Downsville Dam
E808158
Downsville Dam is a large earthen embankment dam on the East Branch of the Delaware River in New York, built as part of New York City's water supply system.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Downsville Dam canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T8849850 — 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: Downsville Dam Context triple: [Pepacton Reservoir, createdBy, Downsville Dam]
-
A.
Chatfield Dam
Chatfield Dam is a large flood-control and water-storage structure in Colorado that creates Chatfield Reservoir on the South Platte River near Denver.
-
B.
Waddell Dam
Waddell Dam is a major dam in Arizona that impounds the Agua Fria River to form Lake Pleasant, a key water storage and recreation reservoir for the Phoenix metropolitan area.
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C.
Forestville Dam
Forestville Dam is a hydroelectric and recreational dam located on the Dead River near Marquette in Michigan’s Upper Peninsula.
-
D.
Milner Dam
Milner Dam is an early 20th-century irrigation and hydroelectric dam on the Snake River in southern Idaho that helps divert water for agriculture and power generation.
-
E.
Gillespie Dam
Gillespie Dam is an early 20th-century concrete gravity dam on Arizona’s Gila River, historically used for irrigation and now noted as a local landmark and wildlife habitat area.
- 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: Downsville Dam Target entity description: Downsville Dam is a large earthen embankment dam on the East Branch of the Delaware River in New York, built as part of New York City's water supply system.
-
A.
Chatfield Dam
Chatfield Dam is a large flood-control and water-storage structure in Colorado that creates Chatfield Reservoir on the South Platte River near Denver.
-
B.
Waddell Dam
Waddell Dam is a major dam in Arizona that impounds the Agua Fria River to form Lake Pleasant, a key water storage and recreation reservoir for the Phoenix metropolitan area.
-
C.
Forestville Dam
Forestville Dam is a hydroelectric and recreational dam located on the Dead River near Marquette in Michigan’s Upper Peninsula.
-
D.
Milner Dam
Milner Dam is an early 20th-century irrigation and hydroelectric dam on the Snake River in southern Idaho that helps divert water for agriculture and power generation.
-
E.
Gillespie Dam
Gillespie Dam is an early 20th-century concrete gravity dam on Arizona’s Gila River, historically used for irrigation and now noted as a local landmark and wildlife habitat area.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
earthen dam
ⓘ
embankment dam ⓘ gravity dam ⓘ |
| basinCountry |
United States of America
ⓘ
surface form:
United States
|
| builtBy | City of New York Board of Water Supply NERFINISHED ⓘ |
| catchmentArea | East Branch Delaware River watershed NERFINISHED ⓘ |
| constructionBegan | 1947 ⓘ |
| constructionMaterial | earth and rock fill ⓘ |
| country |
United States of America
ⓘ
surface form:
United States
|
| createsReservoir | Pepacton Reservoir NERFINISHED ⓘ |
| crosses | East Branch Delaware River NERFINISHED ⓘ |
| damType | earth-fill embankment ⓘ |
| hasAccessRoad | yes ⓘ |
| hasFunction | regulates East Branch Delaware River flows ⓘ |
| hasOutletWorks | yes ⓘ |
| hasReservoir | Pepacton Reservoir NERFINISHED ⓘ |
| hasSpillway | yes ⓘ |
| height | about 201 feet ⓘ |
| impounds | Pepacton Reservoir NERFINISHED ⓘ |
| length | about 2,400 feet ⓘ |
| locatedIn |
Delaware County, New York
NERFINISHED
ⓘ
New York State NERFINISHED ⓘ Town of Colchester NERFINISHED ⓘ Upstate New York NERFINISHED ⓘ |
| locatedInCounty | Delaware County NERFINISHED ⓘ |
| locatedInRegion | Catskill Mountains NERFINISHED ⓘ |
| locatedInWatershed | Delaware River watershed ⓘ |
| locatedNear | Downsville, New York NERFINISHED ⓘ |
| locatedOnRiver | East Branch Delaware River NERFINISHED ⓘ |
| namedAfter | Downsville, New York NERFINISHED ⓘ |
| nearbySettlement | Hamlet of Downsville NERFINISHED ⓘ |
| nearbyWaterbody | Pepacton Reservoir NERFINISHED ⓘ |
| openingDate | 1954 ⓘ |
| operator | New York City Department of Environmental Protection NERFINISHED ⓘ |
| owner |
New York City
ⓘ
surface form:
City of New York
|
| partOf |
Delaware System of NYC water supply
NERFINISHED
ⓘ
New York City water supply system NERFINISHED ⓘ |
| partOfInfrastructure | New York City water supply reservoirs and dams ⓘ |
| purpose |
flood control
ⓘ
flow regulation ⓘ municipal water supply ⓘ |
| regionServed | downstate New York ⓘ |
| reservoirCapacity | about 140 billion US gallons ⓘ |
| servesPopulation | New York City metropolitan area NERFINISHED ⓘ |
| status | operational ⓘ |
| usedFor |
drinking water storage
ⓘ
river flow augmentation ⓘ |
| waterSupplyFor | New York City 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: Downsville Dam Description of subject: Downsville Dam is a large earthen embankment dam on the East Branch of the Delaware River in New York, built as part of New York City's water supply system.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.