Folsom Lake
E178927
Folsom Lake is a large man-made reservoir in Northern California known for recreation, water storage, and flood control near the Sacramento area.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Folsom Lake canonical | 18 |
| Folsom Lake State Recreation Area | 5 |
How this entity was disambiguated
This entity first appeared as the object of triple T1561657 — 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: Folsom Lake Context triple: [American River, hasReservoir, Folsom Lake]
-
A.
Shasta Lake
Shasta Lake is a large reservoir in Northern California known for its extensive shoreline, houseboating, and proximity to Mount Shasta.
-
B.
Lake Oroville
Lake Oroville is a large man-made reservoir in Northern California, created by the Oroville Dam on the Feather River, that serves as a major source of water storage, flood control, and recreation.
-
C.
Oroville
Oroville is a small city in Northern California known for its proximity to the Oroville Dam and Lake Oroville recreation area.
-
D.
Folsom Dam
Folsom Dam is a large concrete dam on the American River in California that provides flood control, water storage, and hydroelectric power for the Sacramento region.
-
E.
Shasta Dam
Shasta Dam is a large concrete gravity dam on California’s Sacramento River, forming Shasta Lake and serving as a key source of water storage, hydroelectric power, and flood control for the state.
- 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: Folsom Lake Target entity description: Folsom Lake is a large man-made reservoir in Northern California known for recreation, water storage, and flood control near the Sacramento area.
-
A.
Shasta Lake
Shasta Lake is a large reservoir in Northern California known for its extensive shoreline, houseboating, and proximity to Mount Shasta.
-
B.
Lake Oroville
Lake Oroville is a large man-made reservoir in Northern California, created by the Oroville Dam on the Feather River, that serves as a major source of water storage, flood control, and recreation.
-
C.
Oroville
Oroville is a small city in Northern California known for its proximity to the Oroville Dam and Lake Oroville recreation area.
-
D.
Folsom Dam
Folsom Dam is a large concrete dam on the American River in California that provides flood control, water storage, and hydroelectric power for the Sacramento region.
-
E.
Shasta Dam
Shasta Dam is a large concrete gravity dam on California’s Sacramento River, forming Shasta Lake and serving as a key source of water storage, hydroelectric power, and flood control for the state.
- F. None of above. chosen
Statements (49)
| Predicate | Object |
|---|---|
| instanceOf |
man-made lake
ⓘ
reservoir ⓘ |
| basinCountry |
United States of America
ⓘ
surface form:
United States
|
| constructionBegan | 1951 ⓘ |
| country |
United States of America
ⓘ
surface form:
United States
|
| createdBy | Folsom Dam ⓘ |
| elevation | approximately 466 feet above sea level at full pool ⓘ |
| formedBy | impoundment of the American River ⓘ |
| hasDam | Folsom Dam ⓘ |
| inflow |
American River (California)
ⓘ
surface form:
American River
North Fork American River ⓘ South Fork American River ⓘ |
| locatedIn |
California, United States
ⓘ
surface form:
California
El Dorado County ⓘ Northern California ⓘ Placer County ⓘ Sacramento County ⓘ |
| locatedInValley | Sierra Nevada foothills ⓘ |
| locatedNear |
Folsom
ⓘ
Sacramento ⓘ |
| maximumCapacity | approximately 977000 acre-feet ⓘ |
| notableFor | exposed historical sites during low water levels ⓘ |
| operator |
Bureau of Reclamation
ⓘ
surface form:
United States Bureau of Reclamation
|
| outflow |
American River (California)
ⓘ
surface form:
American River
|
| partOf | Central Valley Project ⓘ |
| partOfProtectedArea |
Folsom Lake
self-linksurface differs
ⓘ
surface form:
Folsom Lake State Recreation Area
|
| primaryUse |
flood control
ⓘ
hydroelectric power generation ⓘ irrigation ⓘ municipal water supply ⓘ recreation ⓘ water storage ⓘ |
| recreationActivity |
boating
ⓘ
camping ⓘ fishing ⓘ hiking ⓘ horseback riding ⓘ mountain biking ⓘ swimming ⓘ water skiing ⓘ |
| servesCity |
Folsom
ⓘ
Sacramento ⓘ |
| servesRegion | Sacramento metropolitan area ⓘ |
| shoreLength | approximately 75 miles ⓘ |
| subjectTo | California drought conditions ⓘ |
| surfaceArea | approximately 11500 acres ⓘ |
| waterManagementAgency |
Bureau of Reclamation
ⓘ
surface form:
United States Bureau of Reclamation
|
| waterSourceFor | Central Valley agriculture ⓘ |
| yearCompleted | 1955 ⓘ |
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: Folsom Lake Description of subject: Folsom Lake is a large man-made reservoir in Northern California known for recreation, water storage, and flood control near the Sacramento area.
Referenced by (23)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Folsom Lake State Recreation Area
this entity surface form:
Folsom Lake State Recreation Area
this entity surface form:
Folsom Lake State Recreation Area
this entity surface form:
Folsom Lake State Recreation Area
this entity surface form:
Folsom Lake State Recreation Area