(Bloomberg View) -- California is not unique in experiencing a destructive feedback loop in which declining water resources are devoted to energy production, and energy is required to transport water where it is increasingly scarce. Throughout much of the U.S. and the world, we manage water and energy as if they were unrelated. In reality, they are Siamese twins.

Utility executives in Washington State are concerned that low snowpack threatens reservoirs that generate much of the state’s power. Legislators in Texas, who are normally reluctant to acknowledge the existence of climate change or to spend tax dollars, approved billions of dollars in new water projects to deal with a seemingly endless drought. Nevada water officials worry that they will no longer be able to withdraw water from behind Hoover Dam if the water level continues dropping. (Meanwhile, upstream Glen Canyon Dam, which loses up to 10% of its water to evaporation and seepage under the best circumstances, remains commissioned to generate electricity.)

The energy-water feedback loop is even worse in emerging economies, where energy production siphons more water, and water delivery requires more power. Mining and burning coal, and refining oil, use 20% of China’s water supply, and an even higher proportion in the nation's arid Northwest. As a result, China has been forced to use very expensive and inefficient “dry cooling” technology in many of its coal-power plants. Having devoted too much water to mining coal, China recently abandoned many efforts to extract natural gas from shale because the shale is located in regions that lack the water required for hydrofracking.