A: There are four types of hiatal hernias. Most hiatal hernias are called type I or âsliding hernias,â where the stomach intermittently slides up into the chest through a small opening in the diaphragm. Sliding hernias are very common, and most donât require surgery.: There are four types of hiatal hernias. Most hiatal hernias are called type I or âsliding hernias,â where the stomach intermittently slides up into the chest through a small opening in the diaphragm. Sliding hernias are very common, and most donât require surgery.
Shasta Dam, which was completed in 1945 on the upper Sacramento River northwest of Redding, is the second-largest reservoir run by the Bureau of Reclamation in the country, behind Grand Coulee Dam in Washington.
Construction is now under way in China on what will be the world's largest hydroelectric dam. When it is completed in 2009, Three Gorges Dam will stretch more than one mile across the Yangtze River and soar 600 feet above the valley floor. It will be the largest concrete dam in the world, and will produce 18,000 megawatts of electrical energy, nudging Brazil's Itaipu Dam to second place.