Lake Mead Dipstick
October 17, 2007
This is a fascinating photo of the "bathtub ring" that represents a water dipstick for the southwestern U.S. and northern Mexico. The boaters are motoring south on the Overton Arm of Lake Mead. The white calcium deposit you see is the 65-year-old water line that is considered the lake's normal water level. At this particular spot, the water level is almost 50 feet (15 m) below the lake's capacity. As of October 12, 2007, Lake Mead storage was 48% of capacity.
Lake Mead is fed by the huge Colorado River watershed, which includes streams as far away as Wyoming. Over the past 10 to 15 years, the volume of water flowing into the lake has been as low as 56% of the flow that filled the lake some 65 years ago.
The lake was created by the construction of the Hoover Dam (originally named Boulder Dam) on the Colorado River, just outside of Las Vegas, Nevada. Lake Mead is not only an essential source of water for Nevada, Arizona, and California, but also the hydroelectric generators in the dam keep the lights burning brightly on the Las Vegas Strip.