Sacramento River Watershed:
The Sacramento River Watershed includes 21 counties in California, which are divided into 6 subregions.
The Northeast Subregion includes the Upper Sacramento River, McCloud River, and Pit River Watersheds.
The Eastside Subregion includes Stillwater-Churn, Cow Creek, Bear Creek, Battle Creek, Paynes-Antelope, Mill Creek, Deer Creek, Big Chico Creek, and Butte Creek Watersheds.
The Sacramento River Valley Subregion includes the Sacramento Valley area.
The Westside Subregion includes Clear Creek, Cotton Creek, Tehama West, Stony Creek, Cache Creek, and Putah Creek Watersheds.
The Feather River Subregion includes Upper and Lower Feather River Watersheds.
The American River Subregion includes Bear River, Lower and Upper American River, and Yuba River Watersheds.