontion lies lies ○Responsibilities of the state, prefectural and municipal governments and designated public organizations: Formulation and implementation of and cooperation concerning○Responsibilities plans related of the to state, disaster prefectural prevention, and etc.municipal governments and designated public organizations: Formulation and implementation of and cooperation concerning plans related to disaster prevention, etc. ○Responsibilities of the public: Preparedness for disasters, participation in voluntary disaster prevention activities, etc. ○Responsibilities of the public: Preparedness for disasters, participation in voluntary disaster prevention activities, etc.

3. Organization related to disaster prevention: Establishment and 4. Disaster prevention planning: Establishment and implementation of 3. Organization related to disaster prevention: Establishment and 4. Disaster prevention planning: Establishment and implementation of implementation of comprehensive disaster prevention administration systematic disaster prevention administration implementation of comprehensive disaster prevention administration systematic disaster prevention administration ○State level: Central Disaster Prevention Council, headquarters for ○ Central Disaster Prevention Council: Basic disaster prevention plan emergency○State level: disaster Central control Disaster Prevention Council, headquarters for ○ Central Disaster Prevention Council: Basic disaster prevention plan emergency disaster control ○ Designated administrative organizations and designated public ○Prefectural and municipal levels: local disaster prevention councils, disaster organizations:○ Designated operation administrative plans fororganizations disaster prevention and designated public response○Prefectural headquarters and municipal levels: local disaster prevention councils, disaster organizations: operation plans for disaster prevention response headquarters ○ Prefectural and municipal levels: regional plans for disaster prevention ○ Prefectural and municipal levels: regional plans for disaster prevention

5. Implementation of disaster prevention measures 5.5. Implementation Implementation of of disaster disaster prevention prevention measures measures ○The role and authority of each entity at the stages of disaster prevention, emergency response and post-disaster recovery are stipulated. ○The role and authority of each entity at the stages of disaster prevention, emergency response and post-disaster recovery are stipulated. Mayors are authorized to give evacuation directions, designate warning areas, order emergency expropriation, etc. (Municipal governments are primarily responsible for disaster prevention measures.)

6. Fiscal and monetary measures 6.6. Fiscal Fiscal and and monetary monetary measures measures ○Principle: "Implementers Pay" principle ○Principle: "Implementers Pay" principle ○Exceptions: Special financial assistance from the state government to local governments in the event of an extreme disaster, etc. →Act Concerning Special Financial Assistance○Exceptions: Etc. in Case Special of Severe financial Disaster assistance from the state government to local governments in the event of an extreme disaster, etc. →Act Concerning Special Financial Assistance Etc. in Case of Severe Disaster

7. Disaster emergencies 7.7. Disaster Disaster emergencies emergencies ○Declaration of a disaster emergency ⇒Establishment of emergency response headquarters ○Declaration of a disaster emergency ⇒Establishment of emergency response headquarters ○Emergency measures (restriction on distribution of daily necessities, grace for payment, the adoption of emergency government ordinances regarding the acceptance○Emergency of assistance measures from(restriction other countries)on distribution of daily necessities, grace for payment, the adoption of emergency government ordinances regarding the acceptance of assistance from other countries) 5 Ministry of Land, Infrastructure, River Act (disaster-related provisions)July 10, 1964, Law No. 167 Transport and Tourism

Purpose The purpose of this law is to manage rivers in a comprehensive manner in order to prevent disasters resulting from floods, storm surges, etc.

River administrators Class A rivers: Minister of Land, Infrastructure, Transport and Tourism * The management of designated river sections is relegated from the Minister of Land, Infrastructure, Transport and Tourism to prefectural governors. Class B rivers: Prefectural governors River administrators manage rivers in a comprehensive manner. Major disaster response measures Emergency measures in the event of flood ・The river administrator may use or expropriate necessary land, earth materials, bamboos, wood or other materials and use vehicles or other transportation equipment or devices, or dispose of structures or other obstacles or have people who live near or are present at the flood hazard site perform the flood protection activities.

Role of the state government in times of emergency Directions of the Minister of Land, Infrastructure, Transport and Tourism ・In the event that a disaster has occurred or is likely to occur because of a flood, storm surge, etc. and it is deemed necessary in order to prevent or mitigate such disaster, the Minister of Land, Infrastructure, Transport and Tourism may direct the prefectural governor who performs part of the management of a in a designated section or the management of a Class B river to take necessary measures. 6 Ministry of Land, Infrastructure, Flood Protection Act (disaster-related provisions) June 4, 1949, Law No. 193 Transport and Tourism

Purpose The purpose of this law is to watch for and guard against water-related disasters caused by floods or storm surges and mitigate damage in order to maintain public safety. Flood protection manager The head of the municipal government or flood defence association that is a flood protection management organization Major damage mitigation measures ・Patrol of rivers, etc. ・Mobilization of flood-fighting and fire-fighting organizations ・Ordering residents, etc., to move out ・Reporting and publishing water levels ・Reporting levee breaches Role of the state government

Flood forecasting Director-General of Japan Meteorological Agency (JMA) ・In the event of the imminence of a flood or storm surge, the Director-General of JMA informs the Minister of Land, Infrastructure, Transport and Tourism and the prefectural governors concerned of the present state. Minister of Land, Infrastructure, Transport and Tourism ・Informs, jointly with the Director-General of JMA, for a class A river (excluding designated sections), the prefectural governors concerned of ①water level or discharge if the possibility of flooding is deemed high or ②water level or discharge, or the flood hazard area and the flood water depth if flooding has already occurred. Prefectural governors ・Communicates the information received as described above to the flood protection managers and stage gauge managers. Issuing flood watch advisories 7 Ministry of Land, Infrastructure, Transport and Tourism

1. Japan's basic flood protection system

2. Preparedness for major floods

・Past major floods and state-level efforts ・Role of MLIT

8 Ministry of Land, Infrastructure, Flood caused by Typhoon Kathleen (1947) Transport and Tourism

Inundation due to a breach in the right-bank levee of the in the Shinkawadori area in Azuma-mura (present-day Otone-machi), Prefecture Higashi-mura (present-day Otone-machi) Saitama Gunma Ibaraki Total

Tone River Dead 8 4 86 592 58 352 1,100 (persons)

Injured 138 1,394 315 23 550 2,420 (persons)

Tone River Number of completely or partially destroyed houses: 31,381 House inundation: 303,160 houses Farmland inundation: 176,789 ha

Flooding in Kurihashi-machi, Saitama

Naka River River ３５０ｍ

Satte-machi, Saitama, submerged in turbid water (Satte City)

Sept. 19 -ku Submerged Legend in 3 m water water depth: less than 50 cm water depth: 50 cm to 2 m water depth: 2 m or more

Tokyo 9 Ministry of Land, Infrastructure, Storm surge caused by Typhoon (1959) Transport and Tourism

Flood damage in Aichi and Mie prefectures caused by Ise Bay Typhoon City National total Aichi and Mie Shinkansen Number of people killed or missing 5,012 4,533 91% Number of injured people 69,538 63,670 92% Number of affected people J 1,887,723 1,110,057 59% way R ess Number of totally or partially destroyed houses xpr T 177,574 125,591 71% in E o ish k Me a Number of houses washed away 16,580 15,386 93% id Searching a stranded house o Number of flooded houses 359,178 196,256 55% L in e Farmland washed away or buried 14,662hectare 6,325ha 43% Farmland submerged 295,264hectare 89,503ha 32% City Estimated amount of damage ¥47,857,470,000 ¥13,189,080,000 30% Number of boats/ships washed away or sunk 2,481 2,069 83% T o m e i Kuwana E i x a p City s re n s a e s n Yoro-cho, Gifu (Web site of K i w a L Tokai City Chiryu City y Gifu Prefectural Government) R J People stranded on the second floor of a house City Chita City Okazaki City Anjo City S Takahama h R in ou City kan t e Handa City sen 1 Suzuka Tokoname City City 3 City Toyokawa City 2 Gamagori City e te in u L o e R s I City Ise Bay R Minami-ku, Nagoya City J (Ise Bay Typhoon Tsu City Record Book compiled by Nagoya City) Hisai City

Matsusaka City Inundation area 10 Ministry of Land, Infrastructure, History of river improvement Transport and Tourism

1945 1950 1955 1960 1965 19701975 19801985 1990 1995 2000 2005

1947 1959 1972 1982 1990 1995 2000 2004 Typhoon Kathleen Ise Bay Typhoon Heavy rain in July Typhoon No. 10 Eruption of Mt. Hanshin-Awaji Tokai Heavy Rain Typhoon No. 23 Number of people Number of people Number of people Number of people Unzendake Earthquake Number of people Number of people killed: 1,077 killed: 4,697 killed: 421 killed: 427 Number of people Number of people killed: killed: 10 killed: 95 killed: 38 6,310 Number of people Number of people Number of people Number of people Number of people Number of people Number of people Number of people injured: 1,547 injured: 38,921 injured: 1,056 injured: 1,175 injured: 12 injured: 43,188 injured: 118 injured: 721 Creation of a safe, secure and and secure safe, a of Creation disaster-resistant country Infrastructure Emergency improvement Five-year development in the wake of major post- flood control priority plan war floods programs Measures to cope with beyond-design-basis floods

Comprehensive flood Improvement of relatively small control measures rivers coordinated with urbanization

1964 revision of the River Act 1960 1997 revision of the River Act Establishment of systematic Erosion and Flood 1991 revision of the River Act Establishment of comprehensive river river management system Control Emergency Super levees (high-standard levees) system designed for flood control, water designed for flood control and Measures Act utilization and environmental conservation water utilization

2003 2001 revision of the Flood 1949 Protection Act Urban Flood Protection Act Flood Protection Act Establishment of inundation 2005 revision of the Flood hazard area system Protection Act Improvement of system for providing flood information 11 Ministry of Land, Infrastructure, Characteristics of flood damage in recent years Transport and Tourism

The area of inundation has decreased, but the amount of flood Watershed urbanization causes flood risk to increase. damage shows an increasing trend. As a result of railway and arterial road network construction, which began around The amount of flood damage is on the increase. 1960, watersheds today are crisscrossed with railways and roads. The resultant →Although the area of inundation had been on the decrease because of flood urbanization has caused the water retention and detention functions of the control measures, it has been showing a slightly increasing trend in recent watersheds to decline. years. Mainly because of the urbanization of flood-prone areas and the 1958 2004 increase in flood-vulnerable property, the amount of damage has been Percentage of urbanized area: Percentage of urbanized area: showing a tendency to increase. about 10% about 85% Population: about 450,000 Population: about 1,880,000 水害密度（万円／ha） Flood damage density (10,000 yen/ha) Property一般資産被害額(千億円) damage (100 billion yen) 小田急小 田原線 Nanbu南武線 Line東急東横Tokyu 線 Toyoko Line京 6,000 浸水面積１haあたり 6.0 Odakyu Line Line Kyuko Keihin Amount of property damage per ha of inundation area (2000 prices) Flooded水害区域面積(万ha) land area (10,000 ha) 東 Line Tokaido 浜 一般資産被害額（平成12年価格） 海 急 ５，５８５ 道 行 市営地下Municipal subway 鉄 線 線

5,000 5.0 Area of flooded Daini Keihin 宅地等の Property一般資産水害密度 damage density Line Natural land land in residential 第二京浜(Route 1) （浸水面積あたりの(amount of property damage per 横浜線 areas,水害区域面積 etc Urbanized land unit area of inundation)一般資産被害額） Example: 第一京浜Daiichi Keihin 4,000 4.0 basin (Route 15) Transportation各年代 間に network 整備さ developed れた交 通 in 網each period ３．９ As runoff increases, the time to peak runoff decreases. 3,000 3.0 Amount一般資産被害額 of property damage Peakピーク時流量 discharge Time from peak precipitation intensity fromTime peakprecipitation

2,000 2.0 After watershed Flood discharge 流域開発後urbanization 洪水流量は 約２倍にhas doubled.倍増 洪 Runoff 水 流 1,000 1.0 量 Peakピーク時流量 discharge

０．７ Before watershed 流域未開発時urbanization

The time to peak 0 0.0 ピーク発生時間discharge has は '7954 55 '80 56 '81 57 '82 58 '83 59 '8460 '85 61 '86 62 '87 63 '88 1 '89 2 '90 3 '91 4 5'92 6 '93 7'94 8 '95 9 '96 10 '97 11 '98 12 '99 13 '00 14 '0115 16'02 17 '03 18 '04 '05 '06 decreased約1/3に短縮 to 1/3. 昭和 平成 Infiltration Notes:注１）値は過去５箇年の平均値である。 1. Averages in the last five years 5５時間 hrs １０時間10 hrs １５時間15 hrs 注２）一般資産被害額及び水害密度には、営業停止損失を含む。2. The amount of property damage and flood damage density include business interruption loss. Time降雨のピーク時からの時間 from peak precipitation intensity 注３）出典：国土交通省河川局「H18水害統計」より。3. Source: 2006 Flood Statistics combined by River Bureau, Ministry of Land, Infrastructure, Transport and Tourism 注４）価格は平成１２年価格である。 4. 2000 prices Increasingly intensive land use (e.g., subways, underground streets) has given rise to new types of inundation damage such as flooding of underground spaces.

If submerged in water, even if only once, electronic Having absorbed water, insulation materials appliances are rendered useless. have become useless. Tokyo Metro's Azabu Juban Station (October, 2004) municipal subway (July, 2003) 12 Ministry of Land, Infrastructure, Increasing frequency of heavy rains: The trend is expected to continue. Transport and Tourism

Both hourly rainfall and daily rainfall tend to increase. In future, precipitation is likely to increase throughout the country.

400 Annual frequency of 50 mm/hour or more precipitation events (per 1,000 locations) Projections of increase in daily precipitation in 100 years 350 354

318 ① 1.24 300 Increase of 250 275 275 ② Tohoku 1.22 ② 245 about244 50% 245 229 232 ① 216 200 205 205 206 ③ Kanto 1.11 191 193 179 181 178 182 182※ 177 171 1998-2007 150 154 159 152 158 H10～19 ④ Hokuriku 1.14 144 149 130 238 events 1988-1997128 平均 回 100 104 107S63～H9 238(average) ⑤ Chubu 1.06 S511976-1987～62 95 177 events93 平均 177(average) 回 ④ 50 平均162162 events 回 ⑥ Kinki 1.07 (average) ③ 0 ⑦ Southern Kii 1.13 S H 10 '76515253545556575859606162631234567891011121314151617181920'77 '78 '79 ‘80 ‘81 ‘82 ‘83 ‘84 ‘85 ‘86 ‘87 ‘88 ‘89 ‘90 ‘91 ‘92 ‘93 ‘94 ‘95 ‘96 ‘97 ‘98 ‘99 ‘00 ‘01 ‘02 ‘03 ‘04 ‘05 ‘06 ‘07 ‘08 ⑧ Sanin 1.11 ⑧ ⑤ Annual frequency of 100 mm/hour or more precipitation events (per 1,000 locations) 8 ⑨ Setouchi 1.10 ⑨ ⑥ 7 ⑩ Southern ⑦ Increase of H101998-2007～19 1.11 ⑩ Ratio of increase in precipitation* S631988-1997～H9 3.7 events ⑪ Kyushu 1.07 ⑪ 5 about 100% 55 5 平均 3.7(average) 回 5 S511976-1987～62 2.0 events 3.7 1.2 times or more 4 1.8 events4 平均 2.0(average) 回 4 4 平均 1.8(average) 回 1.1-1.2 times 3 1.0-1.1 times 22 2 2 2 2 22 2 2 ２※ * Maximum daily precipitation 1 1 1 1 1 1 0 0 0 000 0 S51'76 52'77 53'78 54'79 55 56‘80 57‘81 58‘82 59‘83 60 61‘84 62‘85 63‘86 1‘87 2‘88 3 4H‘89 5‘90 6‘91 7‘92 8 9‘93 10‘94 11‘95 12 13‘96 14‘97 15‘98 16‘99 17 18‘00 19‘01 20‘02 ‘03 ‘04 ‘05 ‘06 ‘07 ‘08 The level of flood safety will decline because of a future increase in precipitation. For ・The annual frequency of precipitation events with different hourly precipitations example, in some regions such as Hokkaido and Tohoku, the target level of flood was calculated from AMeDAS data obtained from about 1,300 locations in Japan. 18 ・The 2008 data are data obtained on or before September 2, 2008. safety of 1/100 will decrease to about 1/30 so that the flood safety level will decrease Annual frequency of days with a daily precipitation of 200 mm or more to about 1/3 of the target level. 16

Flood safety level (return period) (return level safety Flood 100 14 Increase of about 50%

Number of daysyear per 3.5 days 5.1 days 年 12 D (1901-1930 average) (1978-2007 average) ecr 間 75 ease 合 10 計 8 日 50 数 6 １/３ 4 25 2 Plan Hokkaido Tohoku Kanto Hokuriku Kinki Kii Southern Sanin Setouchi Shikoku Southern Kyushu 0 計 北 東 関 北 Chubu 中 近 紀 山 瀬 四 九 0 画 海 北 東 陸 部 畿 伊 陰 戸 国 州 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 道 南 内 南 The annual frequency of days with a daily precipitation of 200 mm or more calculated from measurements obtained at 51 locations in Japan. Both values in each year (thin line) and 11-year moving averages (thick line) are shown. (JMA data) 部 部 13 Ministry of Land, Infrastructure, Consecutive occurrence of major flood and mass-movement disasters Transport and Tourism

Heavy rainfall events with a total rainfall exceeding 1,000 mm have occurred almost every year mainly in Kyushu, causing flood and mass-movement disasters. 2004 2005 ・Typhoon No. 14 (Sept. 4 to 6) caused heavy rains with a total rainfall of 1,000 mm or more in southern Kyushu. ・ A record number (10) of typhoons made landfall in Japan (three or more times as many typhoons as in the average year). ・ ・During Typhoon No. 10 (July to August), hourly rainfalls of more than 100 mm were observed in the Shikoku region. In A number of rivers including the Oyodo and Gokase rivers flood, causing serious damage in the Kyushu region. Prefecture, a total rainfall of more than 1,000 mm was recorded. ・In the Chugoku region, the bankful stage was exceeded in the Ota and other rivers. ・The Heavy Rain (July) caused a levee breach along the . Typhoon No. 23 (October) caused levee ◆Typhoon No. 14: Kyushu region: 19 people killed, 3 people missing, 3,960 houses flooded above floor level, breaches and overtopping along the Yura and Maruyama rivers, inflicting tremendous damage in , Hyogo and other 5,085 houses flooded below floor level parts of the Kinki region. Chugoku region: 4 people killed, 1,678 houses flooded above floor level, 2,969 houses ◆Fukui Heavy Rain: 4 people killed, 4,052 houses flooded above floor level, 9,674 houses flooded below floor level, etc. flooded below floor level ◆Typhoon No. 23: 43 people killed, 13,041 houses flooded above floor level Distribution of rainfall caused by Typhoon No. 14 Flooding of the Oyodo River Debris flow in the Kamishiiba Stranded bus in a flooded area Funato, Tsuno-cho, Takaoka- ( City, Miyazaki) area (Shiiba-son, Miyazaki) gun, Kochi Pref. 870mm Distribution of rainfall caused by Typhoon No. 10

Typhoon台風6号 No. 6

Typhoon台風15号 No. 15 Typhoon台風4号 No. 4

Typhoon台風21号 No. 21 バス

Typhoon台風16号 No. 16

Typhoon台風18号 No. 18 Mikado, Misato-cho,

Typhoon台風23号 No. 23 Higashi-usuki-gun, Ebino, Ebino City, Miyazaki Pref. 1,322mm Fukuhara Asahi, Miyagawa, Typhoon台風22号 No. 22 Miyazaki Pref. 1,307mm

Kamikatsu-cho, Tokushima Miyagawa-mura, Typhoon No. 11 台風11号 50 100 200 400 600 800 1,000 Pref. 1,132mm Mie Pref. 1,200mm Typhoon台風10号 No. 10 Flooding of the 50 100 200 400 600 800 1,000 (Maizuru City, Kyoto) 2007 2006 ・Typhoon No. 4 (July 2 to 17) caused a total rainfall of more than 1,000 mm in the Kyushu region. Rainfalls more than two times as much as the monthly average were recorded in many areas. ・In parts of the Kyushu region, total rainfalls in seven days from July 18 to July 24 of more than ・The Midori and other rivers flooded to cause tremendous inundation damage in many areas. 1,200 mm were recorded. The and Komenotsu rivers flooded, causing serious damage in ◆Typhoon No. 4: 3 people killed, 169 houses flooded above floor level, 1,152 houses flooded below floor level southern Kyushu. ・A strong bai-u front in July remained stationary over a large area including the Kyushu and Hokuriku regions, and the heavy rains induced by this front caused floods in many areas. Rainfall distribution on July 2 to 17 ◆July Heavy Rains: 5 people killed, 899 houses flooded above floor level, 2,674 houses flooded Ebino, Ebino City, Mitate, Hinokage-cho, Pref. Miyazaki Pref. below floor level 1,105 mm (130%) 1,058 mm (230%) Distribution of rainfall caused by July Heavy Rains Tawarayama, Nishihara- Yanase, Umaji- Okuchi City, Flooding of the Midori River mura, Pref. mura, Kochi Pref. Kagoshima Pref. (Kosa-machi, Kumamoto) 1,080 mm (160%) 936 mm (160%) Okuchi: 1,122 mm

Tashiro, Kinko-cho, Ikegawa, Niyodogawa-cho, Ebino City, Miyazaki Pref. Debris flow in the Futagawa area Kagoshima Pref. Kochi Pref. Debris flow in the Ebino: 1,281 mm 1,018 mm (270%) 929 mm (210%) (Satsuma-cho, Kagoshima) Shimodenakama area (Tarumizu City, Kagoshima) Flood flow in the Midori River 100 200 300 400 600 800 1,000 (Hishikari-cho, Kagoshima) (Kosa-machi, Kumamoto) 14 Ministry of Land, Infrastructure, Damage caused by localized heavy rains Transport and Tourism

Flood damage in 2008 The heavy rains on July 28, 2008, and at the end of August brought about localized heavy rains with an hourly rainfall of more than 100 mm and caused inundation damage in many parts of the country.

Damage caused by the flooding of the Asano River in July, 2008, Flood damage in Okazaki City, , in Ishikawa Prefecture and Nanto City in Prefecture caused by the heavy rains at the end of August, 2008 ieRiver Hime uoeRiver Kurobe

Asano River Asano A record hourly rainfall of yb River Iga

h River Sho 146.5 mm (previous Shonai River

Hourly rainfalls of 132 mm and River Kakehashi 一宮 114 mm were recorded at the River Tedori record: 55 mm) was Koinzemi raingauge station observed at the Okazaki oaj River Joganji (Nanto City) and the River Kuzuryu raingauge station (Okazaki Okazaki Shibaharabashi raingauge station City, Aichi Pref.), and Kumozu River another record rainfall of ( City), respectively. Koinzemi River Jinzu Shibaharabashi 120 mm (previous record: 76 mm) was observed at ●Raingauge station ●Raingauge station the Ichinomiya raingauge * Koinzemi raingauge station (MLIT) station (Ichinomiya City, * Shibaharabashi raingauge station (Ishikawa Pref.) Aichi Pref.).

Driftwood accumulated at the Asanogawa Bridge (Kanazawa City) Two houses partially destroyed by a landslide (Nanto City) Inundation in Iga- In Kanazawa City, the flooding of the Asano River left 507 houses flooded cho, Okazaki City above floor level and 1,476 houses flooded below floor level. A total of 55 landslides occurred in Ishikawa and Toyama prefectures, causing damage to In Okazaki City, 620 houses were flooded above floor level, and 705 houses were 20 houses. flooded below floor level. 159 Ministry of Land, Infrastructure, Transport and Tourism

1. Japan's basic flood protection system

2. Preparedness for major floods

・Past major floods and state-level efforts ・Role of MLIT

16 Ministry of Land, Infrastructure, MLIT's emergency response system to cope with major floods Transport and Tourism

Emergency status ・In the case where an organization such as a regional development bureau has moved to the emergency status and serious damage has occurred or may occur ・In the case where extensive windstorm or flood damage is almost certain to occur and in any of the following cases: (a) The likelihood of occurrence of a levee breach in a particular river section is high or such a breach has already occurred and the occurrence of extensive damage is thought likely. (b) Extensive damage due to a storm surge is almost certain to occur, judging from the magnitude, intensity, course and speed of a typhoon and tide level and other information. (c) Extensive damage due to mass movement, etc., has occurred and the occurrence of further damage due to mass movement, etc., is thought likely. (d) Serious human suffering or property damage other than those mentioned above has occurred or may occur.

Alert status ・An organization such as a regional development bureau has moved to the alert status. ・Transportation facilities that could affect many passengers have been damaged because of the approach, landfall or other behavior of a typhoon.

Watch status ・An organization such as a regional development bureau has moved to the watch status. ・Transportation systems in two or more prefectures have been rendered inoperable because of the approach, landfall or other behavior of a typhoon. 17 Ministry of Land, Infrastructure, Role of MLIT Transport and Tourism

・Mobilizing leaders, staff members and related department members 14th floor, Building No. 2 ・Observing and distributing meteorological information, site

images, etc. Front monitor panel ・Collecting and sharing information (integrating damage TV conference information) ・Exchanging information with ministers' offices, other ministries and agencies, local departments, etc. ・Providing information to the public ・Regional assistance, assistance to local governments

Fax connected to Central Photocopier Disaster Prevention Council

Scanner Monitor control Fax connected to Color printer panel ministers' offices Monochrome copier

MLIT's disaster prevention center Plasma TV FAX FAX 18FAX Ministry of Land, Infrastructure, MLIT's response to a major emergency (state level response to the 2004 flood (Typhoon No. 23)) Transport and Tourism

○○OnOn OctoberOctober 20,20, 2004,2004, TyphoonTyphoon No.No. 2323 causedcaused seriousserious damagedamage inin HyogoHyogo PrefecturePrefecture andand thethe northernnorthern partpart ofof KyotoKyoto Prefecture.Prefecture. RiverRiver leveeslevees werewere breachedbreached atat severalseveral locations.locations. ForFor thethe MLIT-managedMLIT-managed MaruyamaMaruyama River,River, wherewhere floodflood damagedamage waswas particularlyparticularly severe,severe, temporarytemporary restorationrestoration worksworks werewere carriedcarried outout withwith thethe assistanceassistance ofof nearbynearby regionalregional developmentdevelopment bureausbureaus inin orderorder toto guardguard againstagainst futurefuture flooding.flooding. TemporaryTemporary restorationrestoration worksworks atat twotwo sitessites werewere completedcompleted inin fivefive days.days. Levee breaches along the (2 locations) Around-the-clock work for Torii Bridge temporary restoration of levees

Tachino Bridge Emergency investigation Vehicle for using a helicopter emergency use MLIT operation Levee damage Levee damage Levee breach site: around 5.4 km point Levee breach site: around 13.2 km point Pumper truck on the left bank of the Izushi River River Maruyama on the right bank of the Maruyama River 4 pumper trucks uaRiver Yura

7 pumper trucks × × 4 pumper trucks Experts were dispatched to Toyooka Inundation in the city of Toyooka MLIT City, etc. (steep slope sites) 13 pumper trucks

Twenty-eight pumper trucks were called in for drainage work. Kinki Regional Development Bureau: 13 pumpers Chubu Regional Development Bureau: 4 pumpers The Yura River, too, flooded in . In Maizuru City, a tour Site visit by MLIT Minister Twenty-eight pumper trucks were Hokuriku Regional Development Bureau: 4 pumpers bus was submerged on Route 175, and 37 passengers were stranded on Kazuo Kitagawa called in from around the country Chugoku Regional Development Bureau: 7 pumpers the roof of the bus. About 11 hours later, the passengers were rescued by a Japan Coast Guard rescue team. Temporary restoration of the MLIT-managed river sections (two levee breach sites) were completed in five days with the assistance of nearby regional development bureaus. The levee breaches in the sections managed by Hyogo Prefecture (four sites) were smaller than the breach sites in the MLIT-managed sections, but the temporary restoration of the four breached sections took 17 days. 19 Ministry of Land, Infrastructure, MLIT's assistance to prefectures in case of a major disaster (- Heavy Rains in 2004) Transport and Tourism

ToTo copecope withwith thethe floodingflooding ofof thethe KariyataKariyata and and IkarashiIkarashi rivers rivers managedmanaged byby NiigataNiigata Prefecture,Prefecture, pumpumperper truckstrucks andand mobilemobile lightinglighting systemssystems werewere dispatcheddispatched notnot onlyonly fromfrom withiwithinn thethe regionregion coveredcovered byby thethe HokurikuHokuriku ReRegionalgional DevelopmentDevelopment BureBureauau butbut alsoalso fromfrom thethe Tohoku,Tohoku, KantoKanto andand ChubuChubu regionalregional developmentdevelopment bureaus.bureaus.

Dispatched emergency equipment

Pumper truck 36 units Breakdow n 20 units Hokuriku Regional Dev elopment Bureau Tohoku Regional Dev elopment Bureau 5 units Kanto Regional Dev elopment Bureau 8 units

Chubu Regional Dev elopment Bureau 3 units River Ikarashi Mobile lighting sy stem 17 units River Kariyata

Breakdow n River Shinano 11 units Hokuriku Regional Dev elopment Bureau Pumper truck in action River Saruhashi Tohoku Regional Dev elopment Bureau 3 units Kanto Regional Dev elopment Bureau 3 units Satellite communications v ehicle 1 unit Mobile command v ehicle 2 units Standby support v ehicle 3 units Ku-SAT 4 units Portable helicopter TV receiver station 1 unit Truck-mounted drain cleaning machine 1 unit Truck-mounted roadside gutter cleaning 1 unit machine Nighttime work using a mobile lighting system

Inundation damage mitigation by use of pumper trucks Inundation areas and pumper truck locations

○12 municipalities in Legend (Sanjo City, Mitsuke City, Nagaoka City, Nakanoshima-machi, Sakae-machi, Niigata City, Gosen City, Tsubame City, Inundation area on July 14 Mishima-machi, Bunsui-machi, Tagami-machi, Koide-machi) Inundation area at 16:00 on July 15 Pumper truck location ○3 municipalities in Fukushima Prefecture (Kitakata City, Aizubange-machi, Shiokawa-machi) Inundation area at 16:00 on July 18 20 Ministry of Land, Infrastructure, MLIT's assistance to local governments in case of emergency Transport and Tourism ◆ Assistance process flow Prevention of further spread of Dissemination of information on options Prevention of further spread of Timely and effective support and Dissemination of information on options damage in the affected area and early Timely and effective support and for support and assistance to local damage in the affected area and early assistance to local governments, etc. for support and assistance to local assistance to local governments, etc. governments, etc., in the affected area restorationrestoration and and recovery recovery governments, etc., in the affected area ◆ Assistance options ①Providing images, maps, information, etc. (e.g., providing images of ⑤Shelters, relief goods, etc. (e.g., providing shelters, using "Michi no the affected area) Eki" (stopovers along national roads)) ②Risk evaluation, etc. (e.g., inspection of mass movement risk sites) ⑥Housing (e.g., assistance for the construction of temporary housing) ③Damage survey (e.g., assistance for damage surveys, disaster ⑦Post-disaster restoration (e.g., technical assistance for post-disaster prevention expert assistance for surveys) restoration) ⑧Recovery (e.g., assistance for recovery planning, assistance for ④Support (e.g., lending emergency vehicles, dispatching experts) tourism campaigns) ◆ Currently available emergency resources Adopted by MLIT's disaster prevention council on June 27, 2005 Mobile command vehicle Emergency helicopter Satellite communications vehicle Mobile lighting system 57 vehicles 8 helicopters 53 vehicles 211 units

Portable image transmission system: Ku-sat 327 sets

21 Ministry of Land, Infrastructure, Transport and Tourism Establishment of Technical Emergency Control Force (TEC-FORCE*) ※Technical Emergency Control Force

Support system for Niigata-Fukushima Heavy Rains in 2004 PurposePurpose ・Prompt collection of information on the state of damage in a major natural disaster and early restoration of the affected area Occurrence大規模水害の発生 of a major flood ・Smooth and timely provision of technical assistance to local governments, etc. 地方整備局Regional development bureau Drainage operation by ActivitiesActivities use of pumper truck ●Prompt collection of information on the state of damage Pumper trucks ●Early restoration of infrastructure ・Faster initiation of response activities ・Intensive response by a team of experts ・Improvement and strengthening of technical guidance concerning restoration measures Helicopter ●Prevention of secondary damage Helicopter-based survey ・Sophisticated technical guidance related to damage Mobile lighting systems sites ・Emergency measures (planning and implementation) ・Risk level prediction (judgment on evacuation) ●Other emergency response measures ・Coordination of emergency transportation

Nighttime work using a mobile lighting system TEC-FORCETEC-FORCE membermember appointmentappointment statusstatus ・Personnel of MLIT, regional development bureaus, district transport bureaus, National Institute for Land and Infrastructure Necessity of regional support system Management, etc. Necessity of regional support system Total: 2,563 members (as of October 1, 2008) 22 Ministry of Land, Infrastructure, Activities of TEC-FORCE Transport and Tourism

The TEC-FORCE was dispatched after the Iwate-Miyagi Nairiku Earthquake (from June 14, i.e., the day of the earthquake, to July 22) and the Iwate-ken Engan Hokubu Earthquake (from July 24, i.e., the day of the earthquake, to July 29) to investigate the affected areas, provide guidance on restoration methods, take secondary damage prevention measures.

Activity results Iwate-Miyagi Nairiku Earthquake: 515 vehicle-days, 1,499 person-days Iwate-ken Engan Hokubu Earthquake: 4 vehicle-days, 381 person-days

MLIT

Telecommunications team

Advance team (helicopter-based survey)

Blocked river channel Specialized technical guidance team (river channel blocking) 23 Ministry of Land, Infrastructure, Direction of future MLIT efforts Transport and Tourism

ClarificationClarification of of goal: goal: Working Working toward toward "zero "zero victims" victims" Minimization of damage CompleteComplete protection protection from from increasingly increasingly severe severe floods, floods, etc., etc., is is difficult difficult to to achieve. achieve. ・ ・StudiesStudies are are conducted conducted on on ways ways to to achieve achieve "zero "zero victims." victims." ・ ・InIn the the areas areas where where key key state state functions functions are are concentrated, concentrated, priority priority measures measures such such as as measures measures to to prevent prevent complete complete impairmentimpairment of of the the state state functions functions are are taken. taken. Measures to cope with growing external forces

（Multi-layered flood control measures） （Phased safety measures against storm surges and ・In addition to the flood control measures designed to ensure upgraded measures against ongoing coastal erosion） safety from the design-basis discharge, watershed-based ・In order to ensure safety from storm surges, coastal structures are measures are also taken to ensure safety from growing external raised when, for example, they are reconstructed to guard against forces. growing external forces.

赤字：現在のThe present level治水安全度 of flood safety is shown in red. The future level青字：将来の治水安全度 of flood safety is shown in blue. ・From the viewpoint of protection from ongoing coastal erosion, effort 現在 将来（例えば、Future (100 years100 later,年後をイメージ） for example) is made to implement comprehensive sediment control measures. Third stage 高 Height ①Freeboard ①余裕高 1/150 1/150 ②Sea level rise 第3段階 さ ②海面上昇分 ③Allowance for ③海面の expected sea level 上昇予測分 Allowance for higher 現在目標 Upgrading増加する facilities外力 for rise Present goal of The current target level of dealing with Second stage ④台風の強度増加にstorm台風の強度増加に surge level due to としている 現在目標としている に対し、施設 ④Allowance for higher flood safety will fall increased external ●Adaptation 伴う高潮上昇分increased伴う高潮の上昇分 typhoon flood safety 治水安全度は降雨量の 整備の再設定 第storm2 surge段階 level due 治水安全度 considerably because of forces measures intensity 増により著しく低下 to increased typhoon increased precipitation. ●施設による relying on Present現在 intensity facilities適応策 ①Freeboard 第１段階 海面の上昇予測分Expected sea level =Δh2 1/70 First stage ②Sea level rise rise = Δh2 Allowance for expected ①余裕高 海面の上昇分 ③Allowance②海面上昇分 for sea level rise 現在確保 目標としているTarget level of Present level of expected③海面の sea Allowance for higher storm surge level due to 治水安全度flood safety 台風の強度増加に伴う高潮の上昇分＝Δ されている The目標としていた current target ①①余裕高Freeboard 上昇予測分 h3 flood safety level of flood safety 1/40 level rise increased typhoon intensity =Δh3 治水安全度の ②海面上昇分 治水安全度 will fall in 100 ②Sea level rise 100年後の評価 確保されている years. 1/20 Accomplished確保されている level of 確保されていた 治水安全度 ①余裕高 Expected sea level The accomplished level flood safety Sea level rise前回の更新時からの海面上昇分 since last reconstruction = Δh1 Δ １ Freeboard 海面の上昇予測分=Δh2 = h of治水安全度 flood safetyの低下 will fall. 余裕高 ①Freeboard rise = Δh2 ＝Δz Sea前回の更新時からの海面上昇分 level rise since last reconstruction == Δh1h１ ●Watershed-based●総合治水対策等 measures, ● ●地域づくりと一体となった適応策 Adaptation measures integrated with Sea前回の更新時からの海面上昇分 level rise since last reconstruction == Δh1h１ etc., among comprehensive community●危機管理対応を planning中心とした適応策 measures flood control measures ●Adaptation measures centered around risk Time時間 management Multi-layered flood control measures Service耐用年数 life Service耐用年数 life Service耐用年数 life Reconstruction更新 Service耐用年数 life 更新 Reconstruction更新 =＝Δｔ Δt Reconstruction =＝Δｔ Δt =＝Δｔ Δt =＝Δｔ Δt Phased upgrading of storm surge protection measures 24 Ministry of Land, Infrastructure, River improvement plan incorporating measures against climate change Transport and Tourism

zA road map indicating the procedures for adaptation measures is prepared, taking the impact of climate change into consideration. zThe potential disaster risk of the watershed under consideration is evaluated by monitoring the present state of climate change and predicting the future state. zThe evaluated disaster risk is shared in the watershed to consider adaptation measures to be taken and reflect the findings on the road map. zAdaptation measures to be taken are prioritized according to the degree of necessity, and effort is made to achieve mainstreaming of climate change adaptation.

River improvement plan adapted to cope with climate change

DDDoo ImplementingImplementing CCCheckheck MonitoringMonitoring ofof adaptationadaptation measuresmeasures EvaluatingEvaluating adaptationadaptation climate change measuresmeasures throughthrough climate change lan Implementing measures in PPPlan floodflood riskrisk evaluationevaluation Devising adaptation cooperation with the Devising adaptation zAnalyzing and organizations concerned z measuresmeasures andand preparingpreparing Establishing a flood risk evaluating (assessing) andand modifyingmodifying aa roadroad mapmap evaluation method and the impact of climate reviewing the flood change control economics study zDevising adaptation measures to zPreparing a global cope with climate change Actionction warming report in AA cooperation with the ReviewingReviewing adaptationadaptation Japan Meteorological zAdaptive response according to the measures and the measures and the Agency road map roadroad mapmap Considering additions or changes to adaptation measures and the road map on the basis of evaluation results 25 Ministry of Land, Infrastructure, Example of flood risk analysis Transport and Tourism Concepts of flood risk analysis associated with different phenomena

River flooding due to typhoon-induced heavy rains or torrential downpours and inundation due to localized heavy rains are different phenomena that require different zoning approaches for flood risk analysis.

Tasks Typhoon-induced heavy rain, torrential Torrential downpour, localized heavy rain performed in downpour zReview of inundation damage records inundation- zReview of past floods zInundation simulation AnalysisAnalysis prone area zRunoff analysis and inundation analysis zZoning into drainage areas and mapping and zZoning into inundation blocks flooding areas （（taskstasks thatthat areare usuallyusually notnot perperformedformed forfor inundation-proneinundation-prone areaarea （tasks that are usually not performed for inundation-prone area hazard mapping）） mapping） mapping

Classification of inundation patterns Zoned into drainage areas and inundation areas Ａ Ａ Ｂ Ｂ

ST Ａ

Ａ Ｂ Ｂ Ｃ

Note: Risk map Inundation-prone prepared for Higher risk area map illustration Ｄ Ｅ purposes only

Runoff analysis and Higher risk inundation analysis Ｆ Ｐ Source: Data prepared for the fifth session of the Special Board of Inquiry on Measures against Major Floods Risk map (prepared for illustration purposes only) Risk map (prepared for illustration purposes only) 26 Ministry of Land, Infrastructure, Example of flood risk analysis Transport and Tourism Road mapping by use of flood risk evaluation A road map indicating the adaptation measures to be taken and procedures to be followed for different types of inundation and different blocks is prepared and shared within the watershed. 他の氾濫形態Comparison betweenとの比較 different types of inundation Road map (typical example) Note: Prepared【注：イメージ for 図】 Type氾濫形態 of inundation④ ④ illustration purposes only Type氾濫形態 of inundation⑤ ⑤ Target level of Ａ Ａ Type of Present Ｂ Block Place name damage risk 30 Planned facilities Facility plan (1-10 years) Facility plan (11-30 years) Watershed goal Ｂ Type of氾濫形態 inundation⑥⑥ inundation damage risk years later ST AAA Town, Ａ Right Type of inundation① Type氾濫形態 of inundation① ① Ａ BBB City Green Green bank Ａ Ｂ Type of inundation② Ａ CCC Town, ①Improvement Ｂ DDD City Levee reinforcement measures are Ｃ taken in order to Yellow Blue Road embankment lower the risk Type氾濫形態 of inundation② ② level of each Disaster prevention station Ｄ Ｅ block 30 years Type ofinundation 氾 濫 Ｂ EEE Town, later by at least 形 Levee reinforcement FFF City one level. risk Higher リ 態 Ｆ ③ Yellow Green ス Ｐ ②(If the goal ク Road embankment 増 ③ mentioned in ① Ｃ GGG Town, is not achieved) HHH City Road embankment Nonstructural Pink Green measures are Flood control reservoir upgraded so that the safety III Town, Ｄ Green Blue Problems (tasks) JJJ City level of higher- Problems (tasks) flood-risk blocks KKK Town, Ｅ Red Green Drainage pump can be raised. 1.1. FindingFinding waysways toto evaluateevaluate LLL City the level of safety Ｆ MMM Town, Pink Yellow Drainage pump the level of safety NNN City Type of inundation ③ Ａ OOO Town, 2.2. IdentifyingIdentifying andand developingdeveloping PPP City Levee reinforcement Red Green evaluationevaluation itemsitems andand Drainage pump methodsmethods neededneeded toto Type of inundation ④ QQQ Town, Left Ａ Green Green bank RRR City measuremeasure thethe degreedegree ofof SSS Town, Ｂ YellowYellow Flood control reservoir TTT City achievementachievement ofof suchsuch Type of inundation⑤ UUU Town, Ａ YellowBlue Levee reinforcement goalsgoals asas "zero"zero victim"victim" andand VVV City WWW Town, "the prevention of Ｂ PinkYellow Drainage pump "the prevention of XXX City Type of inundation⑥ YYY Town, paralysisparalysis ofof thethe centralcentral Ａ YellowBlue Levee reinforcement ZZZ City functionsfunctions ofof thethe state"state" Ｂ AAA Town, PinkYellow Drainage pump BBB City 3.3. FindingFinding waysways toto evaluateevaluate ：area that satisfies certain conditions in connection with nonstructural measures for disaster variousvarious risksrisks resistance enhancement comprehensivelycomprehensively Examples: the existence of a system for achieving evacuation in 30 minutes after receiving notice, the implementation of neighborhood associations' disaster prevention drills 27 Ministry of Land, Infrastructure, Establishment of flood forecast centers (provisional name) Transport and Tourism

◇In order to achieve the "zero victim" goal in the face of increasingly intense floods and localized heavy rains caused by climate change, flood forecast centers (provisional name) will be established in regional development bureaus to strengthen risk management measures in, for example, monitoring floods and providing information to municipal governments, the mass media, etc. ◇Flood forecast centers are to perform such tasks as climate change monitoring, flood risk evaluation and the development of an advanced flood prediction system.

Strengthening flood-monitoring and information-providing capability Climate change monitoring and flood risk evaluation

・High-accuracy weather radar systems and flood prediction systems are used for flood monitoring and information is ・The effects of increases and intensification of floods caused by climate change on provided by use of a variety of means of communication in order to better help municipal governments and the public people's daily life and the socio-economic conditions are identified through climate make appropriate judgments and take appropriate actions. change monitoring and flood risk evaluation. Example prepared for illustration purposes only

例）災害による犠牲者Example: projectionの予測 of flood victims

Ｂ 入間台地 Ａ 潜在的犠牲者 Potential victim index イメージ 発生指数

Flood prediction riskHigher リ Ｃ ス ク Real-time flood risk 増

Ｄ Radar Ｅ CCTV camera images Flooding analysis Impact and vulnerability observation 氾濫解 析を実・類 施 型 区 分 evaluation Ｆ

））） Development of an advanced flood prediction system Flood forecast center IC tag ・With the aim of proper risk management consistent throughout the watershed, a flood (provisional name) prediction system for estimating flood distribution patterns, flood risk including landside flooding risk, real-time flooding patterns, etc., will be developed. Emergency warning device

Left: Distributed runoff model (prepared for illustration purposes only) Delivering emergency alarm MLIT-managed section Terrestrial digital Center: Watershed-by-watershed flood risk representation (prepared for messages by email Designated section illustration purposes only) media broadcasting One-segment Right: Result of high-accuracy flooding simulation (prepared for illustration broadcasting purposes only) 28