Hoover Dam, one of the most iconic dams ever constructed, has reached its lowest water level in history.
Hoover Dam is an arch-gravity dam made of concrete and is located at the Black Canyon, Colorado. It was completed in 1936 to divert the Colorado river with the aim to efficiently provide water for agriculture, generate hydroelectric power and control flooding. The project was a pioneering construction that started during the Great Depression and provided occupation for numerous laborers. Nonetheless, many laborers lost their lives during its construction. Its height is about 220 meters and its reservoir capacity approximately 35 square kilometers. The dam currently provides water to 25 million people in the western United States. More on the history of the Hoover dam can be found here.
In early June 2021, the water level of the dam dropped to 326.6 meters above sea level setting the lowest level in history when the previous record was documented in 2016. The reservoir's annual high and low Elevations from 1935 to 2020 can be found here.
The conditions of the reservoir are concerning since only one drop of more than 40 meters has been observed during the past 2 decades. It is currently only 37% full and the federal government officially declared a water shortage. The problematic situation derives from the extreme drought that has recently struck the Western United Stated. Droughts are natural phenomena that periodically occur and their impact has been controlled over the years, however, scientists agree that their frequency and intensity have increased, a fact that can be associated with human-induced climate change. Climate change can be blamed for higher temperatures during spring and summer (that lead to more wildfires), less snow accumulation during the winter and durable dry seasons. According to the U.S. Bureau of Reclamation, the current period is the driest one that the Western United States have experienced in 115 years.
As the conditions keep deteriorating, officials are implementing emergency measures. Arizona declared an emergency and ordered evacuations after 586.8 square kilometers of land were devastated by fires. The Regional Water Authority in Sacramento suggested that providers of water should drill more wells admitting that this is a temporary solution. Moreover, it recommended that customers voluntarily reduce their water consumption by 10%. In California, 41 out of the 58 counties declared a drought emergency.
At this point, officials anticipate July's monsoon season to strike in the southwestern States and provide a temporal solution. "We're just desperately looking to the forecast to see when the monsoon might show up," Michael Crimmins, a University of Arizona climate scientist, stated.