WINS Urban Green Infrastructure: Demand for Urban Greenspace - Risk of Pluvial Flooding
This dataset was created for the Welsh Information for Nature Bases Solution or WINS project (previously known as SCCAN) to identify opportunities to carry out land management interventions to increase ecosystem service delivery in a number of key policy areas. What the map shows: The two maps of pluvial flooding show: [A] the risk of standing water accumulating during heavy rainfall on a bright colour ramp from green to purple, and areas at risk of strong overland flow on a darker colour ramp from green to purple, with purple areas being at highest risk in both cases. The separation into standing water and overland flow can help to target intervention – the dark purple area connected to a bright purple area shows where the water flooding the light purple area originates and, hence, where interventions could be located to disrupt flow paths. [B] the demand based on population density and the Welsh index of multiple deprivation on a gradient from light to dark brown, with darker areas having a higher demand. A purple semi-transparent overly indicates the areas at highest risk from the left-hand map to make the maps spatially comparable.
- Identification
- Extent
- Distribution
- Quality
- Keywords
- Spatial Reference System
- Content
- Constraints
- Maintenance
- Metadata
Identification
- Identifier
- NRW_DS121714
- Alternative Title
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- SCCAN Urban Green Infrastructure: Demand for Urban Greenspace - Risk of Pluvial Flooding
- Seilwaith Gwyrdd Trefol: - Galw am Fannau Gwyrdd Trefol - Perygl o Lifogydd Glawol
- Metadata Language
- English
- Lineage
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How the map has been created: In order to create the map, a DSM for the whole of Wales was derived from Nextmap DTM and MasterMap, with MasterMap features being assigned an average height, which was then added onto the DTM. The hydrology of the derived DSM was analysed using SciMap (Durham University, 2016). SciMap was originally designed to model erosion risk throughout the landscape. However, one of the intermediate outputs produced, the network index or connectivity, can be used to approximate urban flood risk, when using a DSM model instead of a DTM model as input. The network index expresses how likely a parcel of land is to pass material (in this case, water) on to another area. The areas with a particularly high network index are at the most risk from pluvial flooding. To separate between standing water and overland flow, slope information was used, with areas on slopes less than 3° being considered as at risk from standing water, whilst areas on steeper slopes are considered to be at risk from overland flow. To determine the demand, population density was considered, with the census data being split into 5 classes using Jenks Natural breaks; the highest two classes are high priority areas, the medium class a low priority area. Additionally, the Welsh Index of Multiple Deprivation was used, in accordance with classes used on wimd.wales.gov.uk. The 2 most deprived classes (rank 1 to 382) are high priority, the medium class (rank 383 to 573) low priority. This dataset was produced for NRW under contract by Environment Systems Ltd.
- Additional Information
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Data gaps and limitations: For urban areas, once the separation of streets and buildings becomes highly relevant, a higher resolution than the 10m pixel sized used for the strategic scale mapping carried out for this project becomes desirable Urban drainage systems are not considered in this mapping; this could lead to some areas modelled to accumulate standing water actually being at lower risk than they are projected to be desirable. Urban drainage systems are not considered in this mapping; this could lead to over-estimation of the standing water risk in some ares.
- Dataset Reference Date (Publication)
- 2018-04-01
Temporal Extent
- Begin date
- 2017-09-01
- End date
- 2018-04-01
- Topic category
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- Planning cadastre
- Society
- Farming
- Biota
- Geoscientific information
- Climatology, meteorology, atmosphere
- Environment
- Elevation
- Imagery base maps earth cover
- Inland waters
Extent
Extent
- Geographic Extent
- Wales (WLS)
))
Distribution
- Format Type and Description
-
-
Geographic Information System
()
- Specification
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ESRI feature Class
-
Geographic Information System
()
Quality
Data quality
- Quality Scope
- Dataset
- Lineage
-
How the map has been created: In order to create the map, a DSM for the whole of Wales was derived from Nextmap DTM and MasterMap, with MasterMap features being assigned an average height, which was then added onto the DTM. The hydrology of the derived DSM was analysed using SciMap (Durham University, 2016). SciMap was originally designed to model erosion risk throughout the landscape. However, one of the intermediate outputs produced, the network index or connectivity, can be used to approximate urban flood risk, when using a DSM model instead of a DTM model as input. The network index expresses how likely a parcel of land is to pass material (in this case, water) on to another area. The areas with a particularly high network index are at the most risk from pluvial flooding. To separate between standing water and overland flow, slope information was used, with areas on slopes less than 3° being considered as at risk from standing water, whilst areas on steeper slopes are considered to be at risk from overland flow. To determine the demand, population density was considered, with the census data being split into 5 classes using Jenks Natural breaks; the highest two classes are high priority areas, the medium class a low priority area. Additionally, the Welsh Index of Multiple Deprivation was used, in accordance with classes used on wimd.wales.gov.uk. The 2 most deprived classes (rank 1 to 382) are high priority, the medium class (rank 383 to 573) low priority. This dataset was produced for NRW under contract by Environment Systems Ltd.
Keywords
Keywords
- Type
- Theme
Citation
- Date (Publication)
- 2008-06-01
Keywords
Keywords
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NRW SMNR Vocabulary
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- Sustainable Management of Natural Resources (SMNR)
- Ecosystem Services (SMNR)
- Type
- Theme
Citation
- Date (Revision)
- 2023-12-27
Spatial Reference System
Content
Content Information
NRW Profile
Custom Elements
Constraints
Constraints
Limitations on Public Access and Use
- Restriction type
- Other restrictions
Access Constraints Directive
- Limitations
- no limitations
Access Constraints Text
- Other constraints
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There are no access restrictions on this data. NRW may release, publish or disseminate it freely.
Use Constraints
- Use constraints type
- Other restrictions
- Other constraints
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© CNC/NRW All rights Reserved. © Office for National Statistics (ONS). Data may be re-used under the terms of the Open Government Licence providing it is done so, acknowledging both the source and copyright of the owners. It is the recipient's responsibility to ensure the data is fit for the intended purpose.
Attribution Statement
- Other constraints
- Open Government Licence (OGL)
Licence
- Other constraints
- Open Government Licence (OGL)
Metadata
Metadata
- File Identifier
- 4f4c4942-4343-5764-6473-313231373134 XML
- Metadata Language
- English
- Parent Identifier
-
WINS Area Statement Opportunity Maps
NRW_DS121668
- Resource type
- Dataset
- Metadata Date
- 2024-05-31T09:18:02.949Z
- Metadata Standard Name
- NRW
- Metadata Standard Version
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1.0