Source Protection Zones (SPZ) Locations
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 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.
A further Zone 4, or ‘Zone of Special Interest’ was previously defined for some groundwater sources. These zones highlighted areas (mainly on non-aquifers) where known local conditions meant that potentially polluting activities could impact on a groundwater source even though the area is outside the normal catchment of that source. In future this zone will be incorporated into one of the other zones (1, 2 or 3), whichever is appropriate in the particular case.
- Identification
- Extent
- Distribution
- Quality
- Keywords
- Spatial Reference System
- Content
- Constraints
- Maintenance
- Metadata
Identification
- Identifier
- NRW_DS121629
- Metadata Language
- English
- Lineage
-
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.
- Dataset Reference Date (Publication)
- 2017-04-01
Temporal Extent
- Begin date
- 2008-01-01
- End date
- 2013-01-01
- Topic category
-
- Inland waters
Extent
Extent
- Geographic Extent
- Wales (WLS)
))
Distribution
- Format Type and Description
-
-
Geographic Information System
(
)
-
Geographic Information System
(
)
Quality
Data quality
- Quality Scope
- Dataset
- Lineage
-
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.
Keywords
Keywords
- Type
- Theme
Citation
- Date (Publication)
- 2008-06-01
Keywords
-
NRW SMNR Keywords
-
- Hydrological Processes (SMNR)
- Sustainable Management of Natural Resources (SMNR)
- Management Areas (SMNR)
- Regulating Services (SMNR)
- Natural Resources (Incl. Features and Processes) (SMNR)
- Cultural Services (SMNR)
- Provisioning Services (SMNR)
- Water Resources (SMNR)
- Ecosystem Services (SMNR)
- Water Quality (SMNR)
- Type
- Theme
Citation
- Date (Publication)
- 2024-06-26
Spatial Reference System
- Code
- Geographic Information System (EPSG:27700)
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
-
Access to this data may be restricted under relevant legislation. NRW may NOT publish or disseminate the data. Requests should be referred to NRW's Access to Information Officer.
Use Constraints
- Use constraints type
- Other restrictions
- Other constraints
-
© CNC/NRW NRW does NOT grant permission to third parties to re-use or disseminate this dataset.
Attribution Statement
- Other constraints
-
Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved.
Licence
- Other constraints
- Not Licenced for Re-use
Metadata
Metadata
- File Identifier
- 4f4c4942-4343-5764-6473-313231363239 XML
- Metadata Language
- English
- Resource type
- Dataset
- Metadata Date
- 2024-10-23T08:48:36.21Z
- Metadata Standard Name
- NRW
- Metadata Standard Version
-
1.0