The Nimbus Fish Hatchery sits at the base of Nimbus Dam, where the American River exits Lake Natoma, and is operated by the California Department of Fish and Wildlife. Its primary job is raising chinook salmon and steelhead trout to supplement runs that have been disrupted by the dams blocking the river.
The best time to visit is October and November, when adult salmon return from the ocean and crowd into the holding pools below the dam in astonishing numbers — tens of thousands of fish stacked fins-to-fins in the clear water. The hatchery is free to visit and has viewing areas where you can watch the fish and learn about the lifecycle and the role hatcheries play in the Sacramento River salmon recovery programme. From the hatchery you can walk west along the river trail toward the Sacramento American River Parkway. The hatchery is off Hazel Avenue in Rancho Cordova, about eight kilometres west of downtown Folsom.