The dam’s morning glory type spillway, known as the Glory Hole, is 72 feet (22 m) in diameter at lake level and narrows down to about 28 feet (8.5 m) at the exit. At the lake’s peak level the spillway can drain 48,400 cubic feet per second (1,370 m3/s), which occurs when the lake level rises to 15.5 feet (4.7 m) above the level of the funnel.
Water spills over its lip when the lake reaches 1,602,000 acre feet (1.976×109 m3) and a reservoir elevation of 440 feet (130 m) above sea level. The last time the reservoir naturally spilled through the glory hole was on the afternoon of February 16, 2017.
