Claerwen Reservoir
E244124
Claerwen Reservoir is a large upland water reservoir in mid Wales, known for its impressive dam and scenic surroundings within the Elan Valley.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Claerwen Reservoir canonical | 5 |
How this entity was disambiguated
This entity first appeared as the object of triple T2115148 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Claerwen Reservoir Context triple: [Rhayader, hasNearbyReservoir, Claerwen Reservoir]
-
A.
Pen-y-garreg Reservoir
Pen-y-garreg Reservoir is a scenic man-made lake in the Elan Valley of mid Wales, known for its historic stone dam and role in the region’s water supply system.
-
B.
Garreg Ddu Reservoir
Garreg Ddu Reservoir is a scenic man-made lake in the Elan Valley of mid-Wales, known for its distinctive submerged dam and role in supplying water to the city of Birmingham.
-
C.
Harperrig Reservoir
Harperrig Reservoir is a man-made freshwater reservoir in the Pentland Hills of Scotland, used for water supply, fishing, and recreation.
-
D.
Abbeystead Reservoir
Abbeystead Reservoir is a man-made lake in Lancashire, England, known for its scenic setting within the Forest of Bowland and its role in regional water supply.
-
E.
Howden Reservoir
Howden Reservoir is a large man-made lake in Derbyshire’s Peak District, known as part of the Upper Derwent Valley chain of reservoirs supplying water to nearby cities and popular for its scenic surroundings and outdoor recreation.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Claerwen Reservoir Target entity description: Claerwen Reservoir is a large upland water reservoir in mid Wales, known for its impressive dam and scenic surroundings within the Elan Valley.
-
A.
Pen-y-garreg Reservoir
Pen-y-garreg Reservoir is a scenic man-made lake in the Elan Valley of mid Wales, known for its historic stone dam and role in the region’s water supply system.
-
B.
Garreg Ddu Reservoir
Garreg Ddu Reservoir is a scenic man-made lake in the Elan Valley of mid-Wales, known for its distinctive submerged dam and role in supplying water to the city of Birmingham.
-
C.
Harperrig Reservoir
Harperrig Reservoir is a man-made freshwater reservoir in the Pentland Hills of Scotland, used for water supply, fishing, and recreation.
-
D.
Abbeystead Reservoir
Abbeystead Reservoir is a man-made lake in Lancashire, England, known for its scenic setting within the Forest of Bowland and its role in regional water supply.
-
E.
Howden Reservoir
Howden Reservoir is a large man-made lake in Derbyshire’s Peak District, known as part of the Upper Derwent Valley chain of reservoirs supplying water to nearby cities and popular for its scenic surroundings and outdoor recreation.
- F. None of above. chosen
Statements (42)
| Predicate | Object |
|---|---|
| instanceOf |
reservoir
ⓘ
upland reservoir ⓘ |
| accessibleBy | minor road from Elan Valley ⓘ |
| basinCountry | United Kingdom ⓘ |
| category |
Dams in Wales
ⓘ
Elan Valley ⓘ Reservoirs in Powys ⓘ |
| constructionMaterial | concrete ⓘ |
| constructionStartDate | 1946 ⓘ |
| country | Wales ⓘ |
| damType | gravity dam ⓘ |
| designedToSupplement | earlier Elan Valley reservoirs ⓘ |
| elevation | approximately 370 metres above sea level ⓘ |
| hasAccessRestriction |
no public boating
ⓘ
no public swimming ⓘ |
| hasFeature |
large concrete dam
ⓘ
scenic surroundings ⓘ upland setting ⓘ |
| hasPart | Claerwen Dam ⓘ |
| hasViewOf | Cambrian Mountains ⓘ |
| inflow | River Claerwen ⓘ |
| locatedIn |
Elan Valley
ⓘ
Powys ⓘ mid Wales ⓘ |
| locatedInProtectedArea |
Cambrian Mountains
ⓘ
surface form:
Cambrian Mountains region
|
| locatedNear |
Elan Valley
ⓘ
surface form:
Elan Valley Visitor Centre
|
| managedBy | Dŵr Cymru Welsh Water ⓘ |
| nearbyCity | Rhayader ⓘ |
| opened | 1952 ⓘ |
| operator | Dŵr Cymru Welsh Water ⓘ |
| outflow | River Claerwen ⓘ |
| ownedBy | Welsh Water ⓘ |
| partOf |
Elan Valley Estate
ⓘ
Elan Valley reservoirs ⓘ
surface form:
Elan Valley Reservoirs
|
| popularFor |
cycling
ⓘ
walking ⓘ wildlife watching ⓘ |
| purpose | water supply ⓘ |
| region | Ceredigion–Powys border area ⓘ |
| usedFor |
drinking water supply
ⓘ
hydroelectric power (small-scale) ⓘ |
| waterSourceFor |
Birmingham water supply system
ⓘ
surface form:
Birmingham Corporation Aqueduct system (historical planning context)
|
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Claerwen Reservoir Description of subject: Claerwen Reservoir is a large upland water reservoir in mid Wales, known for its impressive dam and scenic surroundings within the Elan Valley.
Referenced by (5)
Full triples — surface form annotated when it differs from this entity's canonical label.