California is coming out of a multi-year drought with massive flooding; as much as 10 inches of rain last weekend in Northern California, resulting in reservoirs overflowing, levees being topped, mud and rock slides, and dam outflows collapsing, with as much as 200,000 gallons a second released in some locations.
The spillway at Lake Berryessa in California's Napa Valley is pretty unique. It works like a sink drain to automatically lower the water level behind the Monticello Dam when it gets to a certain height. The concrete funnel is 72 feet wide, and automatically goes to work when the water reaches 440 feet above sea level.
This is the first time in the last 10 years that the reservoir has been high enough for the Glory Hole Spillway to work, and it's the first time it has been filmed in action by drone. The Glory Hole Spillway is draining at about two million gallons a minute in this video (35,000 gallons a second).