The dam is located in the northeast corner of Washington state , just south of the border with British Columbia , Canada .
Boundary Dam is a concrete arch gravity - type hydroelectric dam on the Pend Oreille River , in the U.S. state of Washington .
The dam is located in the northeast corner of Washington   , just south of the border with British Columbia , Canada .
Boundary Dam is a concrete arch gravity - type hydroelectric dam on the Pend Oreille River , in the U.S. state of Washington .