Hetch Hetchy Regional Water System
E546722
The Hetch Hetchy Regional Water System is a major water supply and delivery network that provides high-quality drinking water from Sierra Nevada sources to San Francisco and numerous Bay Area communities.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Hetch Hetchy Regional Water System canonical | 5 |
| Hetch Hetchy aqueduct | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T5754586 — 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: Hetch Hetchy Regional Water System Context triple: [San Francisco Peninsula reservoir system, partOf, Hetch Hetchy Regional Water System]
-
A.
Hetch Hetchy Power System
The Hetch Hetchy Power System is a municipal hydroelectric power network that generates and delivers clean electricity to San Francisco and surrounding public facilities.
-
B.
Pepacton Reservoir
Pepacton Reservoir is a large man-made lake in the Catskill Mountains of New York that serves as a major component of New York City's drinking water supply system.
-
C.
Hetch Hetchy Valley
Hetch Hetchy Valley is a glacially carved valley in Yosemite National Park, California, best known for its scenic granite cliffs and for being largely submerged by the Hetch Hetchy Reservoir that supplies water to the San Francisco Bay Area.
-
D.
West Basin of Ashokan Reservoir
The West Basin of Ashokan Reservoir is the western section of the Ashokan Reservoir in New York’s Catskill Mountains, serving as part of a major water supply system for New York City.
-
E.
Abiquiu Reservoir
Abiquiu Reservoir is a man-made lake in northern New Mexico known for its scenic desert landscape, recreational opportunities, and role in regional water storage and management.
- 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: Hetch Hetchy Regional Water System Target entity description: The Hetch Hetchy Regional Water System is a major water supply and delivery network that provides high-quality drinking water from Sierra Nevada sources to San Francisco and numerous Bay Area communities.
-
A.
Hetch Hetchy Power System
The Hetch Hetchy Power System is a municipal hydroelectric power network that generates and delivers clean electricity to San Francisco and surrounding public facilities.
-
B.
Pepacton Reservoir
Pepacton Reservoir is a large man-made lake in the Catskill Mountains of New York that serves as a major component of New York City's drinking water supply system.
-
C.
Hetch Hetchy Valley
Hetch Hetchy Valley is a glacially carved valley in Yosemite National Park, California, best known for its scenic granite cliffs and for being largely submerged by the Hetch Hetchy Reservoir that supplies water to the San Francisco Bay Area.
-
D.
West Basin of Ashokan Reservoir
The West Basin of Ashokan Reservoir is the western section of the Ashokan Reservoir in New York’s Catskill Mountains, serving as part of a major water supply system for New York City.
-
E.
Abiquiu Reservoir
Abiquiu Reservoir is a man-made lake in northern New Mexico known for its scenic desert landscape, recreational opportunities, and role in regional water storage and management.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf | water supply system ⓘ |
| componentOf | San Francisco Regional Water System NERFINISHED ⓘ |
| country |
United States of America
ⓘ
surface form:
United States
|
| governedBy | San Francisco Public Utilities Commission policies ⓘ |
| hasComponent |
Bay Area pipelines
ⓘ
Hetch Hetchy Aqueduct NERFINISHED ⓘ Hetch Hetchy Reservoir NERFINISHED ⓘ O'Shaughnessy Dam NERFINISHED ⓘ local storage reservoirs ⓘ water treatment facilities ⓘ |
| locatedIn |
California, United States
ⓘ
surface form:
California
San Francisco Bay Area ⓘ |
| notableFeature |
gravity-fed long-distance aqueduct
ⓘ
mountain snowmelt as primary source ⓘ |
| operator | San Francisco Public Utilities Commission NERFINISHED ⓘ |
| owner | City and County of San Francisco NERFINISHED ⓘ |
| primaryWaterSource |
Hetch Hetchy Reservoir
NERFINISHED
ⓘ
Sierra Nevada NERFINISHED ⓘ |
| purpose |
drinking water delivery
ⓘ
fire protection water supply ⓘ support of municipal and industrial uses ⓘ urban water supply ⓘ |
| region | Sierra Nevada to San Francisco Bay Area NERFINISHED ⓘ |
| regulates | municipal water supply for San Francisco ⓘ |
| relatedTo |
Hetch Hetchy Valley
NERFINISHED
ⓘ
Yosemite National Park NERFINISHED ⓘ |
| servesPopulation | 2.5 million people (approximate) ⓘ |
| serviceArea |
East Bay
NERFINISHED
ⓘ
San Francisco Peninsula NERFINISHED ⓘ South Bay NERFINISHED ⓘ |
| suppliesWaterTo |
Alameda County communities
ⓘ
City and County of San Francisco NERFINISHED ⓘ San Mateo County communities ⓘ Santa Clara County communities ⓘ |
| usesAqueduct |
Bay Division Pipelines
NERFINISHED
ⓘ
Hetch Hetchy Aqueduct NERFINISHED ⓘ |
| usesReservoir |
Calaveras Reservoir
NERFINISHED
ⓘ
Crystal Springs Reservoir NERFINISHED ⓘ Hetch Hetchy Reservoir NERFINISHED ⓘ San Andreas Reservoir NERFINISHED ⓘ San Antonio Reservoir NERFINISHED ⓘ |
| waterQuality | high-quality drinking water ⓘ |
| waterSource |
Cherry Reservoir
NERFINISHED
ⓘ
Lake Eleanor NERFINISHED ⓘ groundwater ⓘ local Bay Area reservoirs ⓘ |
| waterTreatment | filtration and disinfection ⓘ |
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: Hetch Hetchy Regional Water System Description of subject: The Hetch Hetchy Regional Water System is a major water supply and delivery network that provides high-quality drinking water from Sierra Nevada sources to San Francisco and numerous Bay Area communities.
Referenced by (6)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Hetch Hetchy aqueduct