Fluvial Audits of Welsh River Systems

Geomorphological assessments that utilised historical information, contemporary field survey and scientific literature resources, have been undertaken for various Welsh river systems of high conservation importance including the Usk, Wye, Dee and Tywi.

The purpose of these fluvial audits it to record the morphological features and to identify, and understand the geomorphological processes that influence and control the channel activity, and the morphological quality of the river systems.

Specific aims of each project include (but are not limited to):

- Developing an understanding of the dynamic geomorphology of the key Welsh river systems.

- Examining changes to the channel planform over time using historical maps and aerial photographs.

- Investigating channel and catchment changes using historical records and consultation with Environment Agency (EA) staff, and to develop a time chart which identifies Potentially Destabilising Phenomena (PDP's).

- Identifying the major geomorphological features and processes occurring by undertaking a field survey of present erosion, deposition, bank protection, flow types and sediment sources.

- Identifying the key areas of channel instability (geomorphological activity) and determine the possible factors affecting this instability, in particular those contributing to any severe bank erosion evident.

- Determining the presence and absence of geomorphological features associated with the SAC species habitats.

Identifier: NRW_DS101833

Alternative Title

Metadata Language: English

Lineage: A standard field methodology was used for the, fluvial audit, which consists of:

i) a desk study to collate historical data sources which record changes in the catchment, both natural and anthropogenic, which may have disturbed the fluvial system (discharge or sediment supply), and had direct implications on the channel morphology (change in channel planform, long profile and cross sectional geometry)

ii) a contemporary field survey which integrated the key components of both a Detailed Catchment Baseline Survey (DCBS) and Fluvial Audit (FA), and emphasised assessment of the controls and extent of erosion and deposition along the channel.

The surveys have investigated the channel morphology, in particular the presence of bank erosion on a reach-by-reach basis and artificial influences on the channel. This, together with historic analysis enables an assessment of the stability or dynamics of the river system over time and whether it is adjusted to the prevailing flow processes and sediment dynamics, or unstable and actively adjusting (eroding).

The surveys have also related the presence or absence of morphological features to the condition parameters that are identified as habitat preferences for the Special Areas of Conservation species.

Additional Information: See the separate metadata entries:

Fluvial Audit of the Upper Usk Tributaries (URI: 110182)

Fluvial Audit of the River Dee (110183)

Fluvial Audit of the Afon Tywi (URI: 111562)

Fluvial audit of the River Wye and tributaries (URI: 111860).

Dataset Reference Date (Publication): 2007-07-31

Temporal Extent

Begin date: 1953-12-31

End date: 2007-07-31

Topic category

Inland waters

Owner

Natural Resources Wales (NRW) -

Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales

http://naturalresources.wales/?lang=en

Originator

GeoData Institute. University of Southampton -

GeoData Institute. University of Southampton, University of Southampton, Southampton , SO17 1BJ

www.geodata.soton.ac.uk

Originator

Gifford and partners Ltd -

Not Provided

Originator

Geography and Environmental Management Research Unit, University of Gloucestershire -

Not Provided

Extent

Geographic Extent: Wales (WLS)

Distribution

Format Type and Description

Documents ( Unknown )

Specification

Report in PDF (some sections of report available in Word).
Image ( Unknown )

Specification

JPEG field photos. Images are hyperlinked in relevant GIS layer.
Geographic Information System ( Unknown )

Specification

GIS products e.g. bank status, bar area tree cover etc - MapInfo.Tab. Field Data in Map Info Format. Access Data in Map Info Format. Geological Data in Map Info Format. Historical information in Map Info Format. River, Canal and Reservoir locations in Map Info Format. Hotlinked Photographs in Map Info Format. MapInfo tables- Species data, Bank protection, Gravel extraction, Channel line Fluvial audit of the River Wye and tributaries. Bank Protection, Coarse Woody Debris, Embankments, Erosion, Geomorphological Reaches, Historical Changes, Habitat Sustainability Analysis (HAS), Photos, Sediment Sources (linear feature), Sediment Sources (point feature), Sediment Storage (Area), Structures and Terraces.
Delimited ( Unknown )

Specification

Location of Files .csv format. Habitat Suitability Analysis spreadsheets: HAS.XLS
Database ( Unknown )

Specification

Field survey data - MS Access Fluvial Audit of the River Dee. DeeData Access Database,

Data quality

Quality Scope: Dataset

Conformity: Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services
Explanation: This dataset has not been assessed for conformance to the referenced INSPIRE regulation.
Degree: false

Lineage: A standard field methodology was used for the, fluvial audit, which consists of:

i) a desk study to collate historical data sources which record changes in the catchment, both natural and anthropogenic, which may have disturbed the fluvial system (discharge or sediment supply), and had direct implications on the channel morphology (change in channel planform, long profile and cross sectional geometry)

ii) a contemporary field survey which integrated the key components of both a Detailed Catchment Baseline Survey (DCBS) and Fluvial Audit (FA), and emphasised assessment of the controls and extent of erosion and deposition along the channel.

The surveys have investigated the channel morphology, in particular the presence of bank erosion on a reach-by-reach basis and artificial influences on the channel. This, together with historic analysis enables an assessment of the stability or dynamics of the river system over time and whether it is adjusted to the prevailing flow processes and sediment dynamics, or unstable and actively adjusting (eroding).

The surveys have also related the presence or absence of morphological features to the condition parameters that are identified as habitat preferences for the Special Areas of Conservation species.

Keywords

GEMET - INSPIRE themes, version 1.0

Hydrography

Type: Theme

Citation

Date (Publication): 2008-06-01

Code: geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme

Keywords

NRW Thesaurus

fluvial geomorphology
river Tywi (afon Tywi)
marine and freshwater inventory
River Usk
rivers (see also specific river names)
fluvial processes
fluvial
River Wye (Afon Gwy)
river Dee (afon Dyfrdwy)

Type: Theme

Citation

Date (Publication): 2026-08-27

Code: geonetwork.thesaurus.local.theme.converted_nrw-keywords

Code: British National Grid (EPSG::27700)

Content Information

NRW Profile

Custom Elements

NRW Related Title: A fluvial audit of the Afon Tywi : Volume 1 : technical report

NRW Related Title: A fluvial audit of the Afon Tywi : Volume 2 : map volume

NRW Related Title: A fluvial audit of the Afon Tywi : Volume 2 : map volume (addendum revised figure 16d)

NRW Related Title: A fluvial audit of the Afon Tywi : Volume 3 : summary report

NRW Related Title: Fluvial audit of the River Dee

NRW Related Title: Fluvial audit of the upper Usk tributaries

Constraints

Limitations on Public Access and Use

Restriction type: Other restrictions

Access Constraints Directive

Limitations: no limitations

Access Constraints Text

Other constraints: There are partial access restrictions to this data. Please refer to individual metadata entries in the 'contains' field for specific restrictions: Fluvial Audit of the Upper Usk Tributaries (URI: 110182) Fluvial Audit of the River Dee (URI: 110183) Fluvial Audit of the Afon Tywi (URI: 111562) Fluvial audit of the River Wye and tributaries (URI: 111860)

Use Constraints

Use constraints type: Other restrictions

Other constraints: There are use restrictions on this data. Please refer to individual metadata entries in the 'contains' field for specific restrictions: Fluvial Audit of the Upper Usk Tributaries (URI: 110182) Fluvial Audit of the River Dee (110183) Fluvial Audit of the Afon Tywi (URI: 111562) Fluvial audit of the River Wye and tributaries (URI: 111860)

Metadata

File Identifier: 4f4c4942-4343-5764-6473-313031383333 XML

Metadata Language: English

Resource type: Dataset

Metadata Date: 2026-09-29T10:52:48.174Z

Metadata Standard Name: NRW

Metadata Standard Version: 1.0

pointOfContact

Natural Resources Wales (NRW) -

Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales

http://naturalresources.wales/?lang=en

Publishing Body

Access the portal

Full access to the portal and metadata.

Fluvial Audits of Welsh River Systems

Identification

Temporal Extent

Extent

Extent

Distribution

Distribution

Quality

Data quality

Keywords

Keywords

Citation

Keywords

Citation

Spatial Reference System

Content

Content Information

NRW Profile

Custom Elements

Constraints

Constraints

Limitations on Public Access and Use

Access Constraints Directive

Access Constraints Text

Use Constraints

Metadata

Metadata

Publishing Body