 The Snake River flows northwest through the Bonneville County, beginning at the Wyoming border as the Palisades Reservoir.The river exits the county about midway on its northern border, turns and re-enters approximately 20 miles (32 km) west to flow southwest through Idaho Falls .As of the census of 2000, there were 82,522 people, 28,753 households, and 21,449 families living in the county.