Three Gorges Dam calculated based on the average flow rate at the dam site, assuming the water level is 175 m and the plant gross efficiency is 90.15%. The actual power output in 2008 was obtained based on the monthly electricity sent to the grid. The Three Gorges Dam reached its design-maximum reservoir water level of for the first time on October 26, 2010, in which the intended annual power-generation capacity of 84.7 TWh was realized. In 2012, the dam's 32 generating units generated a record 98.1 TWh of electricity, which accounts for 14% of China's total hydro generation. The State Grid Corporation
Risks to the Glen Canyon Dam of between 500–700 years. Glen Canyon Dam is a concrete arch dam on the Colorado River in northern Arizona in the United States, just north of Page. The dam was built to provide hydroelectricity and flow regulation from the upper Colorado River Basin to the lower. Its reservoir is called Lake Powell, and is the second largest artificial lake in the country, extending upriver well into Utah. The dam is named for Glen Canyon, a colorful series of gorges, most of which now lies under the reservoir. Construction of Glen Canyon Dam started in 1956 and was not finished until