Both the main and the emergency spillway send water into the Feather river.
When the reservoir is at capacity, the dam operator has no control over how much water goes into the Feather River nor whether downstream towns are flooded or not. Any water not going down the main spillway will go down the emergency spillway and into the river.
When the reservoir is at capacity, the dam operator has no control over how much water goes into the Feather River nor whether downstream towns are flooded or not. Any water not going down the main spillway will go down the emergency spillway and into the river.
(edit for typo)