High Quality Content by WIKIPEDIA articles! Sacramento River National Wildlife Refuge is located along the Sacramento River in the Sacramento Valley of California. Landscape is very flat, bordered by the Sierra and Coast ranges, with intensive agriculture (rice, with walnut, almond, and prune orchards along the river). This riparian community is one of the most important wildlife habitats in California and North America. The refuge is currently in an active acquisition phase, and includes the Llano Seco Unit. Large-scale riparian habitat restoration is ongoing. Riparian habitat along the Sacramento River is critically important for various threatened species, fisheries, migratory birds, plants, and the natural system of the river itself.