Extreme climatic events, such as floods, are becoming increasingly frequent and severe worldwide, including in Pakistan. The Swat River Catchment (SRC), located in the eastern Hindukush region of Pakistan, is highly susceptible to flooding due to its unique geographical and climatic conditions. However, despite the region’s susceptibility, comprehensive flood risk assessments that integrate hazard, vulnerability, and exposure components remain limited. To address this gap, this study assesses flood risk in the SRC using 22 indicators distributed across the three core dimensions of flood risk: hazard, vulnerability, and exposure. Flood hazard was modeled using 11 indicators, broadly categorized into environmental, hydrological, and geographical aspects, while vulnerability was evaluated through socio-economic factors, geographical proximity, and land use characteristics. Exposure was analyzed based on population metrics and critical infrastructure. All data were converted into thematic layers in GIS, systematically weighted using the Analytical Hierarchy Process (AHP) and combined to produce hazard, vulnerability, and exposure maps respectively. These maps were then integrated through a risk equation to generate the final flood risk map. The results reveal that 31% of the study area is in a high flood risk zone, 27% in moderate risk zones, 23% in low risk, and 19% are safe areas. The results were validated using the Area Under the Curve (AUC) technique, yielding a value of 0.92, which indicates high reliability. By presenting the first integrated flood risk assessment for the SRC, this study provides valuable insights into flood-prone areas and risk distribution. These results highlight the urgent need for enhanced flood risk management, especially in urban areas. The developed methodology serves as a valuable tool for disaster management authorities and planners, helping them make risk-informed decisions, allocate resources efficiently, and implement targeted flood mitigation strategies.

[Metadata] Tropical storms, hurricanes, and tsunamis create waves that flood low-lying coastal areas. The National Flood Insurance Program (NFIP) produces flood insurance rate maps (FIRMs) that depict flood risk zones referred to as Special Flood Hazard Areas (SFHA) based modeling 1%-annual-chance flood event also referred to as a 100-year flood. The purpose of the FIRM is twofold: (1) to provide the basis for application of regulatory standards and (2) to provide the basis for insurance rating.

Spatial data set of the territory at significant flood risk (TRI) produced for the GIS Flood Directive aggregated and mapped for reporting purposes for the European Floods Directive.The European Directive 2007/60/EC of 23 October 2007 on the assessment and management of flood risks (OJEU L 288, 06-11-2007, p.27) influences the flood prevention strategy in Europe. It requires the production of a flood risk management plan aimed at reducing the negative consequences of floods on human health, the environment, cultural heritage and economic activity.The objectives and requirements for implementation are laid down in the Law of 12 July 2010 on the National Commitment for the Environment (LENE) and the Decree of 2 March 2011. In this context, the primary objective of flood area and flood risk mapping for IRRs is to contribute, by homogenising and objectifying knowledge of the exposure of issues to floods, to the development of flood risk management plans (FRMPs).This dataset is used to produce the flood area maps and the flood risk map, which respectively represent flood hazards and exposed issues at an appropriate scale. Their objective is to provide quantitative elements allowing a more detailed assessment of the vulnerability of a territory for the three levels of flood probability (strong, medium, low).

Geographic data set produced by the GIS Flood Directive for the territory of Guyana and mapped for reporting purposes for the European Flood Directive. European Directive 2007/60/EC of 23 October 2007 on the assessment and management of flood risks (OJ L 288, 06-11-2007, p. 27) influences the flood prevention strategy in Europe. It requires the production of a flood risk management plan that aims to reduce the negative impact of floods on human health, the environment, cultural heritage and economic activity. The objectives and implementation requirements are laid down in the Law of 12 July 2010 on the National Commitment for the Environment (LENE) and the Decree of 2 March 2011. In this context, the primary objective of flood area and flood risk mapping for IRRs is to contribute, by homogenising and objectifying knowledge of the exposure of issues to floods, to the development of flood risk management plans (FRMPs). This dataset is used to produce the flood area maps and the flood risk map which respectively represent flood hazards and exposed issues at an appropriate scale. Their objective is to provide quantitative elements allowing a more detailed assessment of the vulnerability of a territory for the three levels of flood probability (strong, medium, low).

[Metadata] Tropical storms, hurricanes, and tsunamis create waves that flood low-lying coastal areas. The National Flood Insurance Program (NFIP) produces flood insurance rate maps (FIRMs) that depict flood risk zones referred to as Special Flood Hazard Areas (SFHA) based modeling 1%-annual-chance flood event also referred to as a 100-year flood. The purpose of the FIRM is twofold: (1) to provide the basis for application of regulatory standards and (2) to provide the basis for insurance rating.SFHAs identify areas at risk from infrequent but severe storm-induced wave events and riverine flood events that are based upon historical record. By law (44 Code of Federal Regulations [CFR] 60.3), FEMA can only map flood risk that will be utilized for land use regulation or insurance rating based on historical data, therefore, future conditions with sea level rise and other impacts of climate change are not considered in FIRMs. It is important to note that FEMA can produce Flood Insurance Rate Maps that include future condition floodplains, but these would be considered “awareness” zones and not to be used for regulatory of insurance rating purposes.The State of Hawai‘i 2018 Hazard Mitigation Plan incorporated the results of modeling and an assessment of vulnerability to coastal flooding from storm-induced wave events with sea level rise (Tetra Tech Inc., 2018). The 1% annual-chance-coastal flood zone with sea level rise (1%CFZ) was modeled to estimate coastal flood extents and wave heights for wave-generating events with sea level rise. Modeling was conducted by Sobis Inc. under State of Hawaiʻi Department of Land and Natural Resources Contract No: 64064. The 1%CFZ with 3.2 feet of sea level rise was utilized to assess vulnerability to coastal event-based flooding in mid to - late century.The 1%CFZ with sea level rise would greatly expand the impacts from a 100-year flood event meaning that more coastal land area will be exposed to damaging waves. For example, over 120 critical infrastructure facilities in the City and County of Honolulu, including water, waste, and wastewater systems and communication and energy facilities would be impacted in the 1%CFZ with 3.2 feet of sea level rise (Tetra Tech Inc., 2018). This is double the number of facilities in the SFHA which includes the impacts of riverine flooding.A simplified version of the Wave Height Analysis for Flood Insurance Studies (WHAFIS) extension (FEMA, 2019b) included in Hazus-MH, was used to create the 1% annual chance coastal floodplain. Hazus is a nationally applicable standardized methodology that contains models for estimating potential losses from earthquakes, floods, tsunamis, and hurricanes (FEMA, 2019a). The current 1%-annual-chance stillwater elevations were collected using the most current flood insurance studies (FIS) for each island conducted by FEMA (FEMA, 2004, 2010, 2014, 2015). The FIS calculates the 1%-annual-chance stillwater elevation, wave setup, and wave run-up (called maximum wave crest) at regularly-spaced transects around the islands based on historical data. Modeling for the 1%CFZ used the NOAA 3-meter digital elevation model (DEM) which incorporates LiDAR data sets collected between 2003 and 2007 from NOAA, FEMA, the State of Hawaiʻi Emergency Management Agency, and the USACE (NOAA National Centers for Environmental Information, 2017).Before Hazus was run for future conditions, it was run for the current conditions and compared to the FEMA regulatory floodplain to determine model accuracy. This also helped determine the stillwater elevation for the large gaps between some transects in the FIS. Hazus was run at 0.5-foot stillwater level intervals and the results were compared to the existing Flood Insurance Rate Map (FIRM). The interval of 0.5-feet was chosen as a small enough step to result in a near approximation of the FIRM while not being too impractically narrow to require the testing of dozens of input elevations. The elevation which matched up best was used as the current base flood elevation.Key steps in modeling the projected 1%CFZ with sea level rise include: (1) generating a contiguous (no gaps along the shoreline) and present-day 1%-annual-chance stillwater elevation based on the most recent FIS, (2) elevating the present-day 1%-annual-chance stillwater elevation by adding projected sea level rise heights, and (3) modeling the projected 1%-annual-chance coastal flood with sea level rise in HAZUS using the 1%-annual-chance wave setup and run-up from the FIS. The 1%CFZ extent and depth was generated using the HAZUS 3.2 coastal flood risk assessment model, 3-meter DEM, the FIS for each island, and the IPCC AR5 upper sea level projection for RCP 8.5 scenario for 0.6 feet, 1.0 feet, 2.0 feet, and 3.2 feet of sea level rise above MHHW (IPCC, 2014). The HAZUS output includes the estimated spatial extent of coastal flooding as well as an estimated flood depth map grid for the four sea level rise projections.Using the current floodplain generated with Hazus, the projected 1%-annual-chance stillwater elevation was generated using the four sea level rise projections. This stillwater elevation with sea level rise was used as a basis for modeling. The projected 1%-annual coastal flood with sea level rise was modeled in Hazus using the current 1%-annual-chance wave setup and run-up from the FIS and the projected 1%-annual-chance stillwater elevation with sea level rise. Statewide GIS Program staff extracted individual island layers for ease of downloading. A statewide layer is also available as a REST service, and is available for download from the Statewide GIS geoportal at https://geoportal.hawaii.gov/, or at the Program's legacy download site at https://planning.hawaii.gov/gis/download-gis-data-expanded/#009. For additional information, please refer to summary metadata at https://files.hawaii.gov/dbedt/op/gis/data/coastal_flood_zones_summary.pdf or contact Hawaii Statewide GIS Program, Office of Planning and Sustainable Development, State of Hawaii; PO Box 2359, Honolulu, Hi. 96804; (808) 587-2846; email: gis@hawaii.gov.

Spatial data set produced by the GIS Flood Directive territory at significant risk of flooding (TRI) of Saint-Etienne and mapped for reporting purposes for the European Flood Directive. The European Directive 2007/60/EC of 23 October 2007 on evaluation and flood risk management (OJ L 288, 06-11-2007, p. 27) influences the flood prevention strategy in Europe. It requires the production of a flood risk management plan aimed at reducing the negative consequences of flooding on human health, the environment, cultural heritage and economic activity. The objectives and requirements of achievement are given by the law of 12 July 2010 on the National Commitment for the Environment (LENE) and the Decree of 2 March 2011. Within this framework, the primary objective of the mapping of flood areas and flood risks for IRRs is to contribute, by homogenising and objecting knowledge of the exposure of issues to floods, to the development of Flood Risk Management Plans (IFMPs). This dataset is used to produce flood surface maps and flood risk maps that represent flood hazards and issues on an appropriate scale, respectively. Their objective is to provide quantitative elements to assess the vulnerability of a territory more accurately for the three levels of flood probability (high, medium, low).

Spatial data set produced by the GIS Flood Directive for the territory of Mayotte and mapped for reporting purposes for the European Floods Directive.The European Directive 2007/60/EC of 23 October 2007 on the assessment and management of flood risks (OJ EU L 288, 06-11-2007, p.27) influences the flood prevention strategy in Europe. It requires the production of a flood risk management plan that aims to reduce the negative impact of floods on human health, the environment, cultural heritage and economic activity. The objectives and implementation requirements are laid down in the Law of 12 July 2010 on the National Commitment for the Environment (LENE) and the Decree of 2 March 2011. In this context, the primary objective of flood area and flood risk mapping for IRRs is to contribute, by homogenising and objectifying knowledge of the exposure of issues to floods, to the development of flood risk management plans (FRMPs).This dataset is used to produce the flood area maps and the flood risk map, which respectively represent flood hazards and exposed issues at an appropriate scale. Their objective is to provide quantitative evidence to further assess the vulnerability of a territory for the three levels of flood probability (strong, medium, low). https://data.georisques.fr/id/dataset/80fcc4da-af64-4bd3-8d2c-8deb73d9a9aa

Robust risk assessment requires accurate flood intensity area mapping to allow for the identification of populations and elements at risk. However, available flood maps in West Africa lack spatial variability while global datasets have resolutions too coarse to be relevant for local scale risk assessment. Consequently, local disaster managers are forced to use traditional methods such as watermarks on buildings and media reports to identify flood hazard areas. In this study, remote sensing and Geographic Information System (GIS) techniques were combined with hydrological and statistical models to delineate the spatial limits of flood hazard zones in selected communities in Ghana, Burkina Faso and Benin. The approach involves estimating peak runoff concentrations at different elevations and then applying statistical methods to develop a Flood Hazard Index (FHI). Results show that about half of the study areas fall into high intensity flood zones. Empirical validation using statistical confusion matrix and the principles of Participatory GIS show that flood hazard areas could be mapped at an accuracy ranging from 77% to 81%. This was supported with local expert knowledge which accurately classified 79% of communities deemed to be highly susceptible to flood hazard. The results will assist disaster managers to reduce the risk to flood disasters at the community level where risk outcomes are first materialized.

The tropical cyclonic strong wind and storm surge model use information from 2594 historical tropical cyclones, topography, terrain roughness, and bathymetry. The historical tropical cyclones used in GAR15 cyclone wind and storm surge model are from five different oceanic basins: Northeast Pacific, Northwest Pacific, South Pacific, North Indian, South Indian and North Atlantic and the tracks were obtained from the IBTrACS database (Knapp et al. 2010). This database represents the repository of information associated with tropical cyclones that is the most up to date. Topography was taken from the Shuttle Radar Topography Mission (SRTM) of NASA, which provides terrain elevation grids at a 90 meters resolution, delivered by quadrants over the world. To account for surface roughness, polygons of urban areas worldwide were obtained from the Socioeconomic Data and Applications Centre, SEDAC (CIESIN et al., 2011). This was considered a good proxy of the spatial variation of surface roughness. A digital bathymetry model is employed with a spatial resolution of 30 arc-seconds, taken from the GEBCO_08 (General Bathymetric Chart of the Oceans) Grid Database of the British Oceanographic Data Centre (2009). Bathymetry is the information about the underwater floor of the ocean having direct influence on the formation of the storm surge. More information about the cyclone wind and storm surge hazard can be found in CIMNE et al., 2015a. Hazard analysis was performed using the software CAPRA Team Tropical Cyclones Hazard Modeler (Bernal, 2014). The vulnerability models used in the risk calculation for GAR correlate loss to the wind speed for 3-seconds gusts. For GAR15, the risk was calculated with the CAPRA-GIS platform which is risk modelling tool of the CAPRA suite (www.ecapra.org). The risk assessment was also conducted by CIMNE and Ingeniar to produced AAL and PML values for cyclone risk.

[Metadata] Tropical storms, hurricanes, and tsunamis create waves that flood low-lying coastal areas. The National Flood Insurance Program (NFIP) produces flood insurance rate maps (FIRMs) that depict flood risk zones referred to as Special Flood Hazard Areas (SFHA) based modeling 1%-annual-chance flood event also referred to as a 100-year flood. The purpose of the FIRM is twofold: (1) to provide the basis for application of regulatory standards and (2) to provide the basis for insurance rating.SFHAs identify areas at risk from infrequent but severe storm-induced wave events and riverine flood events that are based upon historical record. By law (44 Code of Federal Regulations [CFR] 60.3), FEMA can only map flood risk that will be utilized for land use regulation or insurance rating based on historical data, therefore, future conditions with sea level rise and other impacts of climate change are not considered in FIRMs. It is important to note that FEMA can produce Flood Insurance Rate Maps that include future condition floodplains, but these would be considered “awareness” zones and not to be used for regulatory of insurance rating purposes.The State of Hawai‘i 2018 Hazard Mitigation Plan incorporated the results of modeling and an assessment of vulnerability to coastal flooding from storm-induced wave events with sea level rise (Tetra Tech Inc., 2018). The 1% annual-chance-coastal flood zone with sea level rise (1%CFZ) was modeled to estimate coastal flood extents and wave heights for wave-generating events with sea level rise. Modeling was conducted by Sobis Inc. under State of Hawaiʻi Department of Land and Natural Resources Contract No: 64064. The 1%CFZ with 3.2 feet of sea level rise was utilized to assess vulnerability to coastal event-based flooding in mid to - late century.The 1%CFZ with sea level rise would greatly expand the impacts from a 100-year flood event meaning that more coastal land area will be exposed to damaging waves. For example, over 120 critical infrastructure facilities in the City and County of Honolulu, including water, waste, and wastewater systems and communication and energy facilities would be impacted in the 1%CFZ with 3.2 feet of sea level rise (Tetra Tech Inc., 2018). This is double the number of facilities in the SFHA which includes the impacts of riverine flooding.A simplified version of the Wave Height Analysis for Flood Insurance Studies (WHAFIS) extension (FEMA, 2019b) included in Hazus-MH, was used to create the 1% annual chance coastal floodplain. Hazus is a nationally applicable standardized methodology that contains models for estimating potential losses from earthquakes, floods, tsunamis, and hurricanes (FEMA, 2019a). The current 1%-annual-chance stillwater elevations were collected using the most current flood insurance studies (FIS) for each island conducted by FEMA (FEMA, 2004, 2010, 2014, 2015). The FIS calculates the 1%-annual-chance stillwater elevation, wave setup, and wave run-up (called maximum wave crest) at regularly-spaced transects around the islands based on historical data. Modeling for the 1%CFZ used the NOAA 3-meter digital elevation model (DEM) which incorporates LiDAR data sets collected between 2003 and 2007 from NOAA, FEMA, the State of Hawaiʻi Emergency Management Agency, and the USACE (NOAA National Centers for Environmental Information, 2017).Before Hazus was run for future conditions, it was run for the current conditions and compared to the FEMA regulatory floodplain to determine model accuracy. This also helped determine the stillwater elevation for the large gaps between some transects in the FIS. Hazus was run at 0.5-foot stillwater level intervals and the results were compared to the existing Flood Insurance Rate Map (FIRM). The interval of 0.5-feet was chosen as a small enough step to result in a near approximation of the FIRM while not being too impractically narrow to require the testing of dozens of input elevations. The elevation which matched up best was used as the current base flood elevation.Key steps in modeling the projected 1%CFZ with sea level rise include: (1) generating a contiguous (no gaps along the shoreline) and present-day 1%-annual-chance stillwater elevation based on the most recent FIS, (2) elevating the present-day 1%-annual-chance stillwater elevation by adding projected sea level rise heights, and (3) modeling the projected 1%-annual-chance coastal flood with sea level rise in HAZUS using the 1%-annual-chance wave setup and run-up from the FIS. The 1%CFZ extent and depth was generated using the HAZUS 3.2 coastal flood risk assessment model, 3-meter DEM, the FIS for each island, and the IPCC AR5 upper sea level projection for RCP 8.5 scenario for 0.6 feet, 1.0 feet, 2.0 feet, and 3.2 feet of sea level rise above MHHW (IPCC, 2014). The HAZUS output includes the estimated spatial extent of coastal flooding as well as an estimated flood depth map grid for the four sea level rise projections.Using the current floodplain generated with Hazus, the projected 1%-annual-chance stillwater elevation was generated using the four sea level rise projections. This stillwater elevation with sea level rise was used as a basis for modeling. The projected 1%-annual coastal flood with sea level rise was modeled in Hazus using the current 1%-annual-chance wave setup and run-up from the FIS and the projected 1%-annual-chance stillwater elevation with sea level rise. Statewide GIS Program staff extracted individual island layers for ease of downloading. A statewide layer is also available as a REST service, and is available for download from the Statewide GIS geoportal at https://geoportal.hawaii.gov/, or at the Program's legacy download site at https://planning.hawaii.gov/gis/download-gis-data-expanded/#009. For additional information, please refer to summary metadata at https://files.hawaii.gov/dbedt/op/gis/data/coastal_flood_zones_summary.pdf or contact Hawaii Statewide GIS Program, Office of Planning and Sustainable Development, State of Hawaii; PO Box 2359, Honolulu, Hi. 96804; (808) 587-2846; email: gis@hawaii.gov.

DamaGIS is a GIS database which aims to collect and assess flood-related damage data at the local scale. What sets this database apart is the type of sources it uses. Indeed, all types of sources are considered such as on-site observations, online media or even social networks. Moreover, the database aims to be filled out in the future by a large number of contributors for the sake of data completeness and accuracy.

The reason for creating this database was the lack of precise damage data available to calibrate and validate flood risk assessment models. To this end, DamaGIS offers highly precise and easily accessible flood-related damage data. A simplified method to easily assess damage severity is also proposed to enable data comparison across time and location.

Since 2011, 729 damage entries caused by 23 flood events in the South of France have been reported within the database. The geodatabase contains two feature classes.

The first feature class is called “EVENT”. It is a shape field containing polygon geometries for geographic features. The EVENT feature class identifies flood events that have caused damage in the South of France since 2011.

The second and main feature class of the structure is the DAMAGE database, which catalogues flood-related damage. It is a shape field containing point geometries for geographic features.

This version of the Database includes 3 different formats to enable using the Database with both QGIS and MAPINFO software.

The IRR flood and flood risk maps were approved on 03 December 2014 by Prefectural Order No 2014337-0002. The geostandard Flood Directive describes the basis of geographical data produced on territories with significant flood risk (TRI) and mapped for reporting purposes for the European Flood Directive. European Directive 2007/60/EC of 23 October 2007 on the assessment and management of flood risks (OJ L 288, 06-11-2007, p. 27) influences the flood prevention strategy in Europe by requiring the production of flood risk management plans for each river basin district. Article 1 of the Flood Directive specifies its objective of establishing a framework for the assessment and management of flood risks, which aims to reduce the negative consequences of flooding on human health, the environment, cultural heritage and economic activity. The objectives and implementation requirements are set out in the Law of 12 July 2010 on the National Commitment for the Environment (LENE) and the Decree of 2 March 2011. In this context, the primary objective of flood and flood risk mapping for TRIs is to contribute, by homogenising and objectivating knowledge of flood exposure, to the drafting of flood risk management plans (WRMs), to the definition of the objectives of the plan and to the development of local strategies by TRI. Thus, the purpose of this geostandard is to: 1. homogenise the production of data used for flooding and flood risk maps, 2. facilitate the implementation of a GIS on each IRR. This Flood Directive GIS should become a living reference for knowledge of hazards and flood risks on these IRRs and will be used to establish flood risk management plans. IRR GIS will be integrated into a common national GIS.

The geostandard Flood Directive describes the basis of geographical data produced on territories with significant flood risk (TRI) and mapped for reporting purposes for the European Flood Directive. European Directive 2007/60/EC of 23 October 2007 on the assessment and management of flood risks (OJ L 288, 06-11-2007, p. 27) influences the flood prevention strategy in Europe by requiring the production of flood risk management plans for each river basin district. Article 1 of the Flood Directive specifies its objective, which is to establish a framework for the assessment and management of flood risks, which aims to reduce the negative consequences of floods on human health, the environment, cultural heritage and economic activity.The objectives and requirements for implementation are laid down by the Law of 12 July 2010 establishing a national commitment for the environment (LENE) and the Decree of 2 March 2011. In this context, the primary objective of flood and flood risk mapping for IRRs is to contribute, by homogenising and objectivating knowledge of flood exposure, to the drafting of flood risk management plans (WRMs), to the definition of the objectives of this plan and to the development of local strategies by TRI. Thus, this geostandard aims to:1. homogenise the production of data used for flood and flood risk maps.2 facilitate the implementation of a GIS on each IRR. This Flood Directive GIS should become a living reference for knowledge of hazards and flood risks on these IRRs and will be used to establish flood risk management plans. IRR GIS will be integrated into a common national GIS. Tables in the lot: — N_TRI_MANS_CARTE_INOND_S_072 — N_TRI_MANS_CARTE_RISQ_S_072 — N_TRI_MANS_COMMUNE_S_072 — N_TRI_MANS_ENJEU_CRISE_L_072 — N_TRI_MANS_ENJEU_CRISE_P_072 — N_TRI_MANS_ENJEU_DCE_S_072 — N_TRI_MANS_ENJEU_ECO_S_072 — N_TRI_MANS_ENJEU_IPPC_P_072 — N_TRI_MANS_ENJEU_PATRIM_P_072 — N_TRI_MANS_ENJEU_PATRIM_S_072 — N_TRI_MANS_ENJEU_STEU_P_072 — N_TRI_MANS_INONDABLE_S_072 — N_TRI_MANS_ISO_COTE_L_072 — N_TRI_MANS_ISO_HT_S_072 — N_TRI_MANS_OUV_PROTEC_L_072 — N_TRI_MANS_QUARTIER_S_072 — N_TRI_MANS_TRI_S_072

Riverine flood hazard: The GAR 15 global flood hazard assessment uses a probabilistic approach for modelling riverine flood major river basins around the globe. The main steps in this methodology consists of: Compiling a global database of stream-flow data, merging different sources gathering more than 8000 stations over the globe. Calculating river discharge quantiles at various river sections. In another word calculating the range of possible discharges from very low to the maximum possible at series of locations along the river. The time span in the global stream-flow dataset is long enough to allow extreme value analysis. Where time series of flow discharges were too short or incomplete, they were improved with proxy data from stations located in the same “homogeneous region.” Homogeneous regions were calculated taking into account information such as climatic zones, hydrological characteristics of the catchments, and statistical parameters of the streamflow data. The calculated discharge quantiles were introduced to river sections, whose geometries were derived from topographic data (SRTM), and used with a simplified approach (based on Manning’s equation) to model water levels downstream. This procedure allowed for the determination of the reference Flood hazard maps for different return periods (6 are shown in the global study: T= 25, 50, 100, 200, 500, 1000 years). The hazard maps are developed at 1kmx1km resolution. Such maps have been validated against satellite flood footprints from different sources (DFO archive, UNOSAT flood portal) and well performed especially for the big events For smaller events (lower return periods), the GAR Flood hazard maps tend to overestimate with respect to similar maps produced locally (hazard maps where available for some countries and were used as benchmark). The main issue being that, due to the resolution, the GAR flood maps do not take into account flood defences that are normally present to preserve the value exposed to floods. This can influence strongly the results of the risk calculations and especially of the economic parameters. In order to tackle this problem some post processing of the maps has been performed, based on the assumption that flood defences tend to be higher where the exposed value is high and then suddenly drop as this value reduces. The flood hazard assessment was conducted by CIMA Foundation and UNEP-GRID. The flood maps with associated probability of occurrence, is then used by CIMNE as input to the computation of the flood risk for GAR15 as Average Annual Loss values in each country. Hazard maps for six main return periods are developed and available, and probable maximum loss calculations are underway which will be available within few months of GAR15 launch. For GAR15, the risk was calculated with the CAPRA-GIS platform which is risk modelling tool of the CAPRA suite (www.ecapra.org). More information about the flood hazard assessment can be found in the background paper (CIMA Foundation, 2015).

Geographic data set produced by the GIS Flood Directive for the territory of Guadeloupe and mapped for reporting purposes for the European Flood Directive. European Directive 2007/60/EC of 23 October 2007 on the assessment and management of flood risks (OJ L 288, 06-11-2007, p. 27) influences the flood prevention strategy in Europe. It requires the production of a flood risk management plan that aims to reduce the negative impact of floods on human health, the environment, cultural heritage and economic activity. The objectives and implementation requirements are laid down in the Law of 12 July 2010 on the National Commitment for the Environment (LENE) and the Decree of 2 March 2011. In this context, the primary objective of flood area and flood risk mapping for IRRs is to contribute, by homogenising and objectifying knowledge of the exposure of issues to floods, to the development of flood risk management plans (FRMPs). This dataset is used to produce the flood area maps and the flood risk map which respectively represent flood hazards and exposed issues at an appropriate scale. Their objective is to provide quantitative elements allowing a more detailed assessment of the vulnerability of a territory for the three levels of flood probability (strong, medium, low).

The Geostandard Flood Directive describes the basis of geographic data produced on the 120 territories at significant risk of flooding (TRI) and mapped for reporting purposes for the European Flood Directive. European Directive 2007/60/EC of 23 October 2007 on the assessment and management of flood risks (OJ 2007 L 288, 06-11-2007, p. 27) influences the flood prevention strategy in Europe by requiring the production of flood risk management plans on each river basin district. Article 1 of the Floods Directive sets out its objective of establishing a framework for the assessment and management of flood risks, which aims to reduce the negative consequences of flooding on human health, the environment, cultural heritage and economic activity. The objectives and requirements for achievement are given by the Law of 12 July 2010 on the National Commitment for the Environment (LENE) and the Decree of 2 March 2011. Within this framework, the primary objective of the mapping of flood areas and flood risks for IRRs is to contribute, by homogenising and objecting knowledge of the exposure of issues to floods, to the drafting of flood risk management plans (FRPs), to the definition of the objectives of this plan and to the development of local strategies by TRI. Thus, this Geostandard aims to: 1. homogenise the production of data used for flood area and flood hazard maps, 2. facilitate the implementation of GIS on each IRR. This GIS Flood Directive should become a living reference for knowledge of the hazards and risks of flooding on these IRRs and will be used to establish flood risk management plans. IRR SGIs will be integrated into a national common GIS.

The IRR flood and flood risk maps were approved on 03 December 2014 by Prefectural Order No 2014337-0002. The geostandard Flood Directive describes the basis of geographical data produced on territories with significant flood risk (TRI) and mapped for reporting purposes for the European Flood Directive. European Directive 2007/60/EC of 23 October 2007 on the assessment and management of flood risks (OJ L 288, 06-11-2007, p. 27) influences the flood prevention strategy in Europe by requiring the production of flood risk management plans for each river basin district. Article 1 of the Flood Directive specifies its objective of establishing a framework for the assessment and management of flood risks, which aims to reduce the negative consequences of flooding on human health, the environment, cultural heritage and economic activity. The objectives and implementation requirements are set out in the Law of 12 July 2010 on the National Commitment for the Environment (LENE) and the Decree of 2 March 2011. In this context, the primary objective of flood and flood risk mapping for TRIs is to contribute, by homogenising and objectivating knowledge of flood exposure, to the drafting of flood risk management plans (WRMs), to the definition of the objectives of the plan and to the development of local strategies by TRI. Thus, the purpose of this geostandard is to: 1. homogenise the production of data used for flooding and flood risk maps, 2. facilitate the implementation of a GIS on each IRR. This Flood Directive GIS should become a living reference for knowledge of hazards and flood risks on these IRRs and will be used to establish flood risk management plans. IRR GIS will be integrated into a common national GIS.