STS068-273-056 Lake Ouiachic, Mexico October 1994 Located in the foothills of the Sierra Madre Occidental, Lake Ouiachic (also referred to as the Lever Obregon Reservoir) can be seen in this south-southwest looking view. Lake Ouiachic is fed by and drained by the Yaqui River. The dam was completed in 1952 with the purpose to regulate water flow of the Yaqui River, prevent floods, and generate electricity. Lake Ouiachic is also an expanding tourist and resort area specializing in fishing, boating, and water skiing.