What is a pond weir?
What is a pond weir? Question: What is a weir for a pond or lake? Answer: A weir is a form of control structure. And the design of that weir is for the water level to get to a certain level and it flows over the weir, which will release the water.
When was the last time water went over the spillway at Hoover dam?
The spillways have been used twice. The first time, in 1941, was a test of the system. The second time, in 1983, was for a flood.