Ogōchi Dam
E747021
Ogōchi Dam is a large concrete dam in Okutama, Tokyo, that forms Lake Okutama and serves as a major source of drinking water and flood control for the Tokyo metropolitan area.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Ogōchi Dam canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T8627337 — 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: Ogōchi Dam Context triple: [Okutama, hasDam, Ogōchi Dam]
-
A.
Nagayasuguchi Dam
Nagayasuguchi Dam is a hydroelectric dam located on Japan’s Yoshino River, used primarily for power generation and flood control.
-
B.
Shimen Dam
Shimen Dam is a major concrete gravity dam in northern Taiwan that provides water supply, flood control, and hydroelectric power as part of the Shimen Reservoir system.
-
C.
Ukai Dam
Ukai Dam is a major multi-purpose reservoir and hydroelectric dam in Gujarat, India, built on the Tapi River for irrigation, power generation, and flood control.
-
D.
Hidase Dam
Hidase Dam is a massive hydroelectric dam on the Blue Nile in Ethiopia, designed to be one of Africa’s largest power-generating and infrastructure projects.
-
E.
Surobi Dam
Surobi Dam is a hydroelectric and irrigation dam located on the Kabul River in eastern Afghanistan.
- 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: Ogōchi Dam Target entity description: Ogōchi Dam is a large concrete dam in Okutama, Tokyo, that forms Lake Okutama and serves as a major source of drinking water and flood control for the Tokyo metropolitan area.
-
A.
Nagayasuguchi Dam
Nagayasuguchi Dam is a hydroelectric dam located on Japan’s Yoshino River, used primarily for power generation and flood control.
-
B.
Shimen Dam
Shimen Dam is a major concrete gravity dam in northern Taiwan that provides water supply, flood control, and hydroelectric power as part of the Shimen Reservoir system.
-
C.
Ukai Dam
Ukai Dam is a major multi-purpose reservoir and hydroelectric dam in Gujarat, India, built on the Tapi River for irrigation, power generation, and flood control.
-
D.
Hidase Dam
Hidase Dam is a massive hydroelectric dam on the Blue Nile in Ethiopia, designed to be one of Africa’s largest power-generating and infrastructure projects.
-
E.
Surobi Dam
Surobi Dam is a hydroelectric and irrigation dam located on the Kabul River in eastern Afghanistan.
- F. None of above. chosen
Statements (49)
| Predicate | Object |
|---|---|
| instanceOf |
concrete dam
ⓘ
gravity dam ⓘ |
| constructionEndDate | 1957 ⓘ |
| constructionStartDate | 1938 ⓘ |
| country | Japan ⓘ |
| formsBodyOfWater | Lake Okutama NERFINISHED ⓘ |
| hasAccessRoad | Tokyo Metropolitan Route 411 (Ome Kaido) NERFINISHED ⓘ |
| hasClimateImpact | local microclimate moderation around Lake Okutama ⓘ |
| hasEmergencyRole | flood peak reduction on Tama River ⓘ |
| hasFunction |
drought mitigation for Tokyo
ⓘ
regulation of Tama River flow ⓘ |
| hasJapaneseName | 小河内ダム ⓘ |
| hasNearbyFacility |
Ogōchi Dam management office
ⓘ
visitor observation deck ⓘ |
| hasNearbyRailwayStation | Okutama Station NERFINISHED ⓘ |
| hasSpillwayType | gated overflow spillway ⓘ |
| hasTourism | viewing of autumn foliage ⓘ |
| hasUse |
flood control
ⓘ
hydroelectric power generation ⓘ industrial water supply ⓘ irrigation water supply ⓘ |
| height | approximately 149 meters ⓘ |
| isAccessibleBy | bus from Okutama Station ⓘ |
| isImportantFor | urban water security of Tokyo ⓘ |
| isMajorWaterSourceFor |
Tama area
NERFINISHED
ⓘ
Tokyo 23 wards NERFINISHED ⓘ Tokyo metropolitan area NERFINISHED ⓘ |
| isSubjectOf | environmental and social impact studies ⓘ |
| isUpstreamOf |
Hamura Diversion Weir
NERFINISHED
ⓘ
Tamagawa Josui (Tama Aqueduct) NERFINISHED ⓘ |
| length | approximately 353 meters ⓘ |
| locatedIn | Okutama, Tokyo NERFINISHED ⓘ |
| locatedInAdministrativeEntity | Tokyo Metropolis NERFINISHED ⓘ |
| locatedInNationalPark | Chichibu Tama Kai National Park NERFINISHED ⓘ |
| locatedInRiverBasin | Tama River basin ⓘ |
| namedAfter | Ogōchi village NERFINISHED ⓘ |
| nearSettlement | Okutama town NERFINISHED ⓘ |
| openingDate | 1957 ⓘ |
| operator | Tokyo Metropolitan Government NERFINISHED ⓘ |
| owner | Tokyo Metropolitan Government NERFINISHED ⓘ |
| partOf | Tokyo water supply system NERFINISHED ⓘ |
| primaryUse | drinking water supply ⓘ |
| region | Kantō region ⓘ |
| reservoirAlsoKnownAs | Ogōchi Reservoir NERFINISHED ⓘ |
| reservoirName | Lake Okutama NERFINISHED ⓘ |
| reservoirSurfaceArea | approximately 4.25 square kilometers ⓘ |
| reservoirTotalCapacity | approximately 189,000,000 cubic meters ⓘ |
| riverCrossed | Tama River NERFINISHED ⓘ |
| submergedFormerSettlement | Ogōchi village NERFINISHED ⓘ |
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: Ogōchi Dam Description of subject: Ogōchi Dam is a large concrete dam in Okutama, Tokyo, that forms Lake Okutama and serves as a major source of drinking water and flood control for the Tokyo metropolitan area.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.