The Sacramento Weir is the only manually operated weir on the Sacramento River system.
While the system’s five other weirs overflow automatically once the river reaches a certain elevation, the 1,920-foot-long Sacramento Weir consists of 48 gates that must be opened with a long hooked pole. The gates are opened when the river level at the I Street Bridge reaches 29.87 feet. The weir, built in 1916, was last opened in December 2005.
How it works:
▪ Each gate consists of 38 hinged wooden planks
▪ 1,500 cubic feet of water per second can move through each gate
Source: California Department of Water Resources