Merwin Dam
E516215
Merwin Dam is a hydroelectric dam on Washington State’s Lewis River that forms Lake Merwin and generates power for the region.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Merwin Dam canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T5314902 — 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: Merwin Dam Context triple: [Lewis River, hasDam, Merwin Dam]
-
A.
Fengman Dam
Fengman Dam is a large hydroelectric gravity dam on the Songhua River in Jilin Province, China, known for its significant role in regional power generation and flood control.
-
B.
McClure Dam
McClure Dam is a hydroelectric dam on the Dead River in Michigan, forming McClure Basin and providing power and water management for the surrounding region.
-
C.
Wyman Dam
Wyman Dam is a hydroelectric dam in Maine that impounds the Kennebec River to form Wyman Lake and generate power.
-
D.
Wyman Dam
Wyman Dam is a hydroelectric dam located on the Androscoggin River in Maine, used for power generation and river flow regulation.
-
E.
North Fork Dam
North Fork Dam is a hydroelectric and water-supply dam located on the Clackamas River in northwestern Oregon.
- 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: Merwin Dam Target entity description: Merwin Dam is a hydroelectric dam on Washington State’s Lewis River that forms Lake Merwin and generates power for the region.
-
A.
Fengman Dam
Fengman Dam is a large hydroelectric gravity dam on the Songhua River in Jilin Province, China, known for its significant role in regional power generation and flood control.
-
B.
McClure Dam
McClure Dam is a hydroelectric dam on the Dead River in Michigan, forming McClure Basin and providing power and water management for the surrounding region.
-
C.
Wyman Dam
Wyman Dam is a hydroelectric dam in Maine that impounds the Kennebec River to form Wyman Lake and generate power.
-
D.
Wyman Dam
Wyman Dam is a hydroelectric dam located on the Androscoggin River in Maine, used for power generation and river flow regulation.
-
E.
North Fork Dam
North Fork Dam is a hydroelectric and water-supply dam located on the Clackamas River in northwestern Oregon.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
gravity dam
ⓘ
hydroelectric dam ⓘ |
| basinCountry |
United States of America
ⓘ
surface form:
United States
|
| commissioningDate | 1931 ⓘ |
| constructionBegan | 1929 ⓘ |
| constructionMaterial | concrete ⓘ |
| country |
United States of America
ⓘ
surface form:
United States
|
| county |
Clark County, Washington
NERFINISHED
ⓘ
Cowlitz County, Washington NERFINISHED ⓘ |
| createsWaterBody | Lake Merwin NERFINISHED ⓘ |
| energySource | hydropower ⓘ |
| environmentalContext | Lewis River watershed NERFINISHED ⓘ |
| FERCProject | Lewis River Project NERFINISHED ⓘ |
| fishPassageMitigation | Lewis River basin fish programs ⓘ |
| formsReservoir | Lake Merwin NERFINISHED ⓘ |
| gridConnection | regional electric grid of the Pacific Northwest ⓘ |
| hasRecreationArea | Lake Merwin Campers Hideaway vicinity ⓘ |
| hasSpillway | yes ⓘ |
| impounds | Lewis River NERFINISHED ⓘ |
| installedCapacity | about 136 MW ⓘ |
| locatedIn |
Washington
ⓘ
surface form:
Washington State
|
| locatedInTimeZone | Pacific Time Zone ⓘ |
| locatedOnRiver | Lewis River NERFINISHED ⓘ |
| namedAfter | Lake Merwin NERFINISHED ⓘ |
| nearCity |
Ariel, Washington
NERFINISHED
ⓘ
Woodland, Washington NERFINISHED ⓘ |
| numberOfTurbines | 3 ⓘ |
| openingDate | 1931 ⓘ |
| operator | PacifiCorp NERFINISHED ⓘ |
| owner | PacifiCorp NERFINISHED ⓘ |
| partOf | Lewis River hydroelectric project NERFINISHED ⓘ |
| powerPlantType | conventional hydroelectric power plant ⓘ |
| providesService | regional electricity supply ⓘ |
| purpose |
flood control
ⓘ
power generation ⓘ recreation ⓘ |
| regionServed |
Pacific Northwest
ⓘ
southwestern Washington ⓘ |
| regulatoryAuthority | Federal Energy Regulatory Commission NERFINISHED ⓘ |
| reservoirName | Lake Merwin NERFINISHED ⓘ |
| reservoirShorelineUse |
camping
ⓘ
day-use recreation ⓘ |
| reservoirUse |
fishing
ⓘ
hydroelectric power generation ⓘ recreational boating ⓘ |
| riverSystem | Columbia River basin NERFINISHED ⓘ |
| state | Washington ⓘ |
| watercourseDammed | Lewis River 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: Merwin Dam Description of subject: Merwin Dam is a hydroelectric dam on Washington State’s Lewis River that forms Lake Merwin and generates power for the region.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.