1:25,000 scale topographic maps
• Largest scale base maps that cover whole land of Japan Topographic mapping using satellite images • Total: 4,355 sheets
• 1 sheet covers: longitude 7.5 min. latitude 5 min. (about 100km2)
Geospatial Information Authority of Japan 3
Fundamental maps in Japan Photogrammetry
Paper-based maps - Scale: 1:10,000 ~ 1:5,000,000 - Mainly: 1:25,000 scale topographic map
Digital maps “Kunikaze III” - Digital Japan Basic Maps (Map Information) - Map image - Spatial data framework (2500, 25000) - Etc.
Providing - Publishing (paper, CD-ROM, etc.) - Browse via the Internet - Download through the Internet (Map Image)
2 Aerial photographs (with 60% overwrapping) 4
1 2 Flight course Advanced Land Observing Satellite(ALOS)
㻢㻜㻑㻌㼛㼢㼑㼞㼣㼞㼍㼜㻌㼎㼑㼠㼣㼑㼑㼚㻌㼚㼑㼕㼓㼔㼎㼛㼞㼕㼚㼓㻌㼜㼔㼛㼠㼛 PRISM 2.5m-spatial resolution 㻟㻜㻑㻌㼛㼢㼑㼞㼣㼞㼍㼜㻌㼎㼑㼠㼣㼑㼑㼚㻌㼚㼑㼕㼓㼔㼎㼛㼞㼕㼚㼓㻌㼏㼛㼡㼞㼟㼑 three optical system 㻢㻜㻑 Panchromatic sensor Launch : January 24th in 2006
AVNIR-2 Missions 10m-spatial resolution •cartography Multi-band(BGRNIR䠅sensor 㻟㻜㻑 •regional observation •disaster monitoring •resource surveying PALSAR 10m-spatial resolution L-band SAR
From JAXA HP
5 7
Photogrammetry -Principle- Comparison of aerial photo & satellite image
Using Aerial Photograph ALOS PRISM plotter Resolution 40cm 2.5m Interval of 1-5 year (GSI) 46 days Images Shooting Shooting 5km㽢5km 35km X 35km Area 䠄Scale 1:20,000䠅 35km X 70km Others Hard to take at Hard to interpret isolated islands, small structures & volcanoes etc. point features 3D model (lighthouses, towers, road dividers etc.)
6 8
3 4 Example of update: road ALOS/PRISM 䠄35km㽢35km䠅
Areal Photograph (1:30,000)
Overwrap
1:25,000 Map Sheet
©JAXA ©JAXA
9 11
Comparison of cost Example of update: large buildings
Cost (US Dollar) Size (km) Cost / km2 Resolution (m) Aerial photo 7 29.00 0.6 QuickBird 2,304 8 36.00 0.6 IKONOS 1,375 5 55.00 0.8 SPOT 10,290 60 2.86 2.5 ALOS 500500 3535 0.410.41 2.5
ͤAerial photo’s scale is 1/30,000, scanning pitch is 21μm
©JAXA
10 12
5 6 Example of update: large buildings
Coastline changes
GCP Collecting
©JA XA
©JAXA 13 15
PRISM 60-6100 Sep-2007 Mapping / Compilation
Isolate island located 1,200 km south of Tokyo Difficult to reach the photogrammetric aircraft Tokyo Many landform changes caused by Tsukuba
volcanic activity ©JAXA Topographic map has not updated since 1982 Can take full
advantage of Io To PRISM image
14 Published 1982 Revised 2007 16
7 8 Accuracy improvement of Antarctic map
Showa Base
©JAXA
©JAXA 17
References
• Bulletin of the GSI Vol.56 (PDF file can be downloaded at: http://www.gsi.go.jp/ENGLISH/Bulletin56.html)
– Revising 1:25,000-Scale Topographic Maps Using ALOS/PRISM Imagery Yuichi UCHIYAMA, Misuzu HONDA, Yoshiyuki MIZUTA, Koji OTSUKA, Takayuki ISHIZEKI, Takaki OKATANI and Eiichi TAMURA
– Verification of Topographic Road Centerline Data Using ALOS/PRISM Images: Implementation Hidenori FUJIMURA, Hidekazu MINAMI, Takenori SATO and Takahiro SHIMONO
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9
Outline of Musashi Canal Reconstruction Project Musashi Canal
Project outline Niigata Fukushima The Musashi Canal is an open channel of about 14.5 km connecting the Tone River and the Prefecture Prefecture Watershed Ara River. Shinano boundary River { Location: Gyoda City and Konosu City, Saitama Prefecture (Musashi Nagano The water to be used as city and industrial water in Tokyo and Saitama Prefecture is Canal connecting the Tone River and the Ara River) Prefecture Lake Chuzenji withdrawn through the Tone Weir, and conveyed to the Arakawa River. The water to be used Naka River to improve the quality of the water of the Sumida River is also conveyed. { Objectives: • Restoration of the function of steady flow Agatsuma Gunma Utsunomiya River Prefecture Tochigi Supply of water for urban areas through the Musashi Canal Prefecture • Securement and reinforcement of the function of inner drainage Maebashi W a tar Mito Karasu as e R River iv • Improvement of the water quality of the Ara River System Tone River er r Population of e
v Tone Weir Omoi River
i Ibaraki Supplied areas
R a Kinu River d the supplied areas
a Prefecture a
nn n
a Musashi Canal a m 20 cities and 8 towns
{ Numerical data (on reconstruction) K Ara River i Saitama Pref.
Tsuchiura h Saitama Pref.
Kasumigaura s
a About 13 million people K Main canal: A portion of 14.5 m in length reconstructed Chichibu 3 18 wards and 18 cities Saitama ver Tap water: 3.498 m /s Tokyo e Ri 3 Prefecture Ton 3 Sections: 43.2 m /s from the diversion works Saitama Industrial water: 1.100 m /s * The number of supplied areas is as of the end of March 2008. (starting point) to Motoarakawa Akigase Intake Weir * The population of the supplied areas indicates the total population of Tokyo the administrative areas where water is supplied, as of the end of
Tokyo RiverEdo 3 Ta a Tone River ma NakaRiver m March 2008. 50.0 m /s from Motoarakawa to Arakawa Kofu Ri a v Chiba h Yamanashi er ri u Tokyo Bay k Prefecture ju
(terminating point) Weir Tone u K Weir Tone Ara River
Pacific Ocean SagamiRiver r
Siphons: Six Yokohama SumidaRiver
e Tokyo
v
i
Kanagawa R
Mt. Fuji u
Flood gates: Three (including one new flood gate) s
Prefecture t 3
i b Tap water: 24.855 m /s Fuji River Fuji TsurumiRiver Outlets: Six (including two new outlets) O YoroRiver 3 Chiba Industrial water: 0.980 m /s Drainage pumping station: Up to 50 m3/s Prefecture Diversion works Other facilities: Drainage sluice pipes (1 natural drainage pipe and 1 forced drainage pipe), administrative facilities, etc. The percentage of water conveyed by the Musashi Canal to the { Project cost: About ¥70 billion total amount ofof waterwater suppliedsupplied inin thethe waterwater supplysupply areaarea
Saitama Pref. Water provided by Tokyo Water provided by { Construction period: From 1992 to 2015 the Musashi Canal: the Musashi Canal: GyodaCanal GyodaCanal Saitama Canal About 25% About 47% { Current status: Project not required to be verified 20 cities and 18 wards and 8 towns: 18 cities: About 14 m3/s About 53 m3/s Minumadai Minumadai Musashi Canal Musashi Musashi Canal Musashi 1 2
Prepared by the Musashi Canal Reconstruction Office, the Incorporated Administrative Agency Japan Water Agency 1 based on the Water Supply Statistics 2007 (Health Service Bureau, Ministry of Health, Labour and Welfare) 2 Current Musashi Canal Current Musashi Canal (dilapidated facilities, etc) Dilapidation has caused damage to water channels, suspended water conveyance, Typical cross section of the current Musashi Canal Typical cross section of the current Musashi Canal and increased chances for the occurrence of accidents caused by third parties. ϹЂ
4,000 8,000 Administrative road Administrative road 16,700 400 Design water level Embankment Embankment 1:1.5 1:1.5
2,500 Current ground line Weep hole 8,000
Ballasting at the Lateral drain bottom slab 150 6,000 Damaged lining panels Leakage through the joints of lining panels Left side underdrain pipe Right side underdrain pipe (point of 8,885 m, below the left band of the Namiki Bridge) (near the point of 2,500 m, left bank side) Transverse drain Center underdrain at the bottom slab Relation with nearby * Design section at the time of Relation with nearby constructing the Musashi Canal facilities Joetsu Shinkansen Line Kawazura JR Takasaki Line Water Gate Tone Weir Adachi North Drain Sama Water Gate
Nukata Drainage Minumadai National Hoshi Chichibu Oshi Pumping Station Tone River Canal Highway Motoara River River Railway River Ara River Route 125 3 4 14.5 km Raised bottom slab due to uneven settlement Deformation caused by sinkage 3 (point of 13,250 m, under the Sanmai Bridge) (near the point of 13,200 m, left bank side) 4 Current Musashi Canal (lowered passing water capacity due to sinkage) Current Musashi Canal: Insufficient quake resistance
A survey conducted in 1999 confirmed that the passing water capacity has lowered from 50 m3/s to The existing Musashi Canal was completed in 1967 but recent seismic design in about 37 m3/s since the time of the construction. preparation for a major earthquake has not been incorporated. Under the Musashi Canal Reconstruction Project, the canal will be reconstructed so that it will withstand the possible largest earthquake ground motions (Level 2 earthquake ground motions) in the future, and that the flowing and inner drainage capacities of the canal will be secured Crown height in 1967 even when a large earthquake occurs. (at the time of the completion of the construction) Araki Siphon Crown height in 2003
Tone River Tone Kamihoshikawa Siphon [Factors for lowered passing water capacity] [Factors[Factors forfor lowered paspassinsingg water capacity]capacity] Musashi Hakuchoda Siphon •• Reduced Reduced flow fflowlowareas, areas, and and uneven uneven longitudinal lonlongitudinalgitudinal grades ggradesrades due due tottoo uneven unevenuneven settlement settlementsettlement Asahi Shimbun, March 31, 2012 Canal Nagano Siphon •• Incapability IncapabilityIncapability in in passing passinpassingg waterwater duedue to to localized localized deformation dedeformationformation •• Dilapidated Dilapidated concrete concrete lining lininglining surface surfacesurface Yomiuri Shimbun, March 31, 2012 Musashi Canal Sama Water Gate Motoarakawa Siphon Kawazura Water Gate
Mida Siphon Nagano district Sta.: 44 + 00 Nukata Sluiceway Sinkage: 28.7 cm Ara River
Nukata district Sta.: 132 + 50 Seismic intensity Sinkage: 76.4 cm 3 or less 4 5 lower 5 upper 6 lower 6 upper 7 Road condition near Tsutsumine, Gyoda City (STA90) Case 1: Seismic intensity of the Tokyo-wan Hokubu Earthquake with shallow plate borders incorporated 5 6 The predicted distribution of seismic intensity of an inland earthquake that may occur in the future was released by a research team with the Ministry of Education, Culture, Sports, Science and Technology, 5 and the Earthquake Research Institute, University of Tokyo on March 30, 2012. 6
Current Musashi Canal (flood damage to the area near the water channel) Objectives of the Musashi Canal Reconstruction Project
1. Restoration of the function of steady flow There is an urgent need to reinforce flood control in the area around the Musashi Canal. To restore facility functions that have been declining due to dilapidation. To secure quake resistance and minimize damage caused by earthquake. In June 1966 immediately after the temporary start of the Musashi Canal with running { City water: Under normal conditions, the water is taken from the Tone Tap water of Tokyo: 30.274 m3/s Weir to the Musashi Canal so that up to about 35 m3/s of Industrial water of Tokyo: 0.980 m3/s water, 4,044 buildings were inundated above or below floor level by Typhoon No. 4. Tap water of Saitama Pref.: 2.700 m3/s water is conveyed to the Ara River. Industrial water of Saitama Pref.: 1.100 m3/s Total: 35.054 m3/s 2. Securement and reinforcement of the function of flood control Since April 1971, the water has been conveyed from the Oshi River and the Motoara River to the Musashi Canal 70 times, and a total of more than 1,000 buildings were To secure and reinforce the function of drainage, and reduce flood damage to the area near the canal. inundated above or below floor level in a total of 38 times from 1971 to 2010. {Inner drainage: A total of up to 60 m3/s of flood water from the Hoshi River, Yadoori River, Oshi River, and Motoara River is drained to the Ara River (50 m3/s of flood water is handled by facilities in consideration of time difference in the peak of flooding) . There is a need to increase flowing and drainage capacities. Tone Weir Musashi Canal Nukata Sluiceway (See the note below.)
Nukata
Drainage Pumping Ara River
ToneRiver Station Diversion works Diversion Oshi Riverbasin Hoshi Hoshi River basin (Note) Because of a time lag in reaching the peak flow Yadoori Riverbasin Motoara Riverbasin in the Hoshi River basin and the Yadoori River basin, the quantity of flow in the section reaches 3. Improvement of the quality of the water of the Ara River System to the maximum of 15 m3/s.
To convey the water for purification from the Tone River in order to contribute to improvement of the 7 quality of the water of the Ara River System. 8 { Water for purification: To contribute to improvement of the quality of the water of the Ara River System, up Typhoon No. 17 in Sep. 1996 (Nagano, Gyoda City) Torrential rain in Aug. 2004 (industrial park in Gyoda City) 3 7 to about 8 m /s of water is conveyed to the Ara River. 8 Typical cross section through the water channel after reconstruction Construction procedure with a half of the river closed
Amount of water conveyed temporarily: 21.6 m3/s Typical cross section CL
Second temporary water conveyance Reconstructed with a dual First temporary water water channel made of a conveyance reinforced concrete flume Water channel with concrete lining (150 mm in thickness)
Second temporary Completion of the first phase of water conveyance the construction of a water channel Quantity of flow Water channel Planned water Water channel Flow speed Photo: Second phase of the Section ̈́m3/sͅ grade depth (m) width (m) ̈́m/sͅ construction of the Aichi Irrigation System Upstream section 43.2 1/3,000 2.5 5.8 x 2 1.492
Midstream section 43.2 1/2,800 2.5 5.65 x 2 1.532
Downstream section 50.0 1/3,000 2.3 7.1 x 2 1.533 Third temporary water conveyance Administrative road Fence Fence
Administrative Third temporary road water conveyance Prefectural road
Completion of the first phase of the construction of a water channel Photo: Second phase of the construction of 9 the Aichi Irrigation System10
9 10 Overall project schedule Efforts to draw up an improvement plan with residents’ participation
Upstream Downstream section Midstream section section [Zone 1] [Zone 2] [Zone 3] [Zone 4] [Zone 5] C h e ic ne n h Li Gyoda City area Konosu City area ib i u en Li k Ara River R Konosu City sa (3,487 households with 18 neighborhood community (3,988 households with 20 neighborhood community a Gyoda City i ans lw k associations in 6 districts along the canal) associations in 4 districts along the canal) in aka Tone River a h Kawatsura T y S Water Gate
Hoshikawa Musashi Canal u JR Water Gate ts Nukata Drainage oe J Pumping Station Tone Weir Mida district
Outlet Outlet Yoshimi Town
Outlet Construction work Ota district
No. 8 Outlet Tamamiya district
River commissioned to JR Araki district Suka district Akamidai district Motoara River Hoshi Hoshi Nagano-otoshi Pumping Station Diversion works Diversion Nowata Drainage Shimooshi district Oshi Tsutsumine Outlet Sama Water gate
River Sama district Nagano district Old OshiOld Outlet River Fukiage district Overall project schedule for Main construction Temporary work, reconstruction of the Musashi Canal work, etc. subsidiary work, etc. About 7,500 households with 38 neighborhood community associations in 10 districts along the canal Fiscal 2010 Fiscal 2011 Fiscal 2012 Fiscal 2013 Fiscal 2014 Fiscal 2015 Working group 1 Working group 2 Working group 3 Working group 4 Working group 5 Upstream
Midstream and Provision of sidewalks Improvement of drainage
Open channelOpen downstream
Musashi Canal Musashi Inflow facilities Safety measures Reconstruction of Reconstruction
Reconstruction of Nukata Replacement of bridges Drainage Pumping Station
Administrative facilities Planting along the canal Coordination with planted roads
* The main work of the water channel is conducted during the period of limited water conveyance from Conservation of cherry blossom Conservation of December to May in the following year. Placement of sheet steel piles is scheduled in around October. 11 Major requests, etc. cherry blossom12 trees trees along the roads along the roads 11 12 Efforts to draw up an improvement plan with residents’ participation Reconstruction work (construction season in fiscal 2011) In the Musashi Canal Reconstruction Project, a conference with the participation of residents was organized to facilitate consensus-building among local residents with varied opinions with regard to the provision of safety facilities and landscaped facilities along the reconstructed Musashi Canal. All the relevant parties including neighborhood community associations and government offices have been working together so that the Musashi Canal will become attractive.
Difference of about 30 cm between the top of sheet piles, Construction work with excavated surfaces being protected and the water surface
Activity of the working group 13 14 Construction work in the area with rapid water flows (flow Construction with a large number of workers 13 rate of about 2 to 3 m/s) (maximum number of workers per construction area: about 100)14
Reconstruction work (construction season in fiscal 2012) Reconstruction work (construction season in fiscal 2012)
Construction work in a residential area (permanent Concrete placement by a concrete pump provision of acoustic barriers) Construction of the administrative road Water passing along both sides of the banks
15 16 Water passing along both sides of the banks (under the Construction work for oil protection above the water Construction work in a residential area (provision of a Water passing along both sides of the banks school road) 15 bridge) 16
About XRAIN (X-band MP Radar Information Network) Features of X-band MP radar Reference material 1. High resolution (characteristic of X-band) ○ Implement high-frequency, high-resolution X-band MP radar in urban areas for real-time rainfall observations to mitigate damage from localized heavy rains (known as guerrilla ・X-band radar operates on a shorter wavelength and allows for higher resolution imagery rains) and torrential rainfall. ○ Higher frequency (5x) and higher resolution (16x) than conventional radar (C-band than C-band. radar). Cut delivery time from 5-10 minutes to 1-2 minutes. (X-band: 8-12 GHz, C-band: 4-8 GHz)
[Conventional C-band radar] 2. Superior real-time capability (characteristic of MP radar) (Minimum size: 1-km grid cell, Data update interval: 5 minutes, Time to delivery: 5-10 minutes) ・Transmits two types of polarized waves (horizontal/vertical) to detect the shapes and [X-band MP radar] other properties of rain particles and estimate precipitation based on how flat, etc. the (Minimum size: 250-m grid cell, Data update interval: 1 minute, Time to delivery: 1-2 raindrops are. minutes) ・Able to send accurate rainfall data in real time without the need to calibrate with ground
rain gauge data Hanno City Okutama-cho Okutama-cho municipal government office 3. Capable of wind observation (Doppler radar function) Oume train line Oume City ・Measures rainfall velocity using Doppler effect for wind observations Hinode-cho
Hinode-cho municipal government office Hinohara-mura municipal government office Full view of X-band MP radar (Nomi Site) Hinohara-mura Metropolitan Inter-City Expressway Radar antenna (Saitama Site)
・High-frequency (5x) Vertically polarized waves ・High-resolution (16x)
Hanno City Horizontally polarized waves Okutama-cho Okutama-cho municipal government office Transmits 2 types of waves Oume train line
Oume City Hinode-cho Detects changes in the shape of raindrops Hinode-cho municipal government office Hinohara-mura municipal government office Radio waves transmitted Hinohara-mura Metropolitan Inter-City Expressway Radio waves received
* While the C-band radar (radius for quantitative precipitation estimation: 120 km) is suitable for wide-area rainfall observations, the X-band MP radar (radius for quantitative ZH: reflectivity factor、VD: Doppler velocity precipitation estimation: 60 km) is capable of gathering detailed data on localized heavy rain in real time despite its smaller area of coverage.
Advantage of Multiple Radar Observations XRAIN in Operation (Including stations to go on line in FY2013)
○ X-band MP radar sometimes misses precipitation echoes behind heavy rainfall due to [Legend] attenuation and dissipation of radio waves. These missed echoes can be picked up by using multiple radars. Currently in operation
Newly implemented Observation in Kanto Area (Rainfall on August 19, 2011)
To be put into operation in FY2013 Rainfall detection via radar in the Kanto area alone *Each circle indicates a radar range of 60 km in radius for quantitative observation. Heavy precipitation Kita-hiroshima
Shin-yokohama Wakuya Iwanuma Unable to detect Date Tamura Ujiie Radar station Yattajima Funabashi The Shin-yokohama Radar Station could not detect anything behind the area of heavy precipitation. Ichinoseki Ichihasama Kyogase Rainfall detection via combined use of Kanto and Shizuoka radar stations Nakanokuchi Mizuhashi Shin-yokohama Nomi Mt. Jubu Mt. Kanuki Taguchi Kanto
Fujinomiya Able to detect rainfall via radar in neighboring Shizuoka area Shinyokohama Mt. Kanuki Radar station Shizuoka Kita Bisai Anjo Multiple radar observation caught previously missed area. Suzuka Rokko Katsuragi Kumayama Tsuneyama Mt. Ushio Nogahara Mt. Kazashi Mt. Furutsuki Sugadake Kusenbu Sakurajima Ministry of Land, Infrastructure, Photos of XRAIN (X-band MP Radar) Ministry of Land, Infrastructure, Installation of XRAIN (X-band MP Radar) Transport and Tourism Transport and Tourism Kanto Regional Development Bureau [Kanto (Saitama) HQ] Kanto Regional Development Bureau ○ Recent years have seen increasing localized heavy rains and torrential rainfall, requiring enhanced rainfall monitoring. ○ High-frequency X-band MP radars that provide high-resolution rainfall measurements were installed in FY2009 (2 in Kanto area). ＸＲＡＩＮ -> Use radar network to facilitate optimal river and disaster management with an eye to minimizing damage
Installation of X-band MP Radars C-band and X-band Radar Rainfall Image
Location of XRAIN in Kanto Area Kanto (Saitama)/Shinyokohama [Existing (C-band) Radar] [X-band MP Radar] Minimum size: 1-km grid cell, Minimum size: 250-m grid cell, Data update interval: 5 minute, Data update interval: 1 minute, Time to delivery: 5-10 minutes Time to delivery: 1-2 minutes Building 2 Building 1 Can capture more Area specific areas of blocked by steel tower heavy rain Kanto Regional Development Bureau Kanto (Saitama) HQ Keihin River Office Shinyokohama X-band MP Radar Rainfall Data - Test Operations Branch
2 units installed in Shinyokohama and Saitama New Urban Center Radar range with 60 km radius for quantitative observation (blue circles)
・ Higher frequency (5x) and higher resolution (16x) than conventional (C-band) radar. Cut delivery time from 5-10 minutes to 1-2 minutes. ・ While the C-band radar (quantitative precipitation estimation radius: 120 km) is suitable for wide-area rainfall observation, the X-band MP radar (quantitative precipitation estimation radius: 60 km) is capable of gathering detailed data on localized heavy rain in real time despite its smaller area of coverage. XRAIN: X-band polarimetric (multi parameter) RAdar Information Network XRAIN Rainfall Data Data Synthesis Office Radar
Ministry of Land, Infrastructure, Transport and Tourism NHK Digital Terrestrial Broadcasting Service Kanto Regional Development Bureau
■ Background ○ Recent increase in torrential rainfall (guerrilla rain) hazards have been a major concern (River water level rises rapidly) -> (Need to get evacuation info., etc. out ASAP) ○ Disaster information for rivers, etc. (water levels, rainfall) is provided via the integrated river information system. (Conventionally via PC, mobile phones, telephone information service, etc.) ○ TV, used by people of all ages, is the most appropriate means of conveying disaster information.
Information on river water levels and rainfall is provided by NHK via its digital terrestrial broadcasting service.
[River Water Levels] River Water Levels River water levels and rainfall River conditions at gauging station TVTV screenscreen The water level beyond which any increase will cause Bankfull stage flooding Evacuation stage The water level at which evacuation site information is TV announced The water level at which people are urged to watch for Warning stage flood information Flood response The water level at which flood fighting teams prepare to alert stage take action screen River Gaging station Municipality Status
[Rainfall] Rainfall
July 2011 Digital terrestrial broadcasting launched Hourly rainfall in Saitama Prefecture April 2012 River water level and rainfall information TV screen service launched via NHK‘s digital terrestrial broadcasting
Press this button to switch between rainfall and water level information
Overview of the Arakawa River Basin
Area: 2,940 km2 Low-lying land Mountains About the Site Plateaus Trunk length: 173 km Hills Basins Basin population: 9.3 million
Population density: 3,160 people/km2
Population of flood-prone areas: 5.4 million
Assets within flood-prone areas: 78 trillion yen
Kobushigata ke (El. 2475 m)
Prefectural area: 3,797 km2
Topographical classification Percentage of river basin to the total area of river basin of Saitama Prefecture (3,797 km2)
December 14, 2012 Tonegawa River Arakawa River basin basin (1,357 km2) (2,440 km2) 36% 64%
Rerouting of the Arakawa River Eastward rerouting of the Tonegawa Rerouting of the Arakawa River and westward rerouting of the Arakawa Late 12th Century - Early 17th Century Watarasegawa River Kinugawa River Kokaigawa River ○ Araburu (Stormy) River The course of the river below the alluvial fan (near Kumagaya City) frequently changed.
○ Ina Tadatsugu's rerouting project (1629) (Motoarakawa -> Wadayoshinogawa) Rerouting of Ca. 1630 Known as the westward rerouting of the the Arakawa Arakawa River, the project set the current River Pacific course of the river. Tonegawa River Ocean Bizentei ○ New inundation-prone area (embankment) Before eastward rerouting of the Tonegawa River Edogawa River -> Right bank of the Arakawa River Surrounding embankments ○ Omiya After eastward rerouting of the Tonegawa River
Before westward rerouting of the Arakawa River Tokyo Bay ○ Large embankments constructed around After westward rerouting of the Arakawa River the fiefdoms of Yoshimi and Kawashima by the Edo government Rerouting of the Arakawa River Rerouting of the Arakawa River
Started in 1911, completed in 1930 Early 17th Century - Late 19th Century Surrounding embankments River Improvements during the Modern Era (Late 19th Century - Late 20th Century) Downstream Improvements by the ○ Nihon-zutsumi (1693) National Government A funnel-shaped embankment was ○ Factories were built along the Sumida constructed along with the Sumida- River during the early 1900s. They Iwabuchi zutsumi (Sumida embankment), designed suffered major damage due to frequent to flood the river upstream to protect flooding. Edo. Trenching of a ○ After the toll from the devastating 1910 diversion channel flood, the Japanese government ● Docks implemented a national project ○ Riverside development Iwabuchi Channel dubbed the Arakawa River excavation route With the growth of river Improvement Plan. transportation businesses, river docks ○ Arakawa Diversion Channel (1911 - 1930) Nihon-zutsumi and Course of the were built to serve as Sumida-zutsumi ・ Area of land purchased: approx. 1,089 ha Sumidagawa River transport hubs for were constructed to (Former course of the Arakawa River) goods and materials. flood the river ・ Number of houses relocated: 1,300 upstream from Edo.
Location of docks along the Arakawa and Shinkashigawa Rivers (ca. 1700)
Characteristics of Rerouting of the Arakawa River the Arakawa River
Midstream Improvements by the Started in 1918, completed in 1954 National Government A low-water channel was straightened / levees and cross ○ Midstream improvements (1918 - 1954) levees were constructed. ・Ensured the river's original function as a flood control basin Kawashima ・Straightened meandering course of the river Jisui Bridge ・Constructed levees New levees were constructed using the existing levees (surrounding embankments, etc.). ◎ Widest in Japan ◎ About 60% of the high- ◎ Cross levees for flood The project made the middle course of the river 1.5 km to (2.5 km) water channel is private land retarding Main levee 2.5 km wide. Cross levee ・Constructed 26 cross levees to enhance flood retarding State-owned官有地 Private land 38% effect. 民有地 New levee 62% after ・Reducing flood discharge downstream (Tokyo) / improvement constructing flood control reservoirs and levees Direction of flow midstream were required in later river improvement River width Main Direction of flow projects. levee 2.5 km Main levee
Cross ○ Improvement at the confluence of the Irumagawa and levee Cross Old river Athletic運動場 Arakawa Rivers Under normal conditions levee Parks,公園 field Golfゴル courseフ場 Current 10% Under normal conditions (1931 - 1942) Jisui Photo taken in August 1999 near そのetc.他 3% ・ 4.5-km separation levee Bridge Kawashima-cho 16% Photo taken in August 1999 near Kawashima-cho ○ Work on 3 diversion rivers (1931 - 1954) ・Separation of the Oppegawa, Koazegawa, and River channel before Main Irumagawa Rivers Direction of flow Main improvement levee Agricultural land Direction of flow 農耕地 levee Straightening low-water Cross 71% Cross channel midstream levee levee
During flooding During flooding Past Major Floods September 7, 2007 Typhoon Fitow
Flooding near Onari Bridge in Yoshimi-cho (61.4 k)
Nukata Nukata Bridge Bridge Flood of 1910 Typhoon Kathleen (1947)
Flooding near Jisui Bridge in Saitama City (42.0 k)
Kawago Kawago e City e City Jisui Bridge ◎ 568 mm in Mitsumine, 611 mm in Chichibu ◎ 24% of Saitama Prefecture was inundated. ◎ The levee broke in Kugejisaki, Kumagaya. The muddy ◎ Tokyo was flooded for two weeks. overflow from the Arakawa reached Tokyo Bay. Jisui Bridge 堤防決壊Levee breach １７８箇所178 locations 堤防決壊Levee breach ２箇所2 locations 死傷者Casualties ３２４名324 死傷者Casualties １６名16 84,538 units Housing damage 住宅被害Housing damage ８４，５３８戸 住宅被害 ２８，28,520５２０戸 units Under normal conditions During flooding
Arakawa River Flood Control Reservoir No. 1 Reservoir Facilities Aerial photo of A sectionthe of reservoir the high-water channel is surrounded by a levee that serves as a flood control reservoir. This enhances flood retarding Water level Intake control weir effect and mitigates flood damage downstream. Showa levee Water purification Floodgate facility Akigase Intake
City Asaka Flooding in April 1999 Saitama City
Tokyo Outer Toda Ring Lake City Road Saiko
View from downstream Stormwater flowing into Lake Saiko via an intake levee located at the lake's upstream section. Functions and Roles If the August 1999 flood ・Controls floodwater and mitigates flood damage occurred today, the reservoir ・Ensures drinking water supply for the Tokyo metropolitan would store approximately Flood Control Reservoir area 3 No. 1 drainage gate ・Protects natural environment and serves as a venue for 20,000,000 m of stormwater Intake levee outdoor activities and reduce the peak Lake Saiko discharge at the downstream (Arakawa Reservoir) Total area 5.8 km2 control point (Sasame Pumping Bridge) to about 560 m3/s, station Length 8,100 m Water intake/distribution Containm Flood control pipe 3 lowering the water level by Sakuraso ent levee Flood control capacity 39,000,000 m facilities Discharge Floodgate pipe Water supply capacity (Lake 30 cm. 10,200,000 m3 Water supply Saiko) facilities Arakawa-Joryu River Management Office, MLIT 1. Overview of Arakawa River Flood Control Reservoir No. 1 2. Flood Control Function
Cross section Flood control reservoir Arakawa River
Asaka City High water level under ■ Overview (1) During the early
Saitama City Design flood level flooding conditions: A.P. stages of flooding +11.925 m Approx. 39,000,000 m3 Flood Control River channel Reservoir No. 1 Arakawa River High water level during ・The Arakawa River Flood Control Reservoir Flood Control non-flooding period: A.P. Reservoir No. 1 +3.9m No. 1 is designed to control flooding of the Tokyo Outer Ring Road High water level during flooding period: Overflow levee A.P. +1.65m Arakawa River in stages. AP +8.700 m Wako City (Sakitama Ohashi Bridge) Approx. 10,600,000 m3 ・The overflow levee is designed for an influx of Lake Saiko Reservoir bottom elevation: A.P.-6.3 m floodwater once every ten years. Once the water level of the river exceeds A.P. +8.700m, Flood control ■ Controls 850 m3/s beyond design flood level flood control is initiated. Under normal Flood control during the ・When the reservoir is used for flood control, all conditions August 1999 flood (2) During flood peak of its floodgates are fully closed so that they serve as a containment levee.
[Flood control reservoir] Sakuraso Floodgate Drainage gate AP +8.700 m Area: Approx. 5.8 km2 Flood control capacity: Approx. 39,000,000 m3 Year completed: 2004 [Reservoir (Lake Saiko)] Storage capacity: 11,100,000 m3 Depth: 8.5 m (flooding period), 10.7 m (non- flooding period) To Asaka Water Purification Plant Year completed: 1997 Water supply ■ The reservoir (Lake Saiko) with a Akigase Intake water supply capacity of 10,600,000 Weir m3 and purification facility make it ■ Overflow levee specifications possible to supply up to 300,000 m3/day of drinking water to the Crown height Length Flood Control River channel Tokyo metro area. Reservoir No. 1 Before AP +8.700 m 320m Environment 57,000 12,000 7,000 6,000 7,000 6,000 7,000 12,000 construction ■ Lake Overflow Popular spot for recreation, Saiko environmental learning activities, etc. levee ▽A.P.+14.425m 2 1 Containment囲尭堤 levee 1: :2 Overflow 1:10 1:10 ▽A.P.+8.700m levee :3 １ 1: 1 ： ８ ： ８ 3 1:10 １ ▽A.P.+6.292m ▽AP+5.000
29,600 5,000 19,264 DL=0.00 DL=0.00
53,864 Wild primrose field Arakawa River Flood Control Before the project (mid 1970s - mid 1980s) Lake Saiko Biotope (Tajimagahara) Reservoir No. 1
3. Effect of Arakawa River Flood Control Reservoir No. 1 4. Arakawa Reservoir (Lake Saiko)
■ Objectives of the Arakawa River Comprehensive Flood Control Reservoir Development Cross-sectional diagram 調節池 Project 荒川 ■Flooding caused by August 1999 tropical storm 洪水時満水位A.P.+11.925m ■Effect against August 1999 flood ● Flood control Build Arakawa River Flood Control Reservoir No. 1 to control a flow of 850 m3/s. beyond 越流堤A.P.+8.7m Although the reservoir was still under construction, If the August 1999 flood occurred today, the reservoir would store design flood level. 3 floodwater poured into the reservoir from 10:00 p.m. on approximately 20,000,000 m of stormwater and reduce the peak discharge at ● Drinking water supply 非洪水期満水位A.P.+3.900m AP.+3.73～3.85m 3 3 洪水期満水位 秋ヶ瀬堰管理水位 August 14 to 10:00 a.m. on August 15 (approx. 12 hours). the downstream control point (Sasame Bridge) to about 560 m /s, lowering the The Arakawa Reservoir, with an active capacity of 10,600,000 m , and the river purification A.P+1.650m water level by about 30 cm. facility are used to supply 2.1 m3/s (max. 181,400m3/day) of drinking water to Saitama R Prefecture and 1.4 m3/s (max. 121,000 m3/day) of drinking water to Tokyo. 最低水位A.P.-6.300m e Flood Simulation Results (Comparison of Inflow Volumes at Sasame Bridge) s 平成11年8月洪水 ■ Years implemented e Flooding period (July 1 - September 30) Arakawa Non-flooding period (October 1 - June30) r River 6000 1980 - 1996 荒一建設前 Flood control effect v 5500
流量（m (1) Siphon off water from the Arakawa Reservoir (Lake Saiko) and deliver it upstream from the Total storage capacity: 11,100,000 m . 2500 3 2000 Akigase Intake Weir to secure a supply of drinking water Active capacity: 10,600,000 m 1 1500 (2) Use treated wastewater that has been purified by the river purification facility for the Location: Toda City, Saitama City, Wako City 1000 maintenance flow downstream from the Akigase Intake Weir to secure a supply of drinking
500 Floodwater inflow water 平成22年9月6日現在 0 【水道用水の補給】 【維持用水の振り替え】 8/14 0:00 8/14 12:00 8/15 0:00 8/15 12:00 8/16 0:00 8/16 12:00 8/17 0:00 ①②荒川貯水池の補給実績 浄化施設の振り替え実績 日時 年 総補給量 補給 補給時間 総補給量 補給 振り替え ■Flooding caused by September 2007 Typhoon Fitow (千m3) 日数 (千m3) 日数 運転時間 平成７年度 6,369.0 36 488 11,411.6 131 3,158 Floodwater poured into the reservoir via the overflow levee from 3:45 Flood Simulation Results (Comparison of Water Levels at Sasame Bridge) Drinking water supply (population/areas served) p.m. to 6:40 p.m. on September 7 (approx. 3 hours). The reservoir held 平成８年度 3,037.0 11 144 4,854.8 102 2,378 [Saitama Prefecture] 平成９年度 － － － 28,664.7 178 4,137 approximately 30,000 m3 of floodwater. ・Population: Approx. 3.8 million 平成10年度 － － － 12,870.1 84 1,952 ・Areas (Okubo Water Purification Plant) Arakawa 平成11年度 － － － 7,461.0 42 951 16 cities and 1 town in south central and western River Flood 平成12年度 －－ － －－ － areas of the prefecture, including Saitama City Control 平成13年度 － － － 11,126.8 52 1,185 Floodwater overflowing Reservoir (excluding Iwatsuki Ward), Kawagoe City, Kawaguchi 平成14年度 －－ － －－ － into the reservoir No. 1 Overflow City, etc. 平成15年度 － － － 453.6 3 42 levee 平成16年度 － － － 4,136.4 18 383 [Tokyo] Arak 平成17年度 －－ － －－ － Hanekura ・Population: Approx. 11.2 million Rese awa 平成18年度 －－ － －－ － River Bridge Reduced water level ・Areas (Asaka Water Purification Plant) rvoir 平成19年度 65.0 28 678 － － － No. 1 by approx. 30 cm at A portion of 16 wards, including Chuo, Bunkyo, ↑ 平成20年度 － － － 1,731.6 18 289 Sasame Bridge. Chiyoda, Kita, Itabashi and Toshima Wards, and 平成21年度 3,709.0 26 453 － － － Arakawa River some areas of Tama and Machida Cities. 平成22年度 428.0 3 50 － － － 計 13,608.0 104 1,813 82,710.6 628 14,475 Flow of the Arakawa River and Major Facilities Tone-Ozeki Weir Role of Lake Saiko (Supplying Water to Tokyo Flow of the Arakawa River and Major Facilities and Saitama)
Tonegawa River Intake of agricultural water (3) Okubo Water (2) Discharged Purification Plant Drinking and industrial water Akigase Weir water area supply for Saitama Rokuzeki Headworks Prefecture (3) Asaka Water Purification Plant Tap water used in Saitama Kumagaya City Prefecture Kakkaku Dam (Saitama City, Toda City, Minumadai Canal Kawagoe City, Shiki City, etc.) (Saitama Prefecture) Musashi Canal (2) Discharged Uematsu Bridge Arakawa Reservoir (Lake Okubo Water Saiko) Tap water used in Tokyo Dried-up section Purification Plant (Tokyo's western wards, etc.) Yoshidagawa River (Ministry of Land, (Saitama Prefecture) Takizawa Dam Infrastructure, Transport and (Japan Water Agency) Tourism) (1) Akigase Intake Weir (To be completed in Flow improvement Saitama City FY2009) Yorii channel and low- gradient fishway Purification Water supply canal Otaki-mura facility Nakatsugawa River connecting to the Chichibu City Oashi Bridge (6) Water pipe Arakawa River JR Musashino Line Lake Saiko Dried-up section Arakawa-mura Arakawa River Futase Dam Sugama (Ministry of Land, Urayamagawa River Arakawa River (5) Pumps Infrastructure, Transport Kawagoe City Shingashigawa River Akigase Intake Weir and Tourism) (Japan Water Agency) Naguri-mura Irumagawa River (4) Lake Saiko Arakawa Joryu River (Arakawa Reservoir) Urayama Dam Office, Ministry of Sumidagawa River (Japan Water Land, Infrastructure, Asaka Water Agency) Transport and Tourism Purification Plant ◆ Water is <2. discharged> upstream from the <1. Akigase Intake Weir> on the Arakawa (Tokyo) Arima Dam River and purified at the <3. water purification plants> to produce drinking water, etc. to be (Saitama Prefecture) supplied to Tokyo and Saitama Prefecture. ◆ When the river's water level recedes, water is discharged from upstream dams or water Tokyo Bay Drinking and industrial water is <5. pumped> from <4. Lake Saiko> and discharged into the river upstream from the supply for Tokyo Akigase Intake Weir via the <6. water pipe> to secure drinking water, etc.
Using the Arakawa's Urban Water Water Supply ● Increasing use as drinking and industrial water ● River water has long been used for agriculture and hydropower generation. ● Water from the Tonegawa River is conveyed via the Musashi Canal and taken at the Akigase Intake Weir. ● Today it is increasingly used for urban drinking and industrial water. ● Supplying drinking water to approx. 15 million people ● Approx. 80% of the urban water supply comes from the Tonegawa River. Supplying drinking water to approx. 15 million people (11.2 million in Tokyo and 3.8 million in Saitama)
* The above figure for Tokyo is the number of people living in the area Water Rights to the Arakawa River Water Rights to Japan's Class A Rivers where water can be supplied. The actual number is roughly 5 million.) (including Water Taken from Tonegawa (Source: River Handbook 2004) River)
Agricultural Other water Agricultural water Musashi Canal
Water for power generation
Water for Drinking power water generation Drinking water
Industrial Industrial water water Akigase Intake Weir 5. Environmental Measures and Uses after Completion Lake Saiko, an urban oasis visited by 1.7 million people ●The Tajimagahara Wild Primrose Field, which is designated as a "special natural monument" by the Japanese government, is located within the flood control reservoir. annually ● To ensure that the construction of the containment levee does not have any adverse effect on the water environment of the wild primrose habitat, environmental conservation measures are implemented in cooperation with the Agency for Cultural Affairs, Saitama Prefectural Government, etc., including developing rules for operating the Sakuraso Floodgate. ● The number of primrose plants has doubled since the beginning of reservoir construction. ● Built within the Arakawa River Flood Control Reservoir No. 1, Lake Saiko, Doman Green Park, Akigase Park, etc., attract about 1.7 million visitors annually (estimate for 2006).
■ Sakuraso Floodgate protecting the environment ■ Uses of Arakawa River Flood Control Reservoir No. 1 The Sakuraso Floodgate is designed to discharge water from the Kamogawa River into the Arakawa River. Fully closed during flooding, その他各種施設利用野外活動陸上スポーツ散策・休憩等 it serves as a containment levee. Floodgate operation rules have been developed in light of the flooding 散策・休憩等 frequency of the wild primrose field. 1,800,000 Sakuraso Floodgate 1,600,000 1,400,000 1,200,000 散策・休憩等 陸上スポーツ
1,000,000（人 ） 散策・休憩等 Showa 散策・休憩等 800,000 陸上スポーツ 陸上スポーツ Floodgate 600,000 野外活動 野外活動陸上スポーツ 野外活動 Tajimagahara Wild Primrose Field Lakeside teeming with hikers Kamogawa River 400,000 野外活動 200,000 各種施設利用 各種施設利用 Arakawa River 各種施設利用 各種施設利用 0 H11 H12 H13 H18
1% 1% 湖面利用 Lake Saiko 1% 2% 湖畔利用
98% 99% 99% 99%
Discharge gate Tajimagahara Wild Primrose Field (Source: Arakawa River Reservoir Monitoring Study Report, National Census on River Environment: 6000 １９６５年～２００８年サクラソウ平 均生育個体数経年変化 Waterfront Space Use Survey) Uses Examples of uses 5000 Outdoor activities 平均生育個体数 さくらそう水門完成 Hiking, resting, etc. Walking, resting, etc. 4000 彩湖運用開始
数 Doubled 3000 Track and field sports Jogging, cycling, etc.
2000 第一調節池事業完 平均生育個体 Outdoor activities 成 BBQ, nature observation, etc. 1000 第一調節池事業着手 Use of facilities 0 Learning center, etc.
Primrose H1 H3 H5 H7 H9 S40 S42 S44 S46 S48 S50 S52 S54 S56 S58 S60 S62 H11 H13 H15 H17 H19 People enjoying wind surfing on the lake Toda Marathon at Lake Saiko 測定年 (Source: Report on Impact of Arakawa River Reservoir Construction on Tajimagahara Wild Primrose Field (2008))
Lake Saiko Nature Center
First floor exhibit room Underwater Wonders Fourth floor exhibit room Forest Wonders 10 aquarium tanks of various sizes reflect the water environment and inhabitants of the Here enlarged models give nearby Arakawa River as well as its related visitors an up-close look at the ponds and tributaries. forest ecosystem as they learn about the woods surrounding Lake Saiko and the woodland homesteads that dot the area.
Fifth floor exhibit room Second floor exhibit room Arakawa River Environment Waterfront Wonders and People
A diorama of waterfront plants and This exhibit looks at the history of other displays illustrate the flood control along the Arakawa and waterfront environment and its use of its waters as well as how the inhabitants. The Waterfront river has shaped cultures and Theater is a video showcase lifestyles over the ages. There is a introducing visitors to Lake Saiko's large diorama showing the important role Lake Saiko plays as well as a seasonal changes and ecological video (Arakawa Theater) all about food chain. flood control and water uses.
Third floor exhibit room Grassland and Marshland Wonders Orientation Room The exhibit introduces visitors to various Here computers are used to brief plants and animals living along the river groups of visitors, students, and bank including the grasslands and others on the highlights of the levees that are their habitats. The field facility. observation station provides tips for doing field work around Lake Saiko as well as information and materials that aid environmental education. 1. Edogawa, a Sea Level City ・Geographic Features ・The Fight against Floods (History) 2. Structural Measures ・Super Levee Construction Integrated into Community Development 3. Nonstructural Measures ・ Thailand's Chao Phraya River Creating and Distributing Flood Hazard Maps ・ Basin Flood Control Project Evacuation Advisory Standards ・ Counterpart Training Evacuation Guidance for Residents ・Challenges and Tasks Ahead (Wide-area December 17, 2012 Evacuation) Edogawa City 1 ・Information Gathering and Delivery Tools 2
Typhoon Kathleen (1947) Aerial photo
・Area: approx. 49 km2 (8 km east to west, 13 km north to south) 1947 Typhoon Kathleen Shinkoiwa - Koiwa Station, Edogawa City People fleeing ・Population: approx. 680,000 3 4 Seawall Destroyed by Typhoon Kitty (1949) South Exit of Hirai Station after Typhoon Kitty (1949) Typhoon Kitty
5 6
Typhoon Kitty Inundation Map (1949) Ground Subsidence due to Pumping of Groundwater
Showa Meiji Taisho Showa Heisei Showa 40 23 4 15 2 0 Cumulative subsidence(m)
1 Senju Shinmachi, Adachi City
2 Nakakatsushika, Edogawa City Sank 2.4 m
3 Tachibana, Sumida City Benchmark Cumulative Year measuring Benchmark location Exposed well casing number subsidence (m) begun Minamisuna 2-chome, Koto City 5th Construction Office, Kameido 7-chome, Koto City 1918 1892 Kameido, Tachibana 6-chome, Sumida City Tokyo Metropolitan 4 1935 Nakakasai 3-chome, Edogawa City 1918 Koto City Government Senju Shinmachi, Adachi City 1892 (Shinkoiwa 1-chome, Shimizucho, Itabashi City 1932 Shimokiyoto 2-chome, Kiyose City 1972 Katsushika City) Sumiyoshi-cho 3-chome, Hoya City 1971 Minamisuna, 7 5 Koto City 8 1890 1915 1940 1965 1990 Ground Height of Low‐lying Impact of Subsidence (Main Entrance of Edogawa City Office) GroundLand Height in Eastern of Tokyo Low-lying Land in Eastern Tokyo
Below mean low water (AP 0 m)
Below mean high water (AP 2.1 m)
Below design high tide level (AP 9 5.1 m) 10
Nakagawa River (Matsushima District) ３０H
H
High tide level during spring tides
11 12 13 14
Creating and Distributing Flood Hazard Maps Evacuation Information Provided by Local Governments By law ・ The Flood Control Act requires municipal governments to create and distribute flood hazard maps. Creating/distributing flood hazard maps Flood hazard maps should include: Issuing evacuation advisories and orders 1. Flood zone and types of damage (extent, inundation depth) 2. Evacuation sites Evacuation sites, routes, etc. (names and locations of evacuation facilities) 3. Means of communicating evacuation information such as flood forecasts, etc. Means of conveying information to residents (channels and means for communicating evacuation advisories, etc.) 5. Where to get weather information, etc. (names, locations, URLs, etc. of river and rain gauging stations)
16 Indicating Water Levels (Komatsugawa Elementary School) Arakawa River Water Level Display Tower (in Front of Edogawa City Office)
キティ台風潮位（A.P.3.1
大潮の満潮位（A.P.2.1m）
大潮の干潮位（A.P.0m） 1717
Flood forecasts conducted soley by the Japan Meteorological Agency Issuing Evacuation Advisories and Orders Issuing Evacuation Advisories and Orders
How information is delivered to you (1) Types of evacuation instructions and criteria for issuing evacuation instructions
TV/radio/ Japan Meteorological
Agency's local Flood forecasts conducted Internet Edogawa City Evacuation preparation/action Types soley by the Japan meteorological Meteorological Agency observatory residents
People who can evacuate on their own Action (ambulatory) 危険度Risk Type 避難時の行動 Conditions Flood forecast level 種類 Ambulatory Non-ambulatory 発令時の状況 Flood forecasts jointly 一般 要援護者 conducted by the Ministry of A flood forecast will レベル Land, Infrastructure, Transport and Tourism and the Japan be announced when Meteorological Agency there is a possibility 高いHigh 決壊につながるような大量の漏水や亀裂There is a likelihood of a levee breach, due to a major of flooding. Complete Use it to decide Evacuation order leak, cracks, etc., posing a significant threat to public Sound truck/disaster management 避難指示 避難完了 の発生など、人的被害発生の危険性が非 radio communications whether or not you evacuation should evacuate. safety. Ministry of Land, People requiring assistance when 常に高いと判断されたとき Infrastructure, Transport evacuating (non-ambulatory)* and Tourism Complete 一般者（通常の避難行動が可能）が避難Flooding is imminent, posing a clear threat to public Evacuation Start evacuation safety. Everyone able to evacuate on their own 避難勧告Evacuation advisory 避難開始evacuating 避難完了 開始しなければならない段階で、人的被 Edogawa City instructions (those who are ambulatory) must start evacuating at The City will advise 害発生の可能性が明らかに高まった状態this stage. Disaster management you on what to do. Follow instructions Evacuation advisory for the Flooding is imminent, posing a clear threat to public headquarters Police and fire departments carefully. 要援護者（避難に時間を要する）が避難 要援護者避難勧告non-ambulatory Start safety. Anyone needing more time to evacuate (those Evacuation evacuating How to prepare to (Evacuation preparation for 避難準備 避難開始 開始しなければならない段階で、人的被who are non-ambulatory) must start evacuating at evacuate and what （一般避難準備）the ambulatory) preparation to keep in mind this stage. Tokyo Metropolitan when evacuating 害発生の可能性が高まった状態 Government (See pages 5 and 6) Flooding is likely to occur, posing a possible threat to Evacuation 要援護者が避難準備を開始しなければな Evacuation preparation public safety. Anyone who is non-ambulatory must *Those who need assistance during a disaster such as the elderly and 要援護者避難準備for the non-ambulatory 避難準備preparation らない段階で、人的被害発生の可能性が disabled See page 8 for more details. start preparing to evacuate at this stage. 低いLow ある状態
Issuer of advisories/orders As a general rule, the mayor issues evacuation advisories/orders (Article 60, Basic Act on Disaster Control Measures) 19 20 Issuing Evacuation Advisories and Orders Evacuation Sites, Routes, etc. (2) When to issue evacuation advisories/orders (1) Evacuation sites Before flooding has started, local disaster management bases are the River water level criteria for determining when to issue an evacuation evacuation sites of first recourse (①). Once flooding begins, nearby shelters advisory/order [For Reference] Water Levels and Forecast Points are the evacuation site of first recourse (②). Advisories and orders are issued in light of 水防団Flood はん濫 避難判断はん濫 response 水位標 河川名River Gauging 観測所 待機水位注意水位Warning 水位Evacuation 危険水位Bankfull Gauge zero Local disaster management bases name station alert stage stage (m) stage (m) stage (m) 零点高point river water levels (for the Arakawa, Edogawa (m)(m) (m) (m) (m) ・ ① Oshima Komatsugawa Park (design occupancy: 荒川Arakawa Iwabuchi 岩淵 Before flooding River 3.0 4.1 7.0 7.7AP.0.0m 197,000) and Nakagawa Rivers). begins Nishiseki ・ Kasai Nanbu area (design occupancy: 270,000) Edogawa yado西関宿 4.5 6.1 8.5 8.8YP.+8.5m River江戸川 ・ Konodai Danchi housing complex (design occupancy: ● River water levels for issuing flood forecasts Noda野田 4.6 6.3 8.9 9.2YP.+3.4m 200,000) Nakaga wa中川 River Yoshikawa 吉川 3.3 3.6 3.9 4.2AP.0.0m Risk level Design flood level Non-ambulatory Ambulatory Emergency shelters High ② After flooding *Note that floors where people Evacuation order Bankfull stage begins ・ 33 junior high schools can evacuate to are specified Evacuation advisory ・ 73 elementary schools at each facility. Evacuation stage Evacuation advisory Evacuation preparation
Levee Warning stage Evacuation ③ When there is Sturdy nearby building that is three or more Flood response alert stage preparation not enough time to stories high
Low get to an (When you have to act quickly in a life threatening Normal level emergency shelter situation) 21 22
Evacuation Sites, Routes, etc. Evacuation Sites, Routes, etc. (2) Where to go (3) Challenges Konodai Danchi ● When evacuating, people should flee in Since the elevation is below sea level, people may be cut off for a long the direction shown on the existing period of time if the area is flooded. hazard map. Local disaster management bases These are outdoor locations without roofs where evacuees will have to put up with inconveniences.
● Emergency shelters Oshima Since lower levels will be submerged, floors that Komatsugawa Park can accommodate evacuees are limited.
Sturdy nearby building that is three or Kasai Nanbu area ● more stories high Evacuees may be cut off for a long period of time. Oshima Komatsugawa Park (design occupancy: 197,000 people) 23 Evacuation Sites, Routes, etc. Means of Conveying Information to Residents (4) Future tasks Wide-area evacuation plan is needed to allow people to flee to high ground outside Edogawa City ASAP. Gathering Providing information information
River information system City's disaster MCA radio communication management radio communication system Edogawa City system Meteorological information Twitter collection system Edogawa e-mail news Disaster management FM Edogawa information system Emergency broadcasting ・Develop a criteria that will help people to quickly decide whether they Surveillance cameras system should evacuate or not ・Ensure safe evacuation facilities outside the city ・Develop long-distance evacuation guidance strategies ・Get guidance from officials who issue evacuation orders (national All communication tools are managed by the government, governor, etc.) when damage is extensive Disaster Management Headquarters
Means of Conveying Information to Residents Means of Conveying Information to Residents River information system MCA radio communication system (vehicle tracking system)
Gives access to river basin rainfall data, water level data and Displays location of vehicles equipped with MCA radio communication system. live camera images provided by River Offices in Kanto. Lets headquarters personnel track vehicles on screen and dispatch (Dedicated lines from River Offices) them where needed. Means of Conveying Information to Residents Means of Conveying Information to Residents Meteorological information collection system Disaster management information system
Disaster management November 29, 2012, 4:50 p.m. Disaster management headquarters November 29, 2012, 4:50 p.m. Disaster area organizations
Disaster management information system
Rainfall Edogawa City Komatsugawa Shinkawa Shin-Sakongawa Tokyo Office Branch Koiwa Branch Shishibone Branch Tobu Branch underground Kasai Branch River floodgate parking lot Koiwa Branch Metropolitan Government. Input data into the 10-minute rainfall Report disaster situations via Tokyo Metropolitan disaster management radio Government's DIS communications, mobile Cumulative rainfall Komatsugawa Branch Shishibone phones (e-mail, photos, etc.) Branch Wind speed
Average wind speed Edogawa City Office
Maximum wind speed Water level Wind direction at North- North- North- North- Tobu Branch North Northeast Northeast West northeast maximum wind speed northeast northwest northeast
Temperature Ask police/fire Shinkawa underground parking lot departments for Local atmospheric Assess situation, make assistance pressure decisions (instructions/orders) Inland water level Kasai Branch
River water level Shin-Sakongawa River floodgate Information from the disaster area (fires, building damage, Collects/displays data from rain gauges and anemometers installed etc.) is centrally managed to facilitate quick decisions at in 8 locations (mainly branch offices) throughout Edogawa City. It also collects water level data at the Shin-Sakongawa River disaster management headquarters and speed up emergency floodgate managed by Edogawa City. response operations.
Means of Conveying Information to Residents Means of Conveying Information to Residents
Surveillance cameras City's disaster management radio communication system
Tower Hall Funabori Edogawa City Office Disaster Management Cameras Headquarters
Controllers 272 units installed Media converter (covering the entire city) Can be controlled remotely from the disaster management headquarters Means of Conveying Information to Residents Means of Conveying Information to Residents
Twitter Edogawa e-mail news Edogawa City official website
City office
Residents have to seek out the information they Used by people of all ages and delivered want automatically
Means of Conveying Information to Residents 航空写真 FM Edogawa emergency broadcasting system Transmitting station Studio (Minamikoiwa) ・During the night when the studio is not staffed During ・When communication lines are damaged disaster Normal× broadcasting Ｔｈａｎｋ ｙｏｕ ｆｏｒ ｙｏｕｒ ｋｉｎｄ ａｔｔｅｎｔｉｏｎ
Disaster management headquarters Disaster management
Interrupter headquarters interrupts broadcast About the Arakawa River Contents
1. About the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) 2. About the Arakawa River
3. Diverting the Arakawa
4. Downstream Flood Control 5. Great East Japan Earthquake December 2012 (Arakawa River Tsunami) Arakawa-Karyu River Office 6. Disaster Management Facilities Use Plan
MLIT Organization
Internal departments/bureaus Number of employees: as of December 31, 2007 Construction and Engineering and Engineering Construction National and Regionaland National Management Bureau Hokkaido Bureau Port and Harbars Port Water and Disaster and Water Maritime Bureau Maritime Housing Bureau Railway Bureau Road Transport PolicyBureau Land Economy and Land Economy Road Bureau Civil aviation Policy Bureau Policy City Bureau Industry Bureau Secretariat Contents Minister Bureau Bureau Bureau MLIT (number of employees: approx. 150,000)
’ s Regional Development Bureaus (number of employees: approx. 22,000)
Facilities Kanto Regional Development Bureau College of Land, Infrastructure and Land, of College Policy Research Institute for Land Institute for Research Policy
1. About the Ministry of Land, College Aeronautical Safety
National Institute for Land and Land Institute for National (number of employees: approx. 4,000) Infrastructure and Transport Infrastructure and Infrastructure, Transport and Tourism Infrastructure Management Transport Kanto Regional Development Bureau (MLIT) (New Urban Center)
2. About the Arakawa River Tohoku Regional Bureau Ministry of Land, Infrastructure, Transport and Special Tourism organizations Kanto Regional Development Ogasawara General Geospatial Information
Accident Tribunal Bureau Authority of Japan of Authority Japan Marine Marine Japan General Affairs Department Office 3. Diverting the Arakawa Planning Department Construction Policy Department River Department Kanto Regional Road Department Development Bureau Saitama New Urban Center Harbor and Airport National Government Bldg. 4. Downstream Flood Control Local Branch Office Department Tower-2 Building and Repair Services Department Regional Transport
Regional Development Development Regional Department Development Bureau Development Aviation Bureaus Hokkaido Regional Hokkaido Air Navigation Navigation Air Regional Civil Regional Land Department Bureau Bureau 5. Great East Japan Earthquake Offices Hokuriku Regional (Arakawa River Tsunami) Development Bureau Chubu Regional Bureau External bureaus Kinki Regional Development Bureau Japan Coast Guard Japan Meteorological Meteorological Japan Japan Transport Japan Tourism 6. Disaster Management Facilities Use Plan Safety Board Chugoku Regional
Agency Development Bureau Agency
Shikoku Regional Development Bureau
Kyushu Regional Bureau Coverage by Regional Development Bureaus Contents
Hokkaido Regional Development Bureau 1. About the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) 8 Regional Development Bureaus Tohoku 2. About the Arakawa River Hokuriku
Kanto 3. Diverting the Arakawa Chugoku Kinki Chubu Kyushu Shikoku 4. Downstream Flood Control 5. Great East Japan Earthquake (Arakawa River Tsunami)
Okinawa General Bureau, Cabinet Office 6. Disaster Management Facilities Use Plan
Arakawa River Basin Basin Overview - Big River Running through Japan's Capital -
Comparison of Basins
Kumagaya City
■ Chao Phraya River Yorii Saitama ■ River head Northern Oashi Bridge Prefecture mountainous region of Thailand Course length 980 km Basin area 157,900 km2 Chichibu City Kawagoe City
Jisui ■ Saitama City Bridge Flood Control Mt. Kobushigatake Reservoir No. 1 Elevation 2,475 m Tonegawa River basin ■ River head Mt. Ominakami Population of flood zones Approx. 5.4 million Iwabuchi Course length 322 km (No. 2) Assets within flood zones Approx. 78 trillion yen Oume City Basin area 16,840 km2 (No. 1) Population Entire basin Approx. 3,100 people/km2 Basin population Approx. 12.14 Drainage divide million (No. 1) density area Arakawa River basin Riverside Approx. 12,900 people/km2 River head Mt. Kobushigatake areas in TokyoTokyo Course length 173km (No. 15) Tokyo Basin area 2,940 km2 (No. 19) (For Average in Japan 340 Basin population Approx. 9.3 million reference) people/km2 (No. 3) In Tokyo 5,460 people/km2 Basin Land Use Overview of Flow Path
43% of the basin is mountainous. 28% is urban. Gunma.pref Kumagaya City Assets within the basin (approx. 32% of entire Kanto Region) total about 150 Gyoda City Musashi Canal R Yorii Town h e o a Nagatoro k d trillion yen. (*Total assets in Kanto equal approx. 462 trillion yen.) u w Nagatoro Town z e o k r Saitama.pref Kounosu k i
City s Ranzan Higashimatuyama Town City Kitamoto City Okegawa City legend Toki gawa River Ageo City rice field Takizawa Dam Hatoyama Nagano Oppegawa Town Futase Dam pref Chichibu river farmland City Sakado Mouth of the Arakawa City mountains Laku Urayama Koazegawa (downstream) Mt Kobushi Oboragawa river Dam Tsurugashi Akigase Intake Weir Chichibu river Komagawa urban areas river ma City Kawagoe City Arakawa river flood control Reservoir others Saitama City Hanno City Sayama Kawaguchi City river/lake City Irumagawa Lake-Sai Yamanashi Ome City river Iruma City Toda City Pref Tokorozawa City Adachi City Itabashi City Kita City Katsushika City Arakawa City Sumida Arakawa-karyu river office City River head Edogawa Chiyoda Tokyo Sumidagawa City その他others City Koto City farmland畑地 11% river 11% Nagatoro (upstream) mountains Iwabuchi 山地 Konosu City rice field 水田 43% (midstream) 7% urban市街地 areas 28% Current Land Use (1997)
River Channel Characteristics Middle Section with Wider Channel The midstream high-water channel measures 2.5 km at its widest point. The diversion channel located 21 km downstream has a width of about 0.5 km. The upstream section leading to Yorii is very steep at 1/10 to 1/400. The midstream section from Yorii to Akigase is sloped at 1/400 to 1/5,000. The downstream slope gradient, from Akigase to the mouth (estuarine basin), ranges from 1/5,000 to 1/10,000.
Distance from the mouth and width Cross section
upstream midstream downstream Fluvial terrace (100 km from the mouth) Arakawa Arakawa river River River
width of of width the river terrace
Flatland (35 km from the mouth) Levee Arakawa Hill River bed gradient river Levee Cross section Cross section Cross section Mt Kobushigatake (100 km from the mouth) (35 km from the (10 km from the mouth) mouth) Urban areas (10 km from the mouth)
Arakawa Sumidagawa river river Urban area
Riverbed incline 62 km from V-shaped valley River Teracce Alluvial Flat land *Based on "Arakawa River Report" the mouth fan Flood Control via Cross Levees Flood Control via Arakawa River Flood Control Reservoir No. 1
26 cross levees have been built along the wide reach of the Levee river between Nukata Bridge in Yoshimi-cho and Sasame Retarding Bridge in Toda City for better water flow diversion to control flood Cross downstream. Dike
Floodwater overflowing into the Arakawa Arakawa River Flood Control Reservoir No. 1 ‘
River s low- Reservoir No.1 Arakawa River Levee water channel ↓ Levee
↑During flood (Yoshimi-cho, Konosu Under normal conditions (Yoshimi-cho, overflow levee City), photo taken in September 1982 Konosu City) →
Extensive Zero-meter Zone Ground Subsidence due to Pumping of Groundwater
Industry stops using well water (Koto area) Pollution prevention ordinance revised Designated under the Industrial Water Act (Koto area) Natural gas extraction discontinued Korean War begins Industry stops using well water (Edogawa Ward) Great Kanto Earthquake World War II ends Industry stops using well water (Johoku area) Below high-water level: 124.3 km2 (Population: Approx. 1,760,000) Cumulative sinkage (m) (m) sinkage Cumulative
Below low-water level: 31.5 km2 (Population: Approx. 400,000) Benchmark Cumulative Year Benchmark location sinkage (m) measuring number begun Legend Minamisuna 2-chome, Koto Ward 1918 Areas above high-tide level that are Kameido 7-chome, Koto Ward 1892 prone to storm surges (A.P. +5.0 m) Mukai Tachibana 6-chome, Sumida Ward 1935 Areas below high-tide level (A.P. +2.0 m) Nakakasai 3-chome, Edogawa Ward 1918 Senjunakacho, Adachi Ward 1892 Areas below low-tide level (A.P. +0m) Shimizucho, Itabashi Ward 1932 Major (See section on low- benchmarks lying land subsidence) Pumping Keeps Water Level below Sea Level in Zero-meter Zone Koto Delta There is up to a 3.1 m difference in water levels in the area of the Koto Delta sandwiched by the Arakawa and Sumidagawa Rivers.
Sumidagawa River Arakawa River Katsushika City
Arakawa City
Sumida City Taito City P Mean high tide A.P. +2.1 m
A.P. ± m
West side East side Chuo City P
Arakawa Lock Gate Zero-meter zone Edogawa City Koto City
Arakawa Lock Gates Anti-storm Surge Projects
The Arakawa Lock Gates were completed in October 2005. Serving as part of a wide-area disaster management network, the lock gates ☆ History of storm surge planning enable transport of relief supplies and disaster victims during emergencies to aid ・Storm surge preparedness plans were relief activities. developed by municipalities throughout Japan In normal times the lock gates provide opportunities for water activities such as after Typhoon Vera left a path of destruction sightseeing cruises, canoeing, boat regattas, etc. along Ise Bay in 1959. ・Specifics of the preparedness plan for Tokyo Bay were finalized in 1960.
☆ Overview of anti-storm surge projects ・Projects were initiated in 1961 based on the Anti-storm surge facilities constructed master storm surge preparedness plan for Tokyo Bay. ・The plan for the Arakawa River Diversion Channel included constructing a right bank storm surge barrier (from the river's mouth to Front lock gate Sumida Floodgate) by FY1965 and a left bank storm surge section by 1970. 20 Aerial view of the Arakawa Lock Gates Arakawa River's storm surge barrier Overview of Riparian Restoration Project Riparian Restoration/Conservation (Komatsugawa Area Test Site) Example of implemented project: Komatsugawa area [Vertical river wall was removed and gradually sloped river front was built.] The existing river wall separating the river and its bank by sheet piles and concrete blocks was removed, and the river front was gently sloped to restore reed field and tidal flat. Wood-framed river mattresses were laid to test how well they would dissipate waves generated by boats and prevent erosion of the reed field/tidal flat.
Wood-framed river mattresses (Fragments of concrete blocks once used for bank protection are Covered with reused as filling.) soil available on site (Immediately after construction, 2004) (Before construction) Gabions installed (Fragments of concrete blocks once used for bank protection are reused as filling.)
Steel sheet piles reused as foundation
(2008) Existing river wall was removed to restore reed field and tidal flat.
River Stations (Emergency Docks) Emergency River Bank Road
● Designed for rescue ops and loading/unloading of supplies, machinery, food, etc. ● during an emergency. The emergency river bank road connecting river stations serves as an emergency supply route. ● The road stretches from the river mouth to Hanekura Bridge (about 37 km). ● Can be used as public docks for boarding/disembarking water taxis, etc. <12 under the plan, 9 constructed, 1 under construction> a d a c h H i o r K i k a i r w i a g O u g c i h i S e n j y u T I w o a d S b a u h c i n h d i I e t a n b a s h i K o R m i n a k t s a u i g a w a S h i n s u n a
Quays type pontoon type
constructed constructed Under the Under the plan plan The Tokyo leg is completed. 57.0-km (98%) of the 58.2 km road has been constructed. Under Under construction construction The remaining 1.2-km section will be constructed on the river's left bank in Kawaguchi City, Saitama Prefecture in step with construction of the super levee project. Seismic Strengthening of River Structures (Level 2) Rapid Urbanization during Economic Boom
Along the Arakawa River today (2006) - Preparing for Earthquakes -
☆ Earthquake-proofing river structures (L2-resistant) Super levee in Hirai 7-chome area River structures (floodgates, pipes, pumping stations, docks, etc.) are being reinforced to make them resistant to Level 2 earthquake motions (the largest 1882 37 years possible). Earthquake-proofing of the Ayasegawa Pumping Station began in FY2010. 1919 35 years Earthquake-proofing of the Sumida, Sanryo and Sasame Sluicegates began in 42 years FY2012. 1954 1996
Sanryo Water gate Shibakawa Ayase Drainage Ayase Sluice gate Pump Station Sluice gate Saitama Matsudo
Sumida Sasame Sluice gate Sluice gate Iwabuchi River Edogawa Sluice gate
Nakagawa
Sluice gate Arakawa River
Shin-shibakawa Horikiri-syobu Drainage Pump Station Sluice gate Tokyo
Reinforcing a river structure against bending and shear failure (Steel-plate lining) River structures requiring seismic Arakawa River Diversion Channel completed in 1930 strengthening (sluicegates) 25
The Big Flood of 1910 In addition to the continual rain beginning in early August, there were heavy rains Contents ranging from 300 mm to 400 mm in the mountains of Chichibu from August 8 to 10. Levee breaches: more than 10 locations
1. About the Ministry of Land, Deaths: 369 (including fatalities in areas along Infrastructure, Transport and Tourism the Tonegawa River) (MLIT) Victims: 1.5 million Houses washed out/destroyed: 2. About the Arakawa River 1,679 units Houses inundated: approx. 3. Diverting the Arakawa 270,000 units Total damage accounted for approx. 4.2% of gross national 4. Downstream Flood Control income Honjominamiwari (now Kinshicho) 5. Great East Japan Earthquake (Arakawa River Tsunami)
Affected area 6. Disaster Management Facilities Use Plan Inundation depth approx. Area affected by the flood of 1910 1.5 m Damage Caused in 1910 Construction of Arakawa River Diversion Channel
Arakawa River Diversion Channel constructed
Iwabuchi Following the devastating Floodgate Construction underway flood of August 1910, the Arakawa River Diversion Channel (today's Arakawa River) was constructed to protect Tokyo. Flooded Asakusa Park (photo courtesy of Rinnosuke Houses submerged in muddy water (Sumida-mura) Shimokawa) Arakawa River Length: 22 km before trenching (Current Arakawa River) Width: 500 m Cost: Approx. 230 Current Arakawa River billion yen Imperial Palace (Construction period: 20 years)
Started in 1911 Completed in 1930 Devastation in Honjominamiwari (now Kinshicho) Inundation depth approx. 1.5 m
Photos of Arakawa River Diversion Channel Construction Contents
1. About the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) 2. About the Arakawa River 1. River banks were leveled by human and 2. A channel was excavated using a steam horse power. excavator. 3. Diverting the Arakawa
4. Downstream Flood Control 5. Great East Japan Earthquake (Arakawa River Tsunami) 6. Disaster Management Facilities Use Plan
3. After water had been drawn into the31 channel, the channel bed was dredged. Arakawa River during flooding Arakawa River under normal conditions (August 1999)
Gauging station Gauging station
Iwabuchi Floodgate
Iwabuchi Floodgate Sumidagawa River Arakawa River Arakawa River 30% (diversion channel) (diversion channe 70% Sumidagawa River 0% 100%
Standard Downstream Water Levels and Discharges August 1999 Flood at Iwabuchi (Upstream) Gauging Station
Peak flow (at Shin-arakawa Ohashi Bridge) 4,700 m3 Distribution of design flood discharges (revised in 1973)
Levee height Peak basic flood discharge (revised in 1973) A.P. +12.5 m
Water level for operating Iwabuchi Floodgate: AP +4.0 m
1947 Typhoon Kathleen (8.60 m) Design flood level A.P. +8.57 m 1958 Typhoon Ida (7.48 m) Bankfull stage A.P. +7.70 m 1999 tropical storm and heavy rain Iwabuchi Floodgate (AP (6.30 m) ＋ ｍ 4.0 ) fully closed 2007 Typhoon Fitow (5.09 m)
Warning stage A.P. +4.10 m
Flood response alert stage A.P. +3.00 m At spring tide A.P. +2.10 m Normal level at Iwabuchi Floodgate (Upstream) Major Typhoons after Completion of Diversion Channel Without Arakawa River Diversion Channel - 1947 Typhoon Kathleen -
1947 Typhoon Kathleen
Design flood level (AP +8.57 m) 1941 typhoon
Bankfull stage (AP +7.70 m) 1928 typhoon 1958 Typhoon Ida Evacuation stage (AP +7.00 m)
1999 tropical storm and heavy rain
1938 typhoon
Distribution of maximum inundation depths
Levee Breach Levee Breaks Produce Quick Flooding - Plans
As the water level rises, the levee needed to Evac Crowded Areas As it rains, the water held back by the levee rises. River water seeps into the levee. weakens and is easily breached. Process of levee failure Location of levee breach
30 minutes
1 hour
Slope on residential area side: about 30 2 hours degrees (1:2) Slope on river side: about 30 degrees (1:2) Levee material: coarse sand 3 hours Scale: about 1/50 6 hours
Number of people affected* Approx. 1.2 million 12 hours Inundated area Approx. 110 km2 Deaths* Approx. 2,000 Maximum number of Approx. 860,000 (1 day later) 18 hours isolated victims* Legend 24 hours Approx. 510,000 Estimated inundation Inundation above floor depth (by rank) Number of level: Approx. 450,000 Below 0.5 m households households 0.5 m - 1.0 m inundated Inundation below floor 1.0 m - 2.0 m
level: Approx. 60,000 2.0 m - 5.0 m
households 5.0 m or higher Subway stations inundated: Ginza, Tokyo, Akihabara, etc. Subways and Underground Malls Flood First What Would Happen If a Levee Broke?
Inundation depth above ground If the Arakawa River 1 mm - 0.5 m 0.5 mm - 1.0 m flooded, 19 subway lines 1.0 mm - 2.0 m (about 110 stations) and 2.0 mm - 5.0 m 5.0 mm or higher underground malls located within the flood zone would be inundated.
Machiya Station Major underground facilities likely to be inundated: Tokyo Metro Ginza, Marunouchi, Tozai, Hibiya, Chiyoda, Yurakucho, Hanzomon, and Nanboku Lines; Toei Shinjuku, Oedo, Asakusa, and Mita Lines; JR Yokosuka, Sobu, Keiyo Lines; Keisei Oshiage Line; Tobu Isezaki Line; Saitama Rapid Railway; Tsukuba Express; Yaesu and Asakusa underground Subway inundation shopping malls Full (water reaches top of a station or tunnel) Inundated (water depth exceeds 2 m) Inundated (water depth exceeds 5 m) No inundation Simulated inundation (Ginza)
Super Levees Construction of Super LeveesOverview of super levee
☆ What is a super levee? A levee whose width is about 30 times its height (10 m high = 300 m wide)
High-Standard Embankment(“Super levee”) Area of super levee construction integrated into community development
Special super levee development zone: 30h (30 Levee height (h) times the height of the levee) River Reservation
☆ Features ・ Earthquake-resistant ・ Resistant to overflow ・ Resistant to seepage Super Levee Construction in Komatsugawa Super Levee Construction in Komatsugawa (Photos)
[About the project] A super levee is being constructed in tandem with the Tokyo
: Construction area
[Location] Edogawa Ward, Tokyo [Project details] ○ Construction period: FY1990 - FY2014 ○ Area: Approx. 25 ha ○ Length: Approx. 2,380 m
[Related projects] Photo taken in January 2010 ・ Class 2 urban redevelopment project in Kameido, Oshima and Komatsugawa (Tokyo Metropolitan Government) [Standard cross-section] ・ One thousand cherry tree planting project in Edogawa Ward (Edogawa Ward) ・ Renovation of Komatsugawa Daini Elementary School (Edogawa Ward) ・ Public housing construction project (Tokyo Metropolitan Government) ・ Construction of Komatsugawa Junior High School (Edogawa Ward)
The Future of Super Levee Construction Levee Reinforcements
☆ In October 2010, the national government's Government Revitalization Unit asked that the plans for building super levees be revised due to the enormous time and money they required.
☆ [A group of experts who reviewed the super levee construction plans made the following proposal] Construction of overflow-resistant super levees should focus on protecting lives. They should be built only along densely-populated areas to prevent the massive death and destruction that could result from a levee failure. Measures to reinforce existing levees Section bordering Toda Park in Toda City Section bordering Shingashi, Itabashi Ward along other sections should be actively implemented in order to make them resistant to Section bordering Kohoku, Adachi Ward seepage and erosion (not overflow) and enhance the level of safety in these areas ASAP. Before reinforcing During reinforcing After reinforcing
[Criteria for building super levees] Asphalt pavement Sections where a levee failure would result in: Lawn 1. inundation of land below sea level before people there could evacuate Lawn 2. inundation up to the second floor of buildings in densely built-up areas Soil retention liner Articulated concrete blocks + 3. destructive flooding, resulting in damage to densely built-up areas along the river impermeable liner Sections where super levees should be built shall be determined on the basis of the above Levee base criteria in light of flooding and topographical conditions, etc. drainage ditch Sections of the Arakawa River include: ・Right bank: Tokyo Metro Tozai Line bridge (Koto Ward) - Sasame Bridge at National Route 17 bypass (Itabashi Ward) ・Left bank: Tokyo Metro Tozai Line bridge (Edogawa Ward) - confluence with the Landside drainage Shobugawa River (Kawaguchi City) Levee Reinforcement Sections Contents
1. About the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) 2. About the Arakawa River
3. Diverting the Arakawa Flood tide section (No anti-seepage measures) 4. Downstream Flood Control [Legend] (As of October 2012) 5. Great East Japan Earthquake : Completed (Arakawa River Tsunami) : Not completed : To be completed in FY2012 6. Disaster Management Facilities Use Plan (including projects carried over from FY2011) : Sections designated for super levees
Overview of Great East Japan Earthquake Earthquake-triggered Tsunami Date/time: 2:46 p.m., Friday, March 11, 2011 Epicenter: Off the coast of Sanriku (about 130 km ESE of Ojika Peninsula) Magnitude 9.0 Maximum seismic intensity (Japanese shindo scale): 7 (Kurihara City, Miyagi Prefecture) Seismic intensity of 6+ was recorded in 28 municipalities in Miyagi, Fukushima, Ibaraki and Tochigi Prefectures.
■ 沿川２市７区の最大震度7wards and 2 cities along the river
【本震】3月11日14時46分【main shock】 March 11 14:46 【埼玉県】 【Saitama Prefect.】 戸 田 市 上戸田 、川 口 市 中青木分室 Kamitoda, Toda-shi / Nakaaoki-bunsitu, Kawaguchi-shi 【【東京都】Tokyo】 5-upper５強 Chuo,江 Edogawa-ku戸 川 区 中央、 / Senjyunakai-cyo足 立 区 千住中居町、神明南 Shinmeiminami, Adachi-Ku板 橋 区 / Takashimadaira,高島平、 Itabashi-Ku Touyou江 東 Ojima(Onagi区 東陽、大島（小名木川出張所） River Branch Office), Koto-ku / Shimo, Kita-ku(Arakawa-karyu River Office) 北 区 志茂（荒川下流河川事務所） Kanamachi Tateisi, Katsushika-Ku / Higashimukoujima, 5-lower５弱 葛 飾 区 金町、立石、墨 田 区 東向島、北 区 赤羽南 Sumida-Ku / Akabaneminami, Kita-Ku
【After【余震】11日15時15分 shock】 March 11 15:15
5-lower５弱 Cyuo, Edogawaku 江 戸 川 区 中央 Source: Prof. Takashi Furumura and Takuto Maeda (project researcher), Earthquake Research Institute, University of Tokyo Impact of the Earthquake (Arakawa River Water Levels) Change in River Water Levels Due to Tsunami (Minamisunamachi)
Iwabuchi Floodgate (Upstream) ■ Minamisunamachi Gauging Station (Minamisunamachi, Koto Ward), 0 km from the river mouth Minamisunamachi Gauging Station 2.5 Earthquake hit Estimation*1
2
1.5 7.5 km 21 km
1 Minamisunamachi Gauging Station 0.5
0
Iwabuchi Floodgate 12:00 0:00 12:00 0:00 12:00 (Upstream) Gauging Station
Sasame Gauging Station 1.00 Max. 0.8 m 0.80
0.60 Sasame Gauging Station 0.40
0.20 Minamisunamachi Gauging Station 0.00 Minamisunamachi Gauging Station -0.2012:00 0:00 12:00 0:00 12:00
-0.40
-0.60
-0.80 Minamisunamachi -1.00
Change in River Water Levels Due to Tsunami (Iwabuchi Sluicegate) Change in River Water Levels Due to Tsunami (Sasame) ■ Iwabuchi Sluicegate (Upstream) Gauging Station, 21 km ■ Sasame Gauging Station, 28.5 km from the river mouth Sasame Gauging Station from the river mouth Iwabuchi Sluicegate (Upstream) Gauging Station Estimation Estimation
2.50
2.50 Sasame Gauging Station 2.00 Iwabuchi Sluicegate (Upstream) Gauging 2.00 Station 1.50
1.50 1.00
1.00 0.50
0.50
0.00
0.00 12:00 0:00 12:00 0:00 12:00
Iwabuchi Sluicegate (Upstream) Gauging Station 12:00 0:00 12:00 0:00 12:00 1.00 1.00
0.80 0.80 Sasame Gauging Station 0.60 0.60 0.40 0.40 0.20 0.20 0.00 0.00 -0.2012:00 0:00 12:00 0:00 12:00 -0.2012:00 0:00 12:00 0:00 12:00 -0.40 -0.40 -0.60 -0.60 -0.80 -0.80 -1.00 -1.00 Tsunami Propagation Speed (River's Mouth to Sasame) What the Floodgate Did
■ Tsunami finally reached the Akigase Intake Weir located about 35 km from the river's ■ Shibakawa Floodgate (Kawaguchi City, Saitama mouth. Prefecture), about 20 km from the river's mouth
2.5
21 km 13.75 km Earthquake hit
28.5 km Shibakawa Sluice gate 2 Shibakawa Sluice gate Arakawa River (Back) Gauging Station Closed Sasame Gauging Station
1.5
Shinshibakawa River Approx. 25 km/h 1 6:20 p.m. March 11 Shibakawa Floodgate Shibakawa Sluice gate (Front) Gauging Station 0.5
0 Floodgate operation 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00 Operation Status Operation操作開始 start 操作完了completion 状態 11日15:20 11日15:47 shut-off全閉 5:10 p.m. March 11 Ayase綾瀬水門 Sluice gate Shibakawa Sluice gate (Front) Gauging Station 12日14:00 12日14:30 Fully全開 opening Shibakawa Sluice gate (Back) Gauging Station Minamisunamachi Gauging Station 11日15:18 11日15:30 shut-off全閉 Nakagawa中川水門 Sluice gate 0 km 12日14:00 12日14:30 Fully全開 opening 11日16:40 11日16:50 shut-off全閉 Sumida隅田水門 Sluice gate 12日14:00 12日14:10 Fully全開 opening
11日16:45 11日17:40 shut-off全閉 Shibakawa芝川水門 Sluice gate 12日14:00 12日17:30 Fully全開 opening
Iwabuchi岩淵水門 Sluice gate No操作無し operation No操作無し operation Fully全開 opening
荒川ロックゲArakawa Lock gate ート 〃 〃 shut-off全閉
Now and in the Future Current status Contents The Arakawa River's banks are designated as evacuation sites by local municipalities. In Tokyo alone, these sites are expected to be used by up to 600,000 evacuees in the event of a major earthquake. An emergency river bank road and river stations (docks) have been constructed along 1. About the Ministry of Land, the river. These facilities are included in Tokyo's regional disaster management plan and serve as an emergency transport route. The river's high water channel is Infrastructure, Transport and Tourism positioned as one of the candidate sites for emergency operations in the Central Disaster Prevention Council's plans for measures against inland earthquakes in the (MLIT) Tokyo metropolitan area. 2. About the Arakawa River Tasks ahead Since no specific rules for using these facilities have been developed, congestion or confusion may occur and hinder their effective use, especially during the initial stages of 3. Diverting the Arakawa a disaster when river administrators are unable to perform on-site control.
River bank Emergency river bank road River station (dock) 4. Downstream Flood Control 5. Great East Japan Earthquake (Arakawa River Tsunami) 6. Disaster Management Facilities Use Plan Planning Overview Planning Method, Members, etc.
Objective Planning method Develop a plan for using disaster management facilities in the event of a major Planning via workshops with disaster management officers from organizations in charge of earthquake in the northern Tokyo Bay area or other areas in order to ensure that disaster relevant disaster management facilities under their regional disaster management plans and management facilities under the jurisdiction of the Arakawa-Karyu River Office will be organizations that are expected to use these facilities. effectively used by disaster response organizations and to ensure emergency Workshops provide opportunities to freely express opinions outside the confines of particular transportation, recovery operations, etc. for quick disaster response. occupational responsibilities. Agenda 1. Locations and ways to use the Arakawa River Members (FY2010 and onward) → Zoning banks Disaster management officers from the Tokyo Metropolitan Government, Saitama Prefectural Government, municipal governments of 2 cities and 7 wards along the river (Kawaguchi and Toda 2. Basic rules for using disaster management facilities → Operations manual Cities, Sumida, Koto, Kita, Itabashi, Adachi, Katsushika and Edogawa Wards), police departments, fire departments, Self-Defense Forces (JSDF), and Arakawa-Karyu River Office 3. Sharing of information about damage to disaster → Information sharing Experts, etc. management facilities and how facilities are being used organization [Chief] FY2010 ・Toshiyuki Shikata (Professor, Teikyo University, Advisor to the Tokyo Metropolitan Government) [Facilitators] FY2008 - FY2012 Be as prepared as possible! ・Takaaki Kato (Associate Professor, International Center for Urban Safety Engineering, Institute of Industrial Science, University of Tokyo) ・Hitoshi Nakamura (Professor, Architecture and Environment Systems Department, College of Systems Engineering and Science, Shibaura Institute of Technology) Develop a plan for using disaster ・Tadahiro Yoshikawa (President, Laboratory of Urban Safety Planning Co., Ltd.) management facilities along the Arakawa ・Akihiko Nunomura (Visiting Professor, Kansai University) *Starting in FY2011 River's downstream reach.
Council to Implement Downstream Arakawa River Disaster Management Facilities Use Plan Outline of Operations Manual
Phase 1 1 day from disaster Phase 2 3 days later Phase 3 Day 3 and after Top priority: Emergency care and rescue Give priority to firefighting operations when water is needed to prevent fire from spreading. Use as an evacuation site Remaining Mobility for people who Use to store supplies evacuees have difficulty returning High Give priority to emergency vehicle traffic in order to transport the injured, sick, medicine, etc. home Can't unload! No place to dock! priority Danger! 1. Recovery of river facilities Danger! When river disaster management facilities are damaged by an earthquake and cannot be used, give priority to river administrator's recovery operations. Danger! 2. Mobility of wide-area relief/rescue teams Uses by wide-area relief/rescue teams from the JSDF, police and fire departments entering the affected area.
Blocking the way! Danger! 3. Transport of emergency relief supplies Use the emergency river bank road for emergency vehicle traffic when it will speed up delivery of Inspections/patrols Emergency Emergency vehicle Remaining Use as an emergency repair work route evacuees transportation route relief supplies to affected area. 4. Transport of disaster recovery materials/equipment Use the emergency river bank road and emergency docks when it will speed up the transport of Low disaster recovery materials/equipment. Downstream Arakawa River Disaster Management Facilities Use Plan (Draft) priority developed 5. Other uses When water is needed for firefighting purposes after fires are put out or if there is a need for using the Includes basic policies for emergency response organizations to effectively use the Arakawa River river facilities for other purposes, their use will be coordinated by the users. facilities as well as examples of specific emergency responses. Revision to Downstream Arakawa River Disaster Management Disaster Drills Using Arakawa River Facilities Facilities Use Plan Downstream Arakawa River Disaster Management Facility Tested during 24JXR (joint ops including Japan Ground Self-Defense Management Council established Force, MLIT and police) The council oversees the workshops. JSDF conducted joint disaster drills (command post exercises) based on a metropolitan earthquake Matters discussed in the workshops are brought to the council. The council then decides what to scenario. The drills were designed to test the proposed revisions to the JSDF's metropolitan earthquake incorporate into the plan, which is then put into operation on a trial basis. response plan and to maintain/enhance the JSDF's ability to respond to earthquakes. ■ Council meeting held ■ Drills included: Use of alternative transport routes in Tokyo while disaster- Use of the Arakawa River as Wednesday, February 22, 2012 (held annually) affected roads are being cleared an emergency transport ■ Council members Transport routes to quickly deliver heavy equipment to road/channel disaster area Tokyo Metropolitan Government (disaster management department head), Saitama Prefectural Government (disaster management department head), municipal governments of 2 cities and 7 wards (risk management/civil engineering department heads), police departments (disaster management department head), fire departments (disaster management department head), JSDF (First Division G- 3 chief), Arakawa-Karyu River Office (director) Revising the Facilities Use Plan Workshop participants continue to discuss outstanding issues, problems that arise after implementation of the draft plan, areas that need to be revised due to changes in relevant organizations' plans (for accepting relief assistance, emergency road networks, etc.) and so on.
■ Meeting to okay workshop proposals ▲ Police officers handing over operations to MLIT ▲ Connecting boats for transporting Members: disaster management officers Facilities Use Plan after leading emergency vehicles through town heavy machinery (Draft) Start implementing Council Ongoing discussion to keep the plan alive Feedback Disaster management personnel Facilities Use Plan meet face to face (Build stronger ties) Parts of the plan that can be implemented
Workshop ■ Meeting to discuss specifics of the Facilities Use Plan Members: officers in charge of disaster management operations ▲ Police car leading emergency vehicles along the river bank. ▲ Transporting heavy machinery
Thank you for your participation.
The end! Thank you!