Duncan Dam No. 2, located in Usk, Washington, is a privately owned earth dam built in 1966 for irrigation purposes along the Pend Oreille River. The dam stands at a hydraulic height of 18 feet and a structural height of 15 feet, with a length of 325 feet. With a normal storage capacity of 95 acre-feet and a maximum storage of 150 acre-feet, the dam serves as a vital water resource for the surrounding area.

Despite its low hazard potential, Duncan Dam No. 2 is regulated by the Washington Department of Ecology and undergoes regular state inspections and enforcement measures to ensure its structural integrity. The dam also offers recreational opportunities in addition to its primary irrigation function, further highlighting its importance in the region. With a drainage area of 0.5 square miles and a maximum discharge of 139 cubic feet per second, the dam plays a crucial role in water management along the Pend Oreille River.

As a key component of the local water infrastructure, Duncan Dam No. 2 represents a blend of functionality and environmental stewardship. With a focus on both water supply and recreational activities, the dam serves as a vital resource for the community while also maintaining a low hazard potential. Its location within the scenic landscape of Pend Oreille, Washington, adds to its significance as a sustainable water management structure for the region.