6fd0120f-d465-11e4-abee-f0def148f590
eng
utf8
dataset
Environment Agency
metadata@environment-agency.gov.uk
pointOfContact
2021-04-26
Gemini
2.2
http://www.opengis.net/def/crs/EPSG/0/27700
Source Protection Zones [Merged]
SPZs
source_protection_zones_50k
SOURCE_PROTECTION_ZONES_50K
1990-01-01
creation
2021-03-24
revision
DSTR04808
6fd0120f-d465-11e4-abee-f0def148f590
Source Protection Zones [Merged] have been created as public facing outlines where common boundaries and overlaps (based on zone number) have been removed. Source Protection Zones (SPZs) are defined around large and public potable groundwater abstraction sites. The purpose of SPZs is to provide additional protection to safeguard drinking water quality through constraining the proximity of an activity that may impact upon a drinking water abstraction. This is part of an initial screening process in assessing impacts to groundwater resources. Zones around location sites are defined by groundwater travel time to an abstraction. This is determined through applying Environment Agency groundwater flow models run at the location of abstractions, inputting parameters such as flow direction, geology type, rainfall and hydrological boundaries. SPZs provide a visual representation of the increased risks as you get closer to the abstraction.
The following subdivisions are defined within SPZs:
Zone 1: (Inner Protection Zone) - This zone is defined by a travel time of 50-days or less from any point within the zone at, or below, the water table. Additionally, the zone has as a minimum a 50-metre radius. It is based principally on biological decay criteria and is designed to protect against the transmission of toxic chemicals and water-borne disease.
Zone 2: (Outer Protection Zone) - This zone is defined by the 400-day travel time from a point below the water table. Additionally this zone has a minimum radius of 250 or 500 metres, depending on the size of the abstraction. The travel time is derived from consideration of the minimum time required to provide delay, dilution and attenuation of slowly degrading pollutants.
Zone 3: (Total catchment) - This zone is defined as the total area needed to support the abstraction or discharge from the protected groundwater source.
We’ve extended some zones to include areas where there is protective geology cover, such as clay. This is because activities below the surface, such as deep drilling, could create pathways for pollutants to enter the groundwater. The SPZ maps show them as zones 1c, 2c and 3c.
A further Zone 4, or ‘Zone of Special Interest’ is occasionally defined for some groundwater sources. These zones highlight areas (mainly on non-aquifers) where known local conditions mean that potentially polluting activities could impact on a groundwater source, even though the area is outside the normal catchment of that source. Attribution statement: © Environment Agency copyright and/or database right 2016. All rights reserved.
Environment Agency
DSPcustomerforum@environment-agency.gov.uk
https://support.environment.data.gov.uk/hc/en-gb
Defra Data Services Forum
pointOfContact
irregular
groundwater
water resources management
aquifer
OpenData
theme
GEMET Thesaurus version 2.1
2008-06-13
publication
Open Government Licence
otherRestrictions
license
copyright
There are no public access constraints to this data. Use of this data is subject to the licence identified.
eng
utf8
environment
inlandWaters
true
-6.236
2.072
49.943
55.816
true
http://data.ordnancesurvey.co.uk/doc/country/england
true
http://data.ordnancesurvey.co.uk/doc/country/wales
1990-01-01
Open format | Shapefile (SHP)
Not Applicable
https://environment.data.gov.uk/DefraDataDownload/?mapService=EA/SourceProtectionZonesMerged&Mode=spatial
DSP:ESRI
SourceProtectionZonesMerged_Download
Source Protection Zones (Merged) Download
https://environment.data.gov.uk/spatialdata/source-protection-zones-merged/wms
WMS
SourceProtectionZonesMerged_WMS
Source Protection Zones (Merged) WMS
https://environment.data.gov.uk/spatialdata/source-protection-zones-merged/wfs
WFS
SourceProtectionZonesMerged_WFS
Source Protection Zones (Merged) WFS
https://environment.data.gov.uk/arcgis/rest/services/EA/SourceProtectionZonesMerged/MapServer
WWW:LINK-1.0-http--link
Source_Protection_Zones_Merged_ESRI_REST_Endpoint
Source Protection Zones (Merged) - ESRI REST Endpoint
https://support.environment.data.gov.uk/hc/en-gb
http:
DSP_CUSTOMER_FORUM
Defra Data Services Platform Customer Forum
dataset
Large potable groundwater abstractions are extracted from the National Abstraction Licence Database (NALD) and georeferenced as Source Protection Locations. A groundwater flow model for relevant aquifer is run and classified into zones defined by travel time. Individual Source Protection Zones are merged and dissolved by Zone number stripping out SPZ name. This is for National Security reasons.