Nine gates on the Sacramento Weir will be opened at 11 p.m. Wednesday, according to the National Weather Service.
The weir diverts water from the Sacramento River to the Yolo Bypass, where the water is expected to rise rapidly once the weir gates are open.
This is the second time this winter the gates have been opened. After a deluge of heavy rains, crews on Jan. 10 lifted the gates on the flood release structure near downtown Sacramento. It was the first time since 2006 that the river rose high enough to open the structure.
The weir acts as a flood-release valve to flush excess water from the Sacramento River system into the Yolo Bypass floodplain, keeping Sacramento and towns along the river from getting swamped.