Oahe Dam Oahe Dam The Oahe Dam is a large earthen dam on the Missouri River, just north of Pierre, South Dakota, United States. The dam creates Lake Oahe, the fourth largest man-made reservoir in the United States. The reservoir stretches up the course of the Missouri to Bismarck, North Dakota. The dam's power plant provides electricity for much of the north-central United States. It is named for the Oahe Indian Mission established among the Lakota Sioux in 1874. The project provides flood control, Hydropower generation, irrigation, and navigation benefits. Oahe Dam is one of six Missouri River mainstem dams, the next
Koyna Dam the dam was strengthened, followed by strengthening the spillway section in 2006. Now the dam is expected to be safe against any future earthquake, including ones with a higher intensity than that of 1967. Koyna Dam The Koyna Dam is one of the largest dams in Maharashtra, India. It is a rubble-concrete dam constructed on Koyna River which rises in Mahabaleshwar, a hillstation in Sahyadri ranges. It is located in Koyna Nagar, Satara district, nestled in the Western Ghats on the state highway between Chiplun and Karad. The main purpose of the dam is hydroelectricity with some irrigation in neighboring