Henry Hagg Lake
artificial lake in Oregon, United States
Henry Hagg Lake (also known simply as Hagg Lake) is an artificial lake in northwest Oregon, in the United States. The reservoir is an impoundment of Scoggins Creek, which drains a small portion of the eastern side of the Northern Oregon Coast Range. The lake and creek are part of the Tualatin River’s watershed in the Tualatin Valley. It is located about 5 miles (8.0 km) southwest of Forest Grove.
The lake is named for Henry Hagg, an Oregon dairy farmer who was active in local agricultural committees during the first half of the twentieth century.
Scoggins Dam
Scoggins Dam was built in 1975 by the United States Bureau of Reclamation, which still owns and operates the facility. Hagg Lake contains 53,640 acre-feet (66,160,000 m3) of water that can be used. Some water from the lake is used by Clean Water Services to augment the flow of the Tualatin River during the summer months to reduce the temperature and improve water quality. Other users include four cities and the Tualatin Valley Water District.
Ecology and Geology
In 1967, fossilized shark remains were discovered near the lake.
Begin with the source’s own compact description: “Henry Hagg Lake” is artificial lake in Oregon, United States. The dossier treats that line as a proposition to test through Henry, Hagg and Lake, not as a finished interpretation.
Why this record matters
The phrase “artificial lake in Oregon, United States” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
Place names and jurisdictional language are key evidence: both can reveal earlier catalogue descriptions and overlooked record series. The source revision retrieved here is dated Jul 25, 2026. The linked authority identifier is Q5722434. VIAF identifies the subject as 315530981. Authority coordinates are 45.473, -123.203. 1 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1975 and 1967.
Modern boundaries and familiar names can conceal earlier jurisdictions or structures that do not align with the present site. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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Treat names, boundaries and functions as historically changeable. Maps, plans, inventories and administrative records can clarify what the place meant at different dates.
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Three-step research path
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This entry incorporates text from “Henry Hagg Lake” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.