Green Peter Dam releases water through its spillways. Green Peter Dam is located on the Middle Santiam River near Sweet Home, Oregon. The Corps operates Green Peter Dam and 12 other dams and reservoirs in the Willamette River Basin. All contribute to a water resource management system that provides flood risk management, power generation, irrigation, water quality improvement, fish and wildlife habitat and recreation on the Willamette River and many of its tributaries. Since their completion, the dams have cumulatively prevented more than $20 billion in flood damages to the Willamette Valley.