1 Sustainability 2012, 4, ; doi: /su Concept Paper OPEN ACCESS sustainability ISSN From Confining to Sharing for Sustainable Flood Management Guangwei Huang Graduate School of Global Environmental Studies, Sophia University, 7-1 Kioicho, Chiyoda-ku, Tokyo , Japan; Tel.: ; Fax: Received: 13 April 2012; in revised form: 29 May 2012 / Accepted: 18 June 2012 / Published: 26 June 2012 Abstract: It is widely accepted that sustainable development is the development that meets the needs of the present without compromising the ability of future generations to meet their own needs. However, the question of how to apply this principle to flood management remains insufficiently answered. This article outlines a new strategic concept termed as Flood Sharing as a means toward sustainable flood management. Contrary to the traditional concept of flood confinement or blocking, the new concept advocates the need to alleviate flood damage by reducing inundation depth via expanding flood inundation areas. It differs from other contemporary thinking such as make space for water and room for the river in its emphasis on using the urban fabric. Evidence from a case study was presented to support this new concept, and model/data analyses have been conducted to show that it could be realized through the wise use of infrastructure. Keywords: flood confining; flood sharing; inundation area; multi-purpose roads 1. Introduction Flooding is one of the major natural hazards that human beings have been coping with for centuries. What is the current situation? By any number of accounts, the world in general appears to be facing even greater challenges from flooding today than it did a generation ago. For instance, the Venezuela floods in December 1999 cost over 30,000 lives, destroyed 23,200 houses, and damaged another 64,700 . In 2010, Pakistan was awash with the worst flooding in more than a century, leading to at least 1600 deaths and 12 million affected. The United Nations has rated the floods in Pakistan in 2010 as the greatest humanitarian crisis in recent history . In 2011, Flood waters in Thailand have swamped more than two-thirds of the country, submerging rice fields and shutting down hundreds of
2 Sustainability 2012, factories, while over 900,000 families and businesses have been impacted and hundreds of lives have been tragically lost. These are good examples of the escalated severity of flood disasters. The intensifying flood impacts are often attributed to urbanization across the world. Urban watersheds, on an average, lose 90% of the storm rainfall to runoff, whereas the non-urban forested watersheds retain 25% of the rainfall . A new dimension of challenges is the increase of flood risk due to climate change. According to an IPCC report, both floods and droughts will become more severe in areas that are already prone to such disasters. In developed counties such as Japan, however, flood disasters exhibit two trends. As shown in Figure 1, there is a decreasing trend in the inundation area and an increasing trend in the flood damage density (million JPY per ha) over the last several decades. This contrast is often explained as being caused by urbanization, which led to the concentration of assets in flood-prone areas. Figure 1. Trends of inundation area and damage density in Japan. Inundation area (ha) Inundation area Damage density Damage density (million JPY/ha) Traditional flood management approaches focused on reducing flooding and reducing the susceptibility to flood damage through structural countermeasures. These were often ad hoc reactions and carried out in isolation. Flood confinement or blocking may be considered as the keywords to describe traditional flood management. For instance, ring dike and double-dike have been used to prevent flood waters from entering certain target area. The Netherlands is well known for its wide use of the ring dike approach . As a result, the entire nation has been subdivided into dike-ring areas. The use of ring dike in Japan has a long history as well, dating back to the 16th century. Noubi plain is famous in Japan for the large number of dike rings constructed during the Edo Era . Another traditional countermeasure is the so-called double-dike, which was first used in the Yellow River in China dating back to the North Song Dynasty ( ) and also used in Japanese rivers since the Edo Era . In recent years, ring dike and double-dike have been highlighted again in Japan as important techniques toward the realization of the concept of living with floods . More broadly speaking, storage tanks, constructed wetlands, retention ponds, dike rings and double-dikes have been viewed as the state of the art for flood risk reduction. A common concept inherent in these approaches is to localize floods or block flood waters from entering certain areas. In the Netherlands, the design of dikes is linked to the frequency of occurrence of a certain flood stage.
3 Sustainability 2012, The particular frequencies of occurrence, or risk levels, are determined by the national Parliament. Levees along the coasts of densely-populated and highly industrialized parts of the country are to be designed to protect from all storms whose magnitudes would be exceeded only once in 10,000 years on average. It is a traditional mindset that higher dikes are safer. However, in reality, higher and higher dikes would result in unjustifiable risks in the event of a dike breach. When a dike breaks, this flood defense structure does not act as a protection, but rather as an amplifier of destruction. During recent decades, the concept of integrated flood management for sustainability has been gaining momentum. It calls for a paradigm shift from the traditional, fragmented and localized approach, and encourages the use of the resources of a river basin as a whole, employing strategies to maintain or augment the productivity of floodplains, while at the same time providing protective measures against losses due to flooding. However, sustainable flood management (SFM) is not well-defined and may mean different things to different people. The following definition of SFM was proposed by the National Technical Advisory Group of Scotland (NTAG): Sustainable flood management provides the maximum possible social and economic resilience against flooding, by protecting and working with the environment, in a way which is fair and affordable both now and in the future. Delft Hydraulic Laboratory  proposed a sustainability checklist embracing five main criteria for the evaluation of flood protection systems as described below: Socio-economic aspects and impacts on growth, resilience and stability; Use of natural and environmental resources, including raw materials and discharge of wastes within the carrying capacity of natural systems; Enhancement and conservation of natural and environmental resources; Public health, safety and well being; Flexibility and sustainability of infrastructural works, management opportunities for multifunctional use, and opportunities to adapt to changing circumstances. Samuels  suggests sustainable flood defenses should involve: Ensuring quality of life by reducing flood damages but being prepared for floods Mitigating the impact of flood defense activities on ecological systems at a variety of spatial and temporal scales The wise use of resources in providing, maintaining and operating flood defense infrastructure maintaining economic activity (agricultural, industrial, commercial, residential) on the flood plain. In my opinion, for flood management to be truly sustainable, it must balance between flood protection for the present generation and leaving a sufficient degree of freedom to future generations with regard to flood management practice, because we do not know what future generations will want or value, and what technologies future generations will have; some of today s management objectives and practices may be wrong or may change over time. Therefore, flexibility or reversibility should be considered as a minimum requirement of sustainable flood management. It is an extremely important but very much neglected aspect in watershed management so far. Reservoirs are practically irreversible although removal is technically possible. The total cost of removing a large-scale dam could be too expensive to be practicable.
4 Sustainability 2012, A good sign in the Netherlands is that the traditional approach of building tall walls to contain river water has been under re-evaluation in favor of an initiative known as Room for Rivers, which reconnects the river channel with its surrounding floodplain by establishing empty, floodable areas on the riverbanks . In the U.K., the strategic direction of Making Space for Water  was published in 2004, which addresses issues such as land-use planning, giving priority to locating development in areas at a lower risk of flooding, the creation of wetlands, levee setback, restoration of flood plain and funding as well. In the U.S., the government of Iowa City purchased and demolished homes in the 100- year floodplain after the 2008 floods, using the Federal Emergency Management Agency s (FEMA) Hazard Mitigation Grant Program . It effectively reduced the number of local flood prone residences and these areas are now being used as neighborhood parks. These initiatives are important steps toward the establishment of flood resistant and flood resilient societies. However, a common limitation of these concepts and initiatives is that they place the emphasis on restoring or increasing the capacity of flood plains to accommodate more flood waters so that they can be viewed as a clean-up of riparian zones for floods. However, attention given to and efforts exerted towards dealing with residual risk in the context of sustainability are limited. Residual risk refers to the risk of flooding that exists in an area from potential floods that exceed the design of current protection systems, due to the chance that the existing system could experience an unexpected failure. The protection system usually indicates structural measures such as dam, levee and drainage facility. Non-structural measures such as room for the river can now be viewed as part of the protection system. In spite of various structural and non-structural measures on planning and operational level, residual risk cannot be eliminated totally. Extremely large floods, which become highly possible due to climate change, would cause overflow and inundation in urbanized areas anyway. Furthermore, in highly-populated urban areas such as Tokyo and Yokohama in Japan, there is much less room for maneuver using the European approach of clearing riparian zones for greater floodwater storage. Therefore, a new concept is needed for innovating flood management to cope with residual risk that can be relayed to future generations without depleting their choices. In this study, the focal point is to establish a new concept towards dealing with the residual risk that can meet the requirement of reversibility and can work under land availability constraints. The present paper is structured as follows: Firstly, it explains the situation described in Figure 1 from a new perspective. Secondly, it reasons that strategies different from enclosure or blocking and clean-up of riparian zones should be explored, and then it presents a new framework with innovative thinking towards the realization of living with floods. 2. Materials and Methodology The statistical survey on flood damage in Japan started from 1875 but was suspended during World War II. The present form of flood-related statistics published by the Ministry of Land, Infrastructure, Transport and Tourism of Japan had its origin in The annual report includes flood fatalities and numbers of injured; the amount of damage to general assets, such as houses and household goods; the amount of flood damage to public civil engineering works, such as roads, and public utilities, such as electricity and gas; the amount of damage to agriculture; the inundation area; the number of damaged houses and households; the amount of damaged general assets by municipality, and so forth.
5 Sustainability 2012, Besides, municipalities have also been keeping records of flood events that occurred in their administrative areas. The national archive of flood damage surveys, municipal records and results of previous research have been combined to provide evidence and reasoning that confining or blocking of flood waters could be a problem instead of being a solution in an urban context; and to explain the fundamental difference between the concept proposed in this work and other existing contemporary ones. In addition, numerical simulations have also been performed with a so-called Hybrid Model to give supplemental support for the new framework. The Hybrid Model combines 2-D simulation for overland flow with 1-D modeling for flow along roads . The 1D/2D coupling resembles the one employed in LISFLOOD-FP . The general structure of the model is described in Figure 2. Figure 2. Essential architecture of the hybrid modeling system. Hybrid model Elevation of mesh Elevation along roads 2-D simulation 1-D simulation for roads Output Mesh-based flow distribution Road-based flow distribution Land-use 3. Evidence and Reasoning As shown in Figure 1, there is a decreasing trend in the inundation area of Japan over the last several decades. However, the flood damage density has been increasing. This contrast is often explained as due to the concentration of assets in flood-prone areas and the increase of surface imperviousness. Nevertheless, a review of flood events occurring in Japan over the past several decades has revealed that flooding was often a rural phenomenon and due mainly to levee breach or overflow before the 1970s, but turned out to be a more urban event since the late 1980s, due largely to waterlogging. Figure 3 shows that the number of levee breaches has been significantly reduced. The shift of flooding from rural to urban may be attributed to urban sprawl. Urbanization in Japan evolved from 18% in the 1920s to less than 40% in the 1950s, and then rapidly increased since the middle of the 1960s and reached more than 70% in the 1970s (based on the Population Census of Japan). In urban areas, in addition to the problems of asset concentration and surface imperviousness, complex urban structures may exert significant impacts on the behavior of flood waters in case of inundation. Either intentionally or by chance, roads, railroads and building may function as barriers to flood water spreading. Consequently, it may affect the trend of change in flood inundation areas. As an example, Figure 4 shows that the recent flooding events in the Shinjuku district of Tokyo were confined and scattered.
6 Sustainability 2012, Figure 3. Change in the number of levee breaches in Japan Number of levee breach Year Figure 4. Recent flooding records in the Shinjuku district of Tokyo. When flood waters are confined, inundation depths increase. Duiser  proposed a model that relates the local mortality fraction to inundation depth. The work of Waarts  indicates that mortality is an exponential function of water depth. Jonkman  presented a relationship between water depth and mortality for the Orleans and St. Bernard bowls for the flood caused by Hurricane Katrina in the New Orleans. Meanwhile, research on the relationship between property damage and inundation depth has also been conducted extensively. There is a great variety of depth-damage relationships (with or without basements) in use around the U.S. [18,19]. Therefore, it is widely agreed that the degree of fatality and direct economic cost of flooding is proportional to inundation depth. When urban areas are segmented by infrastructure and buildings, a higher inundation depth would be expected. This gives a new and in-depth explanation why flood damage density has been increasing while the inundation area has been decreasing. And it suggests that flood managers should shift their attention from surface imperviousness to the more fundamental issue of urban form design.
7 Sustainability 2012, Two flood inundation cases are now presented to set the framework for the new proposal outlined in the next section. Both occurred in the Niigata prefecture, Japan. The reason for selecting these two cases is that flood hazard appears to be increasing in the region. Although structural measures such as dam construction, dam operation change to increase flood regulating capacity, channel width enlargement and non-structural measures, such as flood hazard mapping and improvement of evacuation systems have been implemented, the region is still at high risk of flooding. On July 13, 2004, heavy rainfall hit the Sanjo city, Niigata prefecture, which resulted in a levee breach in the Ikarashi river. The flood water spread out largely in two directions; the south and the west . The water moving toward the west was stopped by the National Road No. 8 as one can notice from Figure 5. One can also notice that the inundation depths along the National Road No. 8 were about 2 m due to the blockage of water by the road. This flood disaster accounted for nine victims. Figure 5. Distribution of flood inundation depths in the Sanjo city, Japan, 13, July, Road No. 8 1 km Figure 6. Inundated area when the Abuma river breached on July 30, Breach Inundated 250 m River On July 30, 2011, Niigata prefecture was again hit by extreme rainfall, which resulted in a levee breach and overflow of several rivers. One of them is the Aburuma river, which runs through Uonuma city. In the early morning of July 30, a breach occurred in the lower upstream reach of the Aburuma
8 Sustainability 2012, River. The breach was about 50 m long and on the right river bank. As shown in Figure 6, the flood waters coming out of the river channel were confined to a narrow belt zone along the road. The inundation depths were above 1.5 m almost everywhere in the inundated area, according to a water mark survey. Due to high awareness of flood risk that led to quick evacuation, there was no loss of life associated to this flood event. However, 21 houses were severely inundated. Figure 7 shows that the area behind a dike suffered from waterlogging. Figure 7. Photo showing that an area behind dike suffered from waterlogging. The evidence supports the argument that the contrast between the decline of inundation area and increase of flood damage could be partially caused by urban structures that block flood water propagation. Assuming that with a total volume of flood water Q t, flooding area A m, an average inundation depth H m, the coverage of buildings and houses S, and that there are no water enters buildings or houses, then a general relationship between these variables can be written as follows: H m Qt (1) A ( 1 S) The coverage of buildings and houses in the Sanjo city was approximately 30% and the total volume of flood waters coming out of the Ikarashi river on July 13, 2004: m 3 . If the management goal is to keep the depth below 0.5 m, then, the necessary flooding area should be A m 2Q (1 S) km t 2 34 m (2) It is estimated from the flood hazard map of the Sanjo city that the actual flood potential area in the city is 13 km 2. Excluding the building occupancy from the flood potential area, the available space for accommodating inundating water in the Sanjo city is just 9 km 2. Thus, it can be concluded that the capacity of the Sanjo city to live with flood is far from sufficient. Figure 8 shows the hyetographs at a representative gauging station for the two weather events. It is seen clearly that the 2011 event can be characterized as having a multi-peak pattern as compared to the 2004 event. Besides, the rainfall peak was also higher in 2011 than For such an intensified multi-peak weather pattern, upstream dams would lose their capacities in regulating the second peak flow. It implies that a new concept, a new approach must be sought to deal with the evolving trend of flood hazards.
9 Sustainability 2012, Figure 8. Hyetographs of the two events at the Kasabori rainfall gauging station. Rainfall (mm) Rainfall elapse time Rainfall (mm) Rainfall elapse time 4. A New Concept Based on the aforementioned facts, a new concept that is termed as Flood Sharing is proposed here. It is aimed at establishing a new framework to deal with the residual risk in case of extremely large-scale floods. The logic is that wide but shallow inundation is much less harmful than narrow but deep inundation. Because high water depth is life-threatening and the question with paramount importance in flood disaster management is how to avoid or minimize life loss, the philosophy of going for wide but shallow is justifiable although it could affect more people. Mathematically, it is formulated below dah dt dh da Qin or A H Q (3) dt dt where Q in = flow rate from a levee breach; A = inundation area; H = inundation depth. From Equation (3), A can be obtained as da Qin H A dt (4) dh dt The rate of area expansion da/dt is the speed of flood water propagation and dh/dt is the rate of flood water rise. From the viewpoint of safe evacuation, low speed of floodwater propagation and slow increase of depth is preferred. Equation (4) implies that the realization of low speed and slow rise require a larger inundation area. If the inundation area is confined and the maximum possible area is A max, da/dt becomes zero when A = A max. Then, Equation (4) can be rearranged as dh Qin (5) dt Equation (5) suggests that the smaller the area, the higher the rising speed of flood water depth. A key toward the realization of the wide but shallow concept lies in road networks. Roads are basic and indispensible social infrastructures. The construction of roads has been used as a way toward prosperity across the world. However, the construction of roads alters drainage paths in a watershed. In many urbanized areas, roads account for more than 20% of land-use. For example, in the Ota city of A max
10 Sustainability 2012, metropolitan Tokyo, road coverage accounts for 30% of its land. During flood inundation, roads often turned out to be like river channels, resulting in traffic suspension and road damage. On August , Sayo river in Hyogo prefecture of Japan breached and 18 died in this disaster. Among them, 9 persons lost their lives on their way to an evacuation shelter. In light of road damage and consequent difficulties of the disaster relief operation, preventing roads from being flooded has been considered as a high priority by road engineers and the general public as well. On the other hand, relatively high roads may block flood water propagation either intentionally or unintentionally. Therefore, there is an urgent need to evaluate the relationship between road patterns and urban flooding characteristics. The question to address is Does the road accelerate flooding? A further question is Can we use roads in a smart way to alleviate flood disasters? The following case study gives a preliminary answer to these two questions. A river junction is one of the most flood-prone landscapes. A recent example was the flooding at the Junction of the Mississippi and Ohio rivers in In this study, the Shirone district in Niigata city of Japan is chosen as a target area. As shown in Figure 9, it is an area enclosed by the Shinano river and the Naganokuchi river. It is a flat lowland and very vulnerable to flooding. The road network in the district consists of National Roads No.8, No.46, No.460 and Prefectural Road No.146. Looking from the river junction, the road network in this district can be characterized as a combination of radiating type roads and ring type roads. Figure 9. Road network and rivers in the Shirone district. Breaching point High risk zone River Road Road River Road Road For such a geographical setting, numerical simulations of inundation scenarios were performed with the Hybrid Model. In the case of flood water coming out of the Shinano river from the junction, the numerical simulation shows that the combination of radiating roads with ring roads could confine flood waters, resulting in high inundation depths in the narrow area surrounded by roads, as illustrated in Figure 10. If there was another road slightly leaning toward the east, the numerical experiment indicates that this hypothetical road could divert some portion of flood waters to the east of the region where the land-use is mainly farmland (Figure 11).
11 Sustainability 2012, Figure 10. High flood water depths due to confinement by roads. 1 hour after breach 3 hour after breach Figure 11. Diversion of flood water by a road to a less vulnerable area. Road used for diverting 2 hours after breach Paddies In light of the road s dual capability of blocking and re-directing flow, a new type of road, termed as multi-purpose road, is proposed. It would function as a normal road on normal days, but as a flood diversion channel during an emergency. Besides, roads with a flood water diversion function can be designed in a way that flow velocity along roads is under an acceptable level. The construction of multi-purpose roads may become an engine to realize the wide but shallow strategy. Conventionally,
12 Sustainability 2012, storm sewers are constructed to help prevent flooding by diverting rainfall runoff into nearby rivers and creeks. However, the water levels of nearby waterways are often too high during rainfall events to dump flood waters. Therefore, the integration of storm sewers and multi-purpose roads could lead to better crisis handling. Moreover, storm sewers could be also be utilized for flood sharing, which is a subject for further study. Worded differently, we need to use all available infrastructures and resources in an integrated way for flood disaster minimization. In the case of the Sanjo city inundation on July 13, 2004, if the flood waters could have propagated through the National Road No. 8, the inundation depth on the east side of the road would have been significantly reduced. Since the land use on the west side of the National Road No. 8 is mainly farmland with a very small number of scattered houses, the diversion of flood water to that area is justifiable and can be realized by installing a road culvert. The case of the Aburuma river flooding would be characterized by deep water depth (>1.5 m) across the whole inundation area. The situation was life-threatening, particularly to children. Thus, intentionally spreading flood waters toward the west side could be considered as a life-saving measure. By overlapping population data with designated flood hazard maps for watersheds in the Kanto region, a relationship was obtained between the percentages of flood-threatened population and the percentages of inundation area in the Kanto region as shown in Figure 12. With the exception of the Tsurumi river, where the population density is extremely high (>8000/km 2 ), the population in a flood-prone area of a watershed divided by the total population of that watershed increases as a power function of the ratio between the flood-prone area and the total watershed area. It can be seen clearly that the flood-threatened population percentages are 66% and 77% in the watersheds of the Tone river and the Arakawa river, respectively. The Tone river is the largest river in Japan in terms of flow discharge and drainage area. The Arakawa river is the largest river flowing into the Tokyo Bay and also possesses the widest river channel width among Japanese rivers. It can be also noted that in the watershed of the Tone river, the 66% of the flood-threatened population is concentrated in 25% of its watershed. Such an imbalance justifies the consideration of alternative approaches to conventional blocking practice. Ikeuchi et al.  analyzed six scenarios of large-scale flooding in the watershed of the Tone river and showed that the worst scenario is the inundation in a topographically-enclosed area where the potential depth could be as high as 5 m and the potential loss of life might reach 6,200 if evacuation is not appropriately implemented. This may also be viewed as supporting evidence with regard to the importance of controlling inundation depth. Due to land availability, relocation of residents to make sufficient room for flood waters would be too costly and too time-consuming to be practical in large Japanese cities like Tokyo. Instead, living with flood through flood water sharing could be a sustainable solution because flood risk sharing among the present generation could minimize the burden passed to future generations. Land-use by design, such as road manipulation to achieve sharing, is cost effective, both economically and ecologically, and it is also reversible, and thus satisfies the minimum requirement of sustainability. Besides, sharing would involve more stakeholders, which may enhance the fairness of flood management in the future.
13 Sustainability 2012, Figure 12. Relation between percentage of flood-threatened population and the percentage of inundation area in the Kanto region. flood-threatened population/total population y = x R² = Tone River Arakaw a flood-prone area/total watershed area 5. Conclusions The case study and model analysis of this study indicate that in highly-urbanized areas, a new approach to flood disaster management is needed. The old approach, relying on floodwater localization or blockage, now leads to unacceptably high inundation depths in certain areas. Since high water depth is life-threatening and often results in flood damage at high economic cost, a wide but shallow approach that reduces inundation depth and shares the burden of the risk is a new and justifiable strategy for flood risk management. Flood sharing differs from the existing concepts of flood risk reduction, flood risk retention and flood risk transfer. It can be interpreted as a risk dispersion (or advection + diffusion) process. It aims at reducing damage resulting from large urban floods through transporting floodwaters while flattening the risk. The construction of multi-purpose roads is one of the main tactical measures needed for the realization of the flood-sharing concept, and makes it a particularly useful tool to deal with residual risk. Designing and using urban infrastructure in this way allows for adaptive management and reversibility. Another sustainability benefit of the flood-sharing approach is its built-in mechanism for large-scale public participation and more equitable risk management. Acknowledgements Special thanks to three anonymous reviewers for their critical comments and numerous suggestions that significantly improved the quality of the paper. References 1. OFDA/CRED. EM-DAT: International Disaster Database. Available online: (accessed on 1 May 2012). 2. AlertNet. Available online: (accessed on 1 May 2012).
14 Sustainability 2012, Shang, J.; Wilson, J.P. Watershed urbanization and changing flood behavior across the Los Angeles metropolitan region. Nat. Hazards 2009, 48, Dijkman, J.; Klomp, R.; Villars, M. Flood Management Strategies for the Rivers Rhine and Meuse in the Netherlands. In Proceedings of the Conference on Destructive Water: Water- Caused Natural Disaster, their Abatement and Control, Anaheim, CA, USA, June Kisso 79 (in Japanese); Lower Kiso River Management Office: Kuwana, Mie, Japan, Hamaguchi, T.; Kamada, T. Report of Survey on Double-Dikes along Arakawa River; Technical Note of the Public Works Research Institute, No. 2328; Public Works Research Institute: Tsukuba, Japan, Hirao, T. Living with floods (in Japanese). Jpn. Soc. Nat. Disaster Sci. 2000, 19, Loucks, D.P. Sustainability: what does this mean for us and what can we do about it? In Water Resources Planning in a Changing World, Proceedings of the International UNESCO Symposium: Water Resources Planning in a Changing World, Karlsruhe, Germany, June Samuels, P.G. A New Tool for Sustainable Flood Defense Planning An overview of the EUROTAS Research Project. Paper Presented at the European Conference on Advances in Flood Research, PIK, Potsdam, Germany, Van Stokkom, H.T.; Smits, A.J. Flood Defence in The Netherlands: A New Era, a New Approach; Science Press, New York Ltd.: New York, NY, USA, Department for Environment, Food and rural Affairs. Making space for water-taking forward a new Government strategy for flood and coastal erosion risk management in England. Available online: onse1.pdf (accessed on 1 May 2012). 12. Smith, P. Demolition of flood-damaged Iowa City homes begins. Available online: (accessed on 16 September 2009). 13. Huang, G.W.; Isobe, M. A proposal for flood damage reduction in urban area by Water Pathway (in Japanese). Annu. J. Hydraulic Eng. JSCE 2005, 50, Bates, P.D.; de Roo, A.P.J. A simple raster-based model for floodplain inundation. J. Hydrol. 2000, 236, Duiser, J.A. Een Verkennend Onderzoek Naar Methoden ter Bepaling van Inundatieschade bij Doorbraak. TNO Report ref ; TNO: Delft, Netherlands, Waarts, P. Methode Voor de Bepaling van het Aantal Doden als Gevolg van Inundatie; Report TNO B ; TNO: Delft, Netherlands, Jonkman, S.N.; Maaskant, B.; Boyd, E.; Levitan, M. Loss of life caused by the flooding of New Orleans after Hurricane Katrina: Analysis of the relationship between flood characteristics and mortality. Risk Anal. 2009, 29, Davis, S. Guidelines to Estimating Existing and Future Residential Content Values. IWR Report 93-R-7; U.S. Army Corps of Engineers Water Resources Support Center Institute for Water Resources: Fort Belvoir, Virginia, USA, Kiefer, J.C.; Willett, J.S. Analysis of Nonresidential Content Value and Depth-damage Data for Flood Damage Reduction Study; IWR Report 96-R-12; U.S. Army Corps of Engineers Water Resources Support Center Institute for Water Resources: Alexandria, Virginia, USA, May 1996.
15 Sustainability 2012, Huang, G.W. Characterization of flood inundation in Sanjo City, Japan on July 13, J. Hydrodyn. Ser. B 2006, 18, Huang, G.W. Investigation of flood in Ikarashi River due to the Heavy Rainfall in Niigata and Fukushima Region on July 13, 2004 (in Japanese). Adv. River Eng. 2005, 11, Ikeuchi, K.; Ochi, S.; Yasuda, G.; Okamura, J.; Aono, M. Inundation patterns and fatality analysis on large-scale flood. J. Jpn. Soc. Civ. Eng. Ser. B1 2011, 67, by the authors; licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/3.0/).
Flood Risk Management Value of Flood Risk Management Every year floods sweep through communities across the United States taking lives, destroying property, shutting down businesses, harming the environment
Flood Risk Management Value of Flood Risk Management Value to Individuals and Communities Every year floods sweep through communities across the United States taking lives, destroying property, shutting
Discussion about the practicability of implementing flood risk management and urban flood insurance in China Longhua Gao, Xiaoqing Zhou Abstract: This paper explains the flood risk management at first,
Disaster Prevention Measures in Global-Local Context 4 th World Water Forum Dr. Yoshihiko Yamashita CTI Engineering Co., Ltd Association of Japanese Consulting Engineers Outline of Presentation Up-to to-date
Appendix F Benefit-Cost Analysis of Flood Protection Measures Acronyms used in Appendix F: AA B AA C AA D BC BFE EAD FEMA NED O&M PV RED USACE Average Annual Benefits Average Annual Cost Average Annual
Strategy Name: Reduce Existing Potential for Flood Damages LRSW-S3C1. Develop and implement a program to: Minimize flood damages through the use of structural measures. Minimize flood damages through the
Flood Emergency Response Planning: How to Protect Your Business from a Natural Disaster RIC005 Speakers: Tom Chan, CEO, Global Risk Miyamoto Greg Bates, Principal, Global Risk Consultants Learning Objectives
Bolton s Flood Risk Management Strategy www.bolton.gov.uk Public Summary Bolton s Flood Risk Management Strategy Public Summary Introduction Over 5.5 million properties in England and Wales are at risk
Stormwater Control Measures for Tokyo M. Sugai* *Planning Section, Planning and Coordination Division, Bureau of Sewerage, Tokyo Metropolitan Government, 2-8-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo 163-8001
I-70 East Final EIS 5.14 Floodplains and Drainage/Hydrology 5.14 Floodplains and Drainage/Hydrology This section discusses floodplain and drainage/hydrology resources and explains why they are important
Chapter 2 Flash Flood Science A flash flood is generally defined as a rapid onset flood of short duration with a relatively high peak discharge (World Meteorological Organization). The American Meteorological
6.0 Mitigation Strategy Introduction A mitigation strategy provides participating counties and municipalities in the H-GAC planning area with the basis for action. Based on the findings of the Risk Assessment
Suffield Suffield is a rural community located along the Massachusetts border. It encompasses about 42.2 square miles and has a population of about 15,735. Suffield s terrain rises from an elevation of
Flooding Fast Facts What is a flood? Flooding is the unusual presence of water on land to a depth which affects normal activities. Flooding can arise from: Overflowing rivers (river flooding), Heavy rainfall
Environmental Geology Chapter 5 INTRODUCTION to NATURAL HAZARDS Types of Natural Hazards (e.g. Volcanic eruptions, Earthquakes, Floods,Hurricanes,Landslides Natural Disaster - A particular event in which
Nevada Division of Water Planning A. Flood Management in Nevada Introduction Flooding has been a concern for Nevada communities since the first settlers moved to the territory in the mid-1800 s. Fourteen
Chehalis River Basin Flood Damage Reduction 2013-2015 Capital Budget Approved by Legislature in June 2013 1. Design alternatives for large capital flood projects (basinlevel water retention and Interstate
Netherlands Ministry of Infrastructure and Environment Delta Programme Urban Development and Reconstruction Guideline for Stress Testing the Climate Resilience of Urban Areas Extended summary Version 1.0
Natural Disaster Impact on Business and Communities in Taiwan Dr. Chung-Sheng Lee NCDR Chinese Taipei 1 Brief Introduction of NCDR 2 Organizational Chart of NCDR NDPPC: National Disaster Preparation and
ECONOMIC ANALYSIS FLOOD DAMAGE REDUCTION Lower Carmel River Floodplain Restoration and Enhancement Project I. Description of the Project and its Relationship to Other Projects in the Proposal The Lower
The AIR Inland Flood Model for the United States In Spring 2011, heavy rainfall and snowmelt produced massive flooding along the Mississippi River, inundating huge swaths of land across seven states. As
1008 STORM DRAINAGE (3/24/05) 1008.01 PURPOSE To minimize the amount of stormwater runoff resulting from development utilizing nonstructural controls where possible, maintain and improve water quality,
FLOOD HAZARD AND RISK ASSESSMENT OF HOANG LONG RIVER BASIN, VIETNAM VU Thanh Tu 1, Tawatchai TINGSANCHALI 2 1 Water Resources University, Assistant Professor, 175 Tay Son Street, Dong Da District, Hanoi,
CORFU Project Barcelona Case Study Final Workshop 19 th of May 2014 Flood risk assessment through a detailed 1D/2D coupled model Beniamino Russo Aqualogy Urban Drainage Direction Introduction and general
National Disaster Management Institute CONTENTS one Cause of Urban Flood Disaster two Urban Flood Damage Case three Disaster Prevention Measures for Future Urban Flood four NDMI s Measures & Strategy for
Estimating Potential Reduction Flood Benefits of Restored Wetlands Kenneth W. Potter University of Wisconsin Introduction Throughout the summer of 1993 a recurring question was the impact of wetland drainage
4.14 Netherlands The Netherlands is flood prone for about 60% of its surface. 95 so-called dike-rings protect the polders from being flooded from the North Sea, rivers or lakes. The protection level has
Frequently-Asked Questions about Floodplains and Flood Insurance What is a floodplain? The floodplain is any area covered by water during normal water flows, and which could be inundated as a result of
Flood Insurance Repetitive Loss Property When our system of canals, ditches and culverts was built over 20 years ago, it could handle all but the largest tropical storms and hurricanes; since then, urban
Page 1 of 10 EENS 3050 Tulane University Natural Disasters Prof. Stephen A. Nelson Flooding Hazards, Prediction & Human Intervention This page last updated on 19-Oct-2015 Hazards Associated with Flooding
Department of Planning Report for Riverstone and Alex Avenue Precincts Post Exhibition Flooding and Water Cycle Management (incl. Climate Change impact on Flooding) May 2010 Contents 1. Background 1 1.1
Swannanoa River Flood Risk Management Study Measures Evaluated to Reduce Future Flood Damages City of Asheville U.S. Army Corps of Engineers Flooding History Part of the 132 square mile Swannanoa River
Risk Analysis, Vol. 28, No. 5, 2008 DOI: 10.1111/j.1539-6924.2008.01103.x Flood Risk Assessment in the Netherlands: A Case Study for Dike Ring South Holland Sebastiaan N. Jonkman, 1,2 Matthijs Kok, 1,3
KITTITAS COUNTY DEPARTMENT OF PUBLIC WORKS Kirk Holmes, Director What is a Flood Control Zone District (FCZD)? A Kittitas County Flood Control Zone District (FCZD) would be a special-purpose government
Introduction Welcome to the Indian Creek Conservation Reserve Program (CRP) visualization tool. This tool was developed by the University of Iowa - Institute for Hydroscience and Research (IIHR) as part
A DATABASE OF HISTORICAL FLOOD EVENTS IN THE NETHERLANDS Martine Jak 1 and Matthijs Kok 2 1 Department of Transport, Public works and Water Management Road and Hydraulic Engineering Division P.O. Box 5044
Origins and causes of river basin sediment degradation and available remediation and mitigation options Feedback from the Riskbase workshop Corinne Merly 1, Olivier Cerdan 1, Laurence Gourcy 1 Emmanuelle
Objective 4: Enhanced community education, flood awareness and preparedness Understanding the extent and full impacts of flooding is essential for planning for potential future pressures on the drainage
2D Modeling of Urban Flood Vulnerable Areas Sameer Dhalla, P.Eng. Dilnesaw Chekol, Ph.D. A.D. Latornell Conservation Symposium November 22, 2013 Outline 1. Toronto and Region 2. Evolution of Flood Management
FLOOD PROTECTION AND ECOSYSTEM SERVICES IN THE CHEHALIS RIVER BASIN May 2010 Prepared by for the Execubve Summary The Chehalis Basin experienced catastrophic flooding in 2007 and 2009. In response, the
5.0 OVERVIEW OF FLOOD DAMAGE REDUCTION MEASURES Flood damage reduction consists of two basic techniques structural and non-structural. Structural methods modify the flood and take the flood away from people
Regulatory Alternatives to Address Stormwater Management and Flooding in the Marlboro Street Study Area Alternative 1: Amend Existing Local Regulations This proposed alternative provides an incremental
Page 1 of 7 Post-Flood Assessment CHAPTER 4 AGENCY COORDINATION Agency coordination is an essential element for the operation of the flood management systems in the Central Valley. Due to the nature of
Best Practice of Flood Hazard Map in Japan 1. Hazard map in Japan There are about 1,500 municipalities in Japan, which need to prepare flood hazard map. 510 municipalities have already made and disclosed
Paper 3-4-3 BEST PRACTICE GUIDELINES FOR FLOOD RISK ASSESSMENT IN THE LOWER MEKONG RIVER BASIN GERT SLUIMER 1, HENK OGINK 2, FERDINAND DIERMANSE 2, FRANK KEUKELAAR 1, BAS JONKMAN 1, TRAN KIM THANH 3 AND
LARS 2007 Catchment and Lake Research Flood Forecasting and Early Warning System (FFEWS) an Alternative Technology for Flood Management System and Damage Reduction in Ethiopia: A Concept Note Semu Ayalew
Master Plan on Water Resource Management Strategic Committee for Water Resource Management Office of the Strategic Committee for Water Resource Management Office of the National Economic and Social Development
Comprehensive Flood Control Measures Tokyo Metropolitan Torrential Rain Measures Basic Policy Recently, local torrential rains occur frequently in part of the Tokyo metropolitan area. The extensive flood
The City of Fort Lauderdale participates in the National Flood Insurance Program (NFIP) so that residents can obtain flood insurance to cover their property against loss from flood damage. Participation
Flood Damage Statistics in Japan - What is required for mainstreaming DM? 30 September 2013 Yusuke AMANO Director, International Affairs Office Water and Disaster Management Bureau Ministry of Land, Infrastructure,
Flood Damage Assessment in Taipei City, Taiwan Ming-Hsi Hsu 1, Meng-Yuan Tsai, Yi-Chieh Lin 3, Albert S. Chen 4, Michael J. Hammond 5, Slobodan Djordjević 6 & David Butler 7 1 National Taiwan University,
CITY UTILITIES DESIGN STANDARDS MANUAL Book 2 (SW) SW9 June 2015 SW9.01 Purpose This Chapter provides information for the design of open channels for the conveyance of stormwater in the City of Fort Wayne.
March 10, 2014 Submitted electronically via http://www.nyc.gov Mayor s Office of Long Term Planning and Sustainability c/o Flood Map Comments 253 Broadway, 10th Floor New York, NY 10007 Federal Emergency
Managing sewer flood risk J. Ryu 1 *, D. Butler 2 1 Environmental and Water Resource Engineering, Department of Civil and Environmental Engineering, Imperial College, London, SW7 2AZ, UK 2 Centre for Water
EXECUTIVE SUMMARY The Municipality of Anchorage (MOA) is vulnerable to a wide range of natural, technological, and human/societal hazards including earthquakes, avalanches, and hazardous material accidents.
Sweden Mission from Skane The Dutch Delta Approach Future proof flood risk management in the Netherlands Martien Beek Special advisor to Delta Program Commissioner 18 September 2013 1 The Netherlands exposure
NYSDEC General Comments. The contains language that complies with the floodplain management requirements of the National Flood Insurance Program (NFIP) contained in federal regulations 44 CFR 60.3 through
Background/Introduction RISK ANALYSIS MODULE 3, CASE STUDY 2 Flood Damage Potential at European Scale By Dr. Peter Burek There is good reason to be concerned about the growth of flood losses in Europe.
North San Jose Neighborhoods Planning Taskforce Key Topics Water Supply Flooding Related Topics Storm Water Storm Sewer Sanitary Sewer Water Conservation Treatment Plant Water Background Responsible Agencies
Assessment of flood risks in polders along the Dutch lakes F. den Heijer* & A.P. de LoofP WL\delft hydraulics ^Ministry of Transport, Public Works and Water Management, Directorate General of Public Works
Chapter 6: Mitigation Strategies This section of the Plan describes the most challenging part of any such planning effort the development of a Mitigation Strategy. It is a process of: 1. Setting mitigation
Flood Mitigation in the NYC West-of-Hudson Watershed A guide to Programs, Agencies and Funding Sources for Municipalities and Property Owners In recent years, multiple flood events in the New York City
06 PLANNING FOR POST-DISASTER RECOVERY BRIEFING PAPERS FLOOD INSURANCE AND DESIGN REQUIREMENTS Flood losses are increasing nationwide. A community may take more than a decade to fully recover from a flood,
FLOOD RISK RECENT TRENDS AND POLICY RESPONSES DEVELOPING WESTMINSTER S LOCAL PLAN Booklet No. 2 LDF Consultation - CMP Revision November 2013 INTRODUCTION CLLR ROBERT DAVIS Westminster is at risk of flooding
1 Introduction 1.1 Key objective The aim of this study is to identify and assess possible options for improving the quality of the river channel and habitats in the River South Esk catchment whilst helping
Flood damage assessment and estimation of flood resilience indexes Barcelona case study Marc Velasco CETaqua Workshop CORFU Barcelona Flood resilience in urban areas the CORFU project Cornellà de Llobregat,
US Army Corps of Engineers Hydrologic Engineering Center Methods for Determination of Safe Yield and Compensation Water from Storage Reservoirs October 1966 Approved for Public Release. Distribution Unlimited.
SUFFOLK COASTAL DISTRICT COUNCIL DOMESTIC FLOOD PROTECTION POLICY 1. Introduction 1.1 The Council recognises the threat to local communities from flooding following severe weather events and as a result
Community Preparedness for Flood Resiliency Nina Peek, AICP New York Planning Federation Board of Directors Senior Technical Director AKRF, Inc. Focus of Today s Presentation Why should communities invest
Vermont Economic Resiliency Initiative (VERI) Community Forum Barre City & Barre Town MEETING NOTES April 16, 2015 6:00 8:00 PM VERI Project Overview With funding from the US Economic Development Administration
Chapter 4: After the Disaster How the NFIP Works Who needs flood insurance? Everyone. And everyone in a participating community of the National Flood Insurance Program (NFIP) can buy flood insurance. More
Hydrol. Earth Syst. Sci. Discuss., 5, C2756 C2764, 2010 www.hydrol-earth-syst-sci-discuss.net/5/c2756/2010/ Author(s) 2010. This work is distributed under the Creative Commons Attribute 3.0 License. Hydrology
CASS COUNTY COMMISSION POLICY MANUAL 38.07 SUBJECT: ORDINANCE #1998-2 (FLOOD DAMAGE PREVENTION) ADOPTED DATE: FEBRUARY 2, 1998 PAGE 1 OF 9 NORTH DAKOTA COUNTY OF CASS ORDINANCE #1998-2 Be it ordained and
Floodplain 8-Step Process in accordance with Executive Order 11988: Floodplain Management New Jersey Department of Environmental Protection U.S. Department of Housing and Urban Development Community Development
INTRODUCTION As communities begin to recover from the devastating effects of Hurricane Sandy, it is important to recognize lessons learned and to employ mitigation actions that ensure structures are rebuilt
12 th Meeting of the Conference of the Parties to the Convention on Wetlands (Ramsar, Iran, 1971) Punta del Este, Uruguay, 1-9 June 2015 Resolution XII.13 Wetlands and disaster risk reduction 1. RECALLING
13 UNIVERSITIES COUNCIL ON WATER RESOURCES ISSUE 130, PAGES 13-19, MARCH 2005 Overview of Flood Damages Prevented by U.S. Army Corps of Engineers Flood Control Reduction Programs and Activities James J.
United States Office of Water EPA 916-F-01-032 Environmental Protection (4606) July 2001 Agency Source Water Protection Practices Bulletin Managing Sanitary Sewer Overflows and Combined Sewer Overflows
ACE GLOBAL RISK ENGINEERING INFORMATION BULLETIN BUSINESS FLOOD PLANNING AND MITIGATION GUIDE Introduction The most common cause of flooding is due to established water storage areas (natural and man-made)
LOCAL FLOOD RISK MANAGEMENT STRATEGY Summary Document October 2013 Local Flood Risk Management Strategy Summary 1 Introduction 2 Partner responsibilities 3 What do we know about flooding in the borough?
Climate Change and Sri Lanka Ajith Silva Director/ Policy and Planning Ministry of Environment and Natural Resources Sri Lanka Asia Total Area: 65610 Km Land Area : 62705 Km Inland water : 2905 Km 2 Coastal
USA - EVOLUTION OF POLICY ON FLOODPLAIN MANAGEMENT CASE #86 This case describes integrated floodplain strategies in the US, involving the participation of three levels of government and the private sector.
Click here to access definitions SECTION 12 FLOODPLAIN LANDS 12.1 INTERPRETATION In addition to the terms defined in this By-law, the following terms shall have the corresponding meanings for the purposes
American Recovery and Reinvestment Act (ARRA) Emergency Watershed Protection Program Floodplain Easements Rhode Island Natural Resources Conservation Service Rhode Island NRCS received approximately $2.4
Tropical Storm Allison June 13, 2003, 2:41PM Two years after Allison, Houston has reached a watershed moment By KEVIN SHANLEY Houston is exploding with growth. But city building can be a messy business,
FINAL TECHNICAL MEMORANDUM AWD-00002 FLOWS THROUGH FLOOD DAMAGE REDUCTION AREA July 16, 2012 Table of Contents TABLE OF CONTENTS Table of Contents... 1 Executive Summary... 2 1 Objective... 4 2 Study Approach...
4 th International Symposium on Flood Defence: Managing Flood Risk, Reliability and Vulnerability Toronto, Ontario, Canada, May 6-8, 2008 LOSS OF LIFE CAUSED BY THE FLOODING OF NEW ORLEANS AFTER HURRICANE
FLOOD DAMAGE ASSESSMENT IN THE MEKONG DELTA, VIETNAM ASHIM DAS GUPTA Water Engineering and Management, School of Civil Engineering Asian Institute of Technology, P. O. Box 4, Klongluang Pathumthani 12120,
Melbourne Water Flood Risk Assessment: How flood impacts are assessed in the Port Phillip and Westernport region INTRODUCTION Melbourne Water is the regional drainage and floodplain management authority
Rural Flooding: The Potential Role of Forestry Nadeem Shah, Tom Nisbet, & Huw Thomas Centre for Forestry and Climate Change Structure Background Woodland and Flood Alleviation The Theory. Studies on Woodland