Rhwydwaith Ceuffyrdd Draenio Helygain-Milwr (Gogledd Ddwyrain Cymru)
This dataset represents the approximate locations of the Halkyn and Milwr drainage adit (tunnel) system beneath North East Wales. The adit network was constructed in the early 20th century to lower the regional water table and facilitate metal mining operations in the area.
The dataset supports understanding of groundwater drainage processes across Flintshire, where flows are significantly influenced by the presence of the adit system. The mapped locations provide a general representation of the network to inform hydrological and environmental assessments.
Please ensure the information warning in the lineage is read and complied with.
- Dull adnabod
- Rhychwant
- Dosbarthiad
- Ansawdd
- Allweddeiriau
- System Cyfeirio Gofodol
- Cynnwys
- Cyfyngiadau
- Cynnal a chadw
- Metadata
Dull adnabod
- Dynodydd
- NRW_DS161541
- Teitl Amgen
-
- Halkyn–Milwr Drainage Adit Network.lyr
- Laith Metadata
- English
- Datganiad
-
This dataset has been compiled incrementally over several years using a combination of historical records, legacy datasets, and internal knowledge sources. In some cases, the original source materials are no longer available or cannot be fully verified.
The mapped locations therefore represent an interpreted and generalised alignment of the Halkyn and Milwr adit system rather than a precise survey. Positional accuracy may vary, but the dataset is considered sufficient for providing an indicative representation of the network and supporting internal understanding of groundwater drainage processes in the area.
Information warning: the dataset is derived from historical information and should be regarded as a reference source only. Due to the age of the source material and uncertainties in the recorded and mapped locations, the accuracy and completeness of the dataset cannot be guaranteed. It is not suitable for operational use, detailed site-specific analysis, or decision-making without independent verification from the data custodian.
- Dyddiad cyfeirnod y set ddata (Creu)
- 2026-06-09
- Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
- 2026-09-04
Ystod amser
- Dyddiad cychwyn
- 2026-05-28
- Categori pwnc
-
- Geoscientific information
Rhychwant
Rhychwant
- Hyd
- Wales (WLS)
Dosbarthiad
- Fformat - Math a Disgrifiad
-
-
Geographic Information System
(
Unknown
)
- Math
-
ESRI Feature Class
-
Geographic Information System
(
Unknown
)
Ansawdd
Ansawdd Data
- Cwmpas Ansawdd
- Dataset
- Cydymffurfiad
- 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
- Eglurhad
-
This dataset has not been assessed for conformance to the referenced INSPIRE regulation.
- Gradd
- false
- Datganiad
-
This dataset has been compiled incrementally over several years using a combination of historical records, legacy datasets, and internal knowledge sources. In some cases, the original source materials are no longer available or cannot be fully verified.
The mapped locations therefore represent an interpreted and generalised alignment of the Halkyn and Milwr adit system rather than a precise survey. Positional accuracy may vary, but the dataset is considered sufficient for providing an indicative representation of the network and supporting internal understanding of groundwater drainage processes in the area.
Information warning: the dataset is derived from historical information and should be regarded as a reference source only. Due to the age of the source material and uncertainties in the recorded and mapped locations, the accuracy and completeness of the dataset cannot be guaranteed. It is not suitable for operational use, detailed site-specific analysis, or decision-making without independent verification from the data custodian.
Allweddeiriau
Allweddair
- Math
- Theme
Dyfyniad
- Dyddiad (Cyhoeddiad)
- 2008-06-01
Allweddair
-
NRW Thesaurus
-
- drainage
- hydrogeology
- Math
- Theme
Dyfyniad
- Dyddiad (Cyhoeddiad)
- 2026-08-27
System Cyfeirio Gofodol
Cynnwys
Gwybodaeth Cynnwys
Proffil CNC
Elfennau CNC
Cyfyngiadau
Cyfyngiadau
Cyfyngiadau ar Fynediad a Defnydd Cyhoeddus
- Math o Gyfyngiad
- Other restrictions
Cyfarwyddeb Cyfyngiadau Mynediad
- Cyfyngiadau
- noLimitations
Testun cyfyngiadau mynediad
- Cyfyngiadau eraill
-
There are no access restrictions on this data. NRW may release, publish or disseminate it freely.
Defnyddiwch gyfyngiadau
- Cyfyngiadau Defnyddio
- Other restrictions
- Cyfyngiadau eraill
-
© CNC/NRW. Data may be re-used under the terms of the Open Government Licence providing it is done so, acknowledging both the source and NRW's copyright. It is the recipient's responsibility to ensure the data is fit for the intended purpose.
Datganiad Priodoli
- Cyfyngiadau eraill
-
Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved.
Math o Drwydded
- Cyfyngiadau eraill
- Open Government Licence