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| HAER ORE,23-NYS.V,1--6 6. DAM AFTERBAY, WITH OWYHEE RIVER IN FOREGROUND, SHOWING OUTLET TUNNEL PORTAL (LEFT) AND POWERHOUSE AND ENTRANCE PORTAL TO DAM INTERIOR (RIGHT). NOTE RELEASE OF WATER FROM NEEDLE VALVE NUMBER 2 IN VALVEHOUSE ON DAM. VIEW TO SOUTHEAST. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR |
"Significance: Owyhee Dam is a 417-foat-high, concrete thick-arch dam
(or arch/gravity dam). At its completion in 1932,
Owyhee was the tallest dam in the world, a short-lived
distinction because it was superceded in 1936 with the
completion of 726-foot high Hoover Dam. Owyhee Dam
has engineering significance as the proving ground for
construction techniques developed by Bureau of
Reclamation engineers for use at Hoover Dam. Tests
conducted on the cooling and shrinking of mass
concrete as it cured at Owyhee Dam helped assure
Bureau engineers that their techniques would work at
Hoover Dam. Historic apparatus for monitoring those
tests is still in place on the interior of Owyhee Dam.
Owyhee also has engineering significance for its
ancillary features. The ring gate on the Owyhee Dam
spillway was the first ever built. It was the first
dam in which a freight elevator was installed. The
needle valves in the outlet works for Owyhee Dam,
which make it possible to regulate the discharge of
water under very high pressure, represent a late stage
in the evolution of such valves by the Bureau of
Reclamation. Upon its completion, Owyhee Dam began
storing water for use by farmers on the Owyhee
Project, one of the most important in the development
of irrigated agriculture in Oregon." [HAER_data]
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| HAER ORE,23-NYS.V,1--33 33. DETAIL OF STEEL RING AND MORNING GLORY SPILLWAY FOR OUTLET TUNNEL. VIEW TO SOUTHWEST. |
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| Underestimated Arsenal posted [The post has a long description.] |






































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