Fremont Weir Wildlife Area is a 1,461-acre protected riparian landscape in California at the north end of the Yolo Bypass floodway along the Sacramento River, spanning parts of Sutter and Yolo counties near Woodland. Beside the Fremont Weir, it occupies land where excess Sacramento River water spills into the bypass when river levels rise. This flat Central Valley habitat, averaging about 25 feet above sea level, supports valley oaks, willows, sycamores, cottonwoods, muskrat, river otter, pheasant, valley quail, and waterfowl. The area joins wildlife conservation with flood control by helping reduce flood risk for Sacramento and other nearby river communities.