It is true…the dam and its reservoir are a big project and they sometimes produce big problems which require specially engineered solutions.
The prodigious amounts of water collected, often more than the reservoir can hold, is released over the weir at the upper end of the waste channel (spillway). After falling a hundred feet vertically in a mere 1,200 foot long channel (spillway) this vast flow gains speeds up to 15 miles per hour. Anyone who has been to the spillway in high runoff season can attest to that.