California’s Mysterious ‘Glory Hole’ Spillway Awakens After 6 Years

Mar 28, 2025 Khushi Kumari

For the first time since 2019, Lake Berryessa’s famous 'Morning Glory Spillway' is back in action

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A massive, circular drain that controls Lake Berryessa’s water levels by releasing excess water into Putah Creek

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The spillway is in eastern Napa Valley, California, near Monticello Dam, and serves as a key reservoir

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Heavy winter rains raised the lake’s water level above 440 feet, triggering the spillway on February 4, 2024

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The swirling vortex of water is a rare event, last seen in 2019, and may remain visible for another week

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With an opening 72 feet across, the spillway acts as a safety drain, preventing flooding in the area

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The spillway can be safely viewed from Highway 128 near Monticello Dam but swimming near it is strictly prohibited

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