PLEASE NOTE: This dataset has been retired. It has been superseded by https://environment.data.gov.uk/dataset/04532375-a198-476e-985e-0579a0a11b47.The Flood Map for Planning (Rivers and Sea) includes several layers of information. This dataset covers Flood Zone 2 and should not be used without Flood Zone 3. It is our best estimate of the areas of land at risk of flooding, when the presence of flood defences are ignored and covers land between Zone 3 and the extent of the flooding from rivers or the sea with a 1 in 1000 (0.1%) chance of flooding each year. This dataset also includes those areas defined in Flood Zone 3.This dataset is designed to support flood risk assessments in line with Planning Practice Guidance ; and raise awareness of the likelihood of flooding to encourage people living and working in areas prone to flooding to find out more and take appropriate action.The information provided is largely based on modelled data and is therefore indicative rather than specific. Locations may also be at risk from other sources of flooding, such as high groundwater levels, overland run off from heavy rain, or failure of infrastructure such as sewers and storm drains.The information indicates the flood risk to areas of land and is not sufficiently detailed to show whether an individual property is at risk of flooding, therefore properties may not always face the same chance of flooding as the areas that surround them. This is because we do not hold details about properties and their floor levels. Information on flood depth, speed or volume of flow is not included.NOTE: We have paused quarterly updates of this dataset. Please visit the “Pause to Updates of Flood Risk Maps” announcement on our support pages for further information. We will provide notifications on the Flood Map for Planning website to indicate where we have new flood risk information. Other data related to the Flood Map for Planning will continue to be updated, including data relating to flood history, flood defences, and water storage areas.

The Flood Map for Planning (Rivers and Sea) includes several layers of information. This dataset covers Flood Zone 2 and should not be used without Flood Zone 3. It is our best estimate of the areas of land at risk of flooding, when the presence of flood defences are ignored and covers land between Zone 3 and the extent of the flooding from rivers or the sea with a 1 in 1000 (0.1%) chance of flooding each year. This dataset also includes those areas defined in Flood Zone 3.This dataset is designed to support flood risk assessments in line with Planning Practice Guidance ; and raise awareness of the likelihood of flooding to encourage people living and working in areas prone to flooding to find out more and take appropriate action.The information provided is largely based on modelled data and is therefore indicative rather than specific. Locations may also be at risk from other sources of flooding, such as high groundwater levels, overland run off from heavy rain, or failure of infrastructure such as sewers and storm drains.The information indicates the flood risk to areas of land and is not sufficiently detailed to show whether an individual property is at risk of flooding, therefore properties may not always face the same chance of flooding as the areas that surround them. This is because we do not hold details about properties and their floor levels. Information on flood depth, speed or volume of flow is not included.NOTE: We have paused quarterly updates of this dataset. Please visit the “Pause to Updates of Flood Risk Maps” announcement on our support pages for further information. We will provide notifications on the Flood Map for Planning website to indicate where we have new flood risk information. Other data related to the Flood Map for Planning will continue to be updated, including data relating to flood history, flood defences, and water storage areas.Defra Network WMS server provided by the Environment Agency

The risk of flooding is the predominant natural risk in metropolitan France. Almost half of the municipalities are affected to varying degrees by flooding, as the share of communal areas in flooding areas varies. The risk of flooding is the subject of significant prevention efforts that need to be continued. Controlling urbanisation and reducing the vulnerability of populations in flood zones are among the objectives of the Grenelle of the Environment. Reducing the vulnerability of people in flood zones requires protective measures (e.g.: dikes) and prevention (example: flood risk prevention plans), by reducing the number of people exposed (example: control of urbanisation) and awareness of risk (e.g. preventive information). In some areas, not covered by RIPs, flood zone atlases (AZI) have been established. The AZI is a knowledge document that delimits the flood field of a watercourse on the basis of a so-called hydrogeomorphological method (a geographical approach that studies the natural functioning of a watercourse by analysing the structure of the alluvial plain). These atlases are information material with no direct regulatory scope. Nevertheless, as a flood risk knowledge tool, an AZI can support a refusal of building permits. List of flood risk municipalities classified by river. A municipality may be affected by 3 rivers with flood risk. It may be affected by one or more flood zones and one or more PPRIs, depending on the rivers crossing it. A municipality affected by a PPRI for a river, exits AZI as part of that river.

The risk of flooding is the predominant natural risk in metropolitan France. Almost half of the municipalities are affected to varying degrees by flooding, as the share of communal areas in flooding areas varies. The risk of flooding is the subject of significant prevention efforts that need to be continued. Controlling urbanisation and reducing the vulnerability of populations in flood zones are among the objectives of the Grenelle of the Environment. Reducing the vulnerability of people in flood zones requires protective measures (e.g.: dikes) and prevention (example: flood risk prevention plans), by reducing the number of people exposed (example: control of urbanisation) and awareness of risk (e.g. preventive information). In some areas, not covered by RIPs, flood zone atlases (AZI) have been established. The AZI is a knowledge document that delimits the flood field of a watercourse on the basis of a so-called hydrogeomorphological method (a geographical approach that studies the natural functioning of a watercourse by analysing the structure of the alluvial plain). These atlases are information material with no direct regulatory scope. Nevertheless, as a flood risk knowledge tool, an AZI can support a refusal of building permits. List of flood risk municipalities classified by river. A municipality may be affected by 3 rivers with flood risk. It may be affected by one or more flood zones and one or more PPRIs, depending on the rivers crossing it. A municipality affected by a PPRI for a river, exits AZI as part of that river.

The National Flood Hazard Layer (NFHL) is a geospatial database that contains current effective flood hazard data. FEMA provides the flood hazard data to support the National Flood Insurance Program. You can use the information to better understand your level of flood risk and type of flooding.

The NFHL is made from effective flood maps and Letters of Map Change (LOMC) delivered to communities. NFHL digital data covers over 90 percent of the U.S. population. New and revised data is being added continuously. If you need information for areas not covered by the NFHL data, there may be other FEMA products which provide coverage for those areas.

This dataset has been discontinued. New Flood Zones will be available when the new Flood Map for Planning is published at the end of Summer 2021. Flood Map shows the areas across Wales that could be affected by flooding from rivers or the sea. It also shows flood defences and the areas that benefit from them. Flood Map is designed to raise awareness among the public local authorities and other organisations of the likelihood of flooding and to encourage people living and working in areas prone to flooding to find out more and take appropriate action. The Flood Map includes several layers of information, this layer is: Flood Zone 2, which is NRWs best estimate of the areas of land between Zone 3 and the extent of the flood from rivers or the sea with a 1000 to 1 chance of flooding in any year. It includes those areas defined in Flood Zone 3.

Flood Map shows the areas across Wales that could be affected by flooding from rivers or the sea. It also shows flood defences and the areas that benefit from them. Flood Map is designed to raise awareness among the public local authorities and other organisations of the likelihood of flooding and to encourage people living and working in areas prone to flooding to find out more and take appropriate action. The Flood Map includes several layers of information, this layer is: Flood Zone 2, which is NRWs best estimate of the areas of land between Zone 3 and the extent of the flood from rivers or the sea with a 1000 to 1 chance of flooding in any year. It includes those areas defined in Flood Zone 3.

An online viewable version of this dataset is available via the NRW website.

The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map (DFIRM) databases published by theFederal Emergency Management Agency (FEMA), and any Letters Of Map Revision (LOMRs) that have been issued against those databases since their publication date.All data included in this layer are considered "final" by FEMA. Any preliminary data that appear on maps displayed at community meetings, etc., are not included here.The DFIRM Database is the digital, geospatial version of the flood hazard information (location and attributes for boundaries of flood insurance risk zones) shown on the published paper Flood Insurance Rate Maps (FIRMs). The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal flood risk. The NFHL data are derived from Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data where available. The FISs and FIRMs are published by FEMA. The specifications for the horizontal control of DFIRM data are consistent with those required for mapping at a scale of 1:12,000.The FIRM is the basis for floodplain management, mitigation, and insurance activities for the National Flood Insurance Program (NFIP). Insurance applications include enforcement of the mandatory purchase requirement of the Flood Disaster Protection Act, which "... requires the purchase of flood insurance by property owners who are being assisted by Federal programs or by Federally supervised, regulated or insured agencies or institutions in the acquisition or improvement of land facilities" (Section 2 (b) (4) of the Flood Disaster Protection Act of 1973). In addition to the identification of Special Flood Hazard Areas (SFHAs), the risk zones shown on the FIRMs are the basis for the establishment of premium rates for flood coverage offered through the NFIP. The NFHL data present the flood risk information depicted on the FIRM in a digital format suitable for use in electronic mapping applications. The NFHL database is a subset of the information created for the FIS and serves as a means to archive a portion of the information collected during the FIS.

This EnviroAtlas dataset describes the total counts and percentage of population, land area, and impervious surface in the 1% Annual Chance Flood Hazard area or 0.2% Annual Chance Flood Hazard area of each block group. The flood hazard area is defined by the National Flood Hazard Layer (NFHL) produced by the Federal Emergency Management Agency (FEMA, www.fema.gov). This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

National Flood Hazard Layer (NFHL) for development of the Parcel Inventory dataset for the Housing Element Site Selection (HESS) Pre-Screening Tool.

This NFHL data incorporates all Flood Insurance Rate Map (FIRM) databases published by the Federal Emergency Management Agency (FEMA), and any Letters of Map Revision (LOMRs) that have been issued against those databases since their publication date. It is updated on a monthly basis. The FIRM Database is the digital, geospatial version of the flood hazard information shown on the published paper FIRMs.

The FIRM Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal flood risk. The FIRM Database is derived from Flood Insurance Studies (FISs), previously published FIRMs, flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by FEMA.

In addition to the identification of Special Flood Hazard Areas, the risk zones shown on the FIRMs are the basis for the establishment of premium rates for flood coverage offered through the National Flood Insurance Program. The FIRM Database presents the flood risk information depicted on the FIRM in a digital format suitable for use in electronic mapping applications. The FIRM Database serves to archive the information collected during the Flood Risk Project.

** This flood zone data should not be used for flood insurance purposes, but rather hazard mapping. FIRM data retrieved directly from the FEMA should be used for insurance programs.

Source data, by county, was downloaded from https://msc.fema.gov/portal/advanceSearch.

The Flood Map for Planning (Rivers and Sea) includes several layers of information. This dataset covers Water Storage Areas. It shows those areas that act as a balancing reservoir, storage basin or balancing pond. Their purpose is to attenuate an incoming flood peak to a flow level that can be accepted by the downstream channel. It may also delay the timing of a flood peak so that its volume is discharged over a longer time interval. We have assumed that water storage areas act perfectly and give the same level of protection as when our assessment of the area was carried out. Water storage areas do not completely remove the chance of flooding and can be overtopped or fail in extreme weather conditions.

This dataset is designed to raise awareness of the likelihood of flooding and to encourage people living and working in areas prone to flooding to find out more and take appropriate action.

PLEASE NOTE: this dataset has been retired. It has been superseded by data for Flood Risk Areas: https://environment.data.gov.uk/dataset/f3d63ec5-a21a-49fb-803a-0fa0fb7238b6

Set of shapefiles defining Indicative Flood Risk Areas for local risk. Indicative Flood Risk Areas are provided by the Environment Agency for use by Lead Local Flood Authorities in England in their review during 2017 of Preliminary Flood Risk Assessments and Flood Risk Areas under the Flood Risk Regulations.

The Indicative Flood Risk Areas are primarily based on an aggregated 1km square grid Updated Flood Map for Surface Water (1 in 100 and 1000 annual probability rainfall), informally referred to as the “blue square map”. These are 1km grids across England and consist of the following data layers:

• Surface Water Flood Risk Exposure Grid – 1km square grid that shows places above the flood risk threshold defined, using the 1 in 100 and 1000 annual probability (deep) Flood Map for Surface Water. • Flood risk thresholds used to generate the “blue Squares”: - Number of people > 200 - Number of critical services, including electricity and water > 1 - Number of non-residential properties > 20 • Cluster Maps – are aggregations of 3km by 3km squares that each contain at least 5 touching "blue squares" (i.e. 1km grid squares where one of the thresholds above is exceeded) • Communities at Risk by Lead Local Flooding Authority • People Sensitivity Map by Lead Local Flood Authority.

The Web Service of River Flood Risk Map condition to population T=100 years allows the visualisation and consultation of the data set of the risk maps for the population corresponding to a scenario of average or occasional probability of flooding (100-year return period). The URL of the WMS Service River flood risk map condition to population T=100 years is: https://wms.mapama.gob.es/sig/Agua/Riesgo/RiesgoPob_100/wms.aspx The reference systems offered by this service are: — For geographical coordinates: CRS: 84, EPSG: 4230 (ED50), EPSG: 4326 (WGS 84), EPSG: 4258 (ETRS 89). — For U.T.M coordinates: EPSG:32628 (WGS 84/UTM zone 28N), EPSG:32629 (WGS 84/UTM zone 29N), EPSG:32630 (WGS 84/UTM zone 30N), EPSG:32631 (WGS 84/UTM zone 31N), EPSG:25828 (ETRS 89/UTM zone 28N), EPSG:25829 (ETRS 89/UTM zone 29N), EPSG:25830 (ETRS 89/UTM zone 30N), EPSG:25831 (ETRS 89/UTM zone 31N), EPSG:23028 (ED50/UTM zone 28N), EPSG:23029 (ED50/UTM zone 29N), EPSG:23030 (ED50/UTM zone 30N), EPSG:23031 (ED50/UTM zone 31N).

The flood atlas is part of the State’s approach to flood risk prevention, which is based primarily on informing the population, controlling urbanisation and preserving natural flood expansion areas.

Flood Risk Mapping Studies / Public Information MapsFlooding is a natural process that is a necessary component to the survival and health of many types of ecosystems. The processes and conditions that result in floods are often predictable and usually occur in the same areas, known as floodplains. Unfortunately people are often drawn to inhabit and develop in floodplains as this is usually flat, fertile land. Because of this, floods are one of the most common natural hazards in Newfoundland and Labrador and are often the most costly. Floods can cause considerable damage to property and infrastructure, threaten human lives and cost millions in emergency assistance, clean-up and remediation.Flooding and erosion processes are quite difficult to control and avoid. As such, the best and most cost effective method of minimizing their impact is proper management and planning of known floodplains. Floodplain management usually involves the adoption of land use regulations that limit human exposure to areas prone to flooding events. For more information on the Government’s approach to management of identified flood zones see the Policy for Flood Plain Management.

The flood atlas is part of the State’s approach to flood risk prevention, which is based primarily on informing the population, controlling urbanisation and preserving natural flood expansion areas.

The Flood Map shows the areas across Wales that could be affected by flooding from rivers or the sea. It also shows flood defences and the areas that benefit from them. Flood Map is designed to raise awareness among the public local authorities and other organisations of the likelihood of flooding and to encourage people living and working in areas prone to flooding to find out more and take appropriate action. The Flood Map includes several layers of information, this layer is: Flood Zone 3, which is NRWs best estimate of the areas of land with a 100 to 1 (or greater) chance of flooding each year from rivers or with a 200 to 1 chance (or greater) of flooding each year from the sea.

An online viewable version of this dataset is available via the NRW website.

This EnviroAtlas dataset describes the total counts and percentage of population, land area, and impervious surface in the 1% Annual Chance Flood Hazard area or 0.2% Annual Chance Flood Hazard area of each block group. The flood hazard area is defined by the National Flood Hazard Layer (NFHL) produced by the Federal Emergency Management Agency (FEMA, www.fema.gov). This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

We provide county and state-level flood exposure data, precipitation data, and individual flood maps for each SAR frames to understand flood exposure from the 2019 Flood of Iran at the country level utilizing 673 Sentinel-1 Synthetic Aperture Radar intensity images spanning January to February. A complete description of the method used to obtain probabilistic flood maps and exposure can be found in Sherpa and Shirzaei (2020) but is briefly stated below.

We applied a Bayesian framework to SAR intensity images to calculate the probability of a SAR pixel being flooded (Giustarini et al., 2016; Sherpa et al., 2020), for which a likelihood probability density function was estimated, thereby providing a continuous value between 0 and 1 as a probabilistic flood map. To obtain an estimate of likelihood, an image segmentation scheme using the fast marching algorithm (FMA) is implemented (Sethian, 1999). The percent area exposed to flooding is estimated as the pixel area's multiplication with its flooding probability for pixels located within each county or state divided by the county or state area. The population exposure is calculated by multiplying each county or state's percent area exposure values with their population, assuming a uniform population distribution.

Anyone wishing to use this dataset should cite Sherpa and Shrizaei (2022) and this dataset. Please also contact and contact Sonam Futi Sherpa at sfsherpa@vt.edu for any questions with details of their work, so that we may offer guidance in regard to the best usage of our produced dataset.

Sherpa, S. F., & Shirzaei, M. (2021). Country‐wide flood exposure analysis using Sentinel‐1 synthetic aperture radar data: Case study of 2019 Iran flood. Journal of Flood Risk Management, 15(1), e12770. https://doi.org/10.1111/jfr3.12770

Additional references:

Sherpa, S. F., Shirzaei, M., Ojha, C., Werth, S., & Hostache, R. (2020). Probabilistic mapping of august 2018 flood of Kerala, India, using space-borne synthetic aperture radar. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 13, 896-913. 10.1109/JSTARS.2020.2970337 Giustarini, Laura, Renaud Hostache, Dmitri Kavetski, Marco Chini, Giovanni Corato, Stefan Schlaffer, and Patrick Matgen. "Probabilistic flood mapping using synthetic aperture radar data." IEEE Transactions on Geoscience and Remote Sensing 54, no. 12 (2016): 6958-6969. Sethian, J. A. (1999). Level set methods and fast marching methods: evolving interfaces in computational geometry, fluid mechanics, computer vision, and materials science (Vol. 3). Cambridge university press.

The flood atlas is part of the State’s approach to flood risk prevention, which is based primarily on informing the population, controlling urbanisation and preserving natural flood expansion areas.