Lake Mead was created in 1936, when the Colorado River was dammed in the Black Canyon along the Nevada and Arizona border, by what is now known as the Hoover Dam. The Hoover Dam was built in order to create a water supply for Arizona, California, and Nevada, and also to generate electricity by hydro power. When Lake Mead is at maximum capacity, it is the largest reservoir in the United States. At maximum capacity Lake Mead is 112 miles long, has 759 miles of shoreline, is 532 feet at greatest depth, with a surface elevation of 1,221.4 feet above sea level, and has 247 square miles of surface, and when filled to capacity has 26.12 million acre feet of water.
The last 5 images are of the Colorado River merging into Lake Mead. You can see where the Colorado River ends by the murkiness of the water. The two water bodies look so different in color because of the sediments flowing through the Colorado River.