California's Doomsday Water Cycle
California's Doomsday Water Cycle
In California and around the world, water supply and carbon-based energy production are locked in a destructive feedback cycle. Fossil fuel extraction and combustion consume water -- lots of it. Obtaining and delivering water, in turn, requires energy -- lots of it. Too little of one yield shortages of the other. Climate change -- the result of burning too much fossil fuel while destroying forests and soils -- accelerates this cycle, disrupting the equilibrium between climate and water that enables civilization.
Vast amounts of water are required at each stage of fossil energy production. Every kilowatt hour of electricity generated in the U.S. from coal, oil or gas sucks 25 gallons of water out of the nation's rivers and streams. Half of U.S. water withdrawals for cooling systems are devoted to electricity generation by coal plants.
Refining a barrel of U.S. crude oil into gasoline or diesel takes between one and two barrels of water. Extracting shale gas in the arid Rocky Mountain West requires 3 million to 8 million gallons of fresh water per gas well. (You can't fracture the rock and release the gas without water.)
Even some low-carbon energy sources, such as nuclear and hydro, need water. (Solar and wind -- not so much.) In both the U.S. and Europe, hot summers have forced temporary shut-downs of nuclear plants that cannot be safely cooled.
Likewise, industrial water systems are enormous energy gluttons. Providing water for U.S. homes consumes up to 30,000 kwh for every million gallons. India uses 25 percent of all its electricity on irrigation. Half the cost of desalinizing sea water is devoted to energy.
California is ground zero for this vicious feedback loop. The trigger is a familiar villain -- drought. The state is entering the 10th dry year of the past 14. The signature of climate change is everywhere apparent. According to a state official, California snow pack is so low it is "completely obliterating the previous record." Ground water levels in some parts of the state have dropped by 50 to 60 feet.
Higher temperatures increase the amount of water that trees and crops need to survive. More fossil fuel burning will lead to reduced water supplies. And shortages of water will require more fossil fuel burning to move water to customers. It's a death dance.
To cope, Governor Jerry Brown has declared the first mandatory state-wide rationing in history-- 25 percent. California’s farmers face drastic reductions in water for irrigation. In Kern County, farmers this year are receiving only half their usual water deliveries. In desperation, they have turned to over-pumping underground aquifers, threatening the region's long-term water supply.
Even as Brown rations water for urban lawns, computer manufacturing and toilets, California continues to dedicate enormous amounts of water to producing energy. This year, 1.3 billion gallons of water are being injected into oil fields to extract heavy crude -- 320 gallons for every barrel of oil pumped. By the time that oil reaches the pump at a local gas station, 45 gallons of water will have been used to produce every gallon of fuel.
Accessing all this water takes a lot of energy. Pumping and treating water is one of the state’s largest electricity drains -- consuming 19 percent of the state's total power. California’s State Water Project uses 2 to 3 percent of the state’s electricity just to pump water over the Tehachapi Mountains. Drilling ever-deeper wells has steadily increased the energy required to irrigate fields.
The shortfall of snow and rain has slashed available hydro-power. California is emitting 8 percent more carbon dioxide and other pollutants now than it would with normal rain and snow falls. As dams dry up, the state is forced to use more fossil power requiring -- yes, more water.
The California crisis exposes the perverse connection between water-supply and energy-supply systems. It also highlights the influence of climate change on this drought, combining heat, loss of snow, increased evaporation and, as a result, greater demand for diminishing supplies of water. A recent study concluded that continuing climate change would greatly worsen California’s water problems, raising temperatures and reducing the snow pack that stores a third of the state’s supply.
California has already promised its water consumers far more than Mother Nature will deliver -- even without climate change. Now, overuse of fossil fuels threatens the climate required to provide the water on which fossil-fuel energy depends.
The politics of climate denial doesn't help the situation. California’s (undeclared) contribution to the 2016 Republican presidential field, Carly Fiorina, claims that the drought is a problem only because environmentalists won't let the state build more reservoirs. Of course, without new rain, new reservoirs would be empty.
Solutions require a different mindset. First, “climate change" and “water shortage” are linked concepts: They go together. Second, we must recognize that the "water-energy nexus," as the State of California dubs it, is a global fact, not a California fad. Today’s vicious feedback cycle comes from waste and excess. The solutions require elegance and thrift. If we accelerate the shift toward low-carbon energy and water efficiency, the vicious, unsustainable cycle between water and energy will slow. Indeed, eventually, it can run in reverse.
To contact the author on this story:
Carl Pope at Carldpope@gmail.com
To contact the editor on this story:
Francis Wilkinson at firstname.lastname@example.org