Jay Famiglietti, Jet Propulsion Laboratory
It’s been just over a year since my interview with Don Cheadle for the “Death of the Central Valley” story for Years of Living Dangerously (Season 2, Episode 3). I would love to report that the epic California drought has run its course, and that threats to the water and food security of the Golden State have all but dissipated. Unfortunately, nothing could be further from the truth.
While the winter of 2015–2016 delivered ‘average’ amounts of rain and snow to the northern half of the state, it did little to reverse falling reservoir levels, restore depleted river flows, or replenish critical groundwater supplies statewide.
Nowhere is this clearer than in California’s Central Valley, where once vast groundwater reserves fueled the transformation of this great valley into one of the most productive agricultural regions in the world.
Today, however, drought, climate change, and an overreliance on groundwater for irrigation have driven Central Valley aquifer levels to record lows. As a result, more and more wells are running dry, challenging farmers to identify reliable water sources of water.
In 2015, 7% of irrigated farmland — 550,000 acres — was fallowed, owing to the lack of available water. Other farms have opted to relocate to relatively water-abundant states, like North Dakota, Kansas, or Florida.
Food production as we know it in California is changing, right before our eyes.
Simultaneously, socioeconomic inequities over access to fresh water are emerging in the Central Valley. Only wealthier individuals and larger farms can afford to dig deeper and more expensive wells, which can cost as much as $300,000. Ironically, it is often water use by large farms that is responsible for the failing wells and the declining access of its workers.
If you thought that all of this was playing out invisibly beneath the ground, then guess again.
Large swaths of land across the Central Valley are literally sinking in response to the disappearance of massive amounts of groundwater. Over the last year, rates of land subsidence have increased to the fastest ever recorded, sinking by as much as 3 feet per year in some locations, causing damage to buildings, roads, bridges, rail lines, canals and other critical infrastructure.
Exacerbating the problem, the year 2015 saw a 500% increase (relative to the 30-year average) in the number of groundwater wells drilled in the southern half of the Central Valley, in what can be described as a race to the bottom of the aquifer.
California must immediately embraces its new reality. Climate change, population growth, a water-intensive agriculture sector and a corresponding long-term overreliance on groundwater have all conspired to create a condition of chronic water scarcity.
Even in the absence of drought, California no longer has all the water that it needs to do all the things that it wants. A century’s worth of irrigation-driven groundwater depletion is the smoking gun.
California’s water future will require many difficult choices that must protect and sustain its precious groundwater reserves for generations to come.
Primary among these will be how much water to allocate for food production (far and away the largest use of water in California and around the world) versus how much to provide for the environment, for domestic, municipal and industrial use, and for energy production.
As a scientist and a science communicator, I have struggled to convey the message that California is literally running out of water, although it is abundantly clear from synthesis of all available observations.
It is also a message that is sometimes ignored, for example, with the lifting of statewide mandatory water conservation earlier this year. Is it any surprise that with such inconsistent messaging to the public, that municipal conservation rates dropped from 27% to 17% over the last twelve months?
Yet we can no longer afford to ignore the science. Chronic water scarcity is real, and one of its key drivers, climate change, is no friend to California hydrology.
Climate change will impact virtually every aspect of water flow and storage in the state, from reduced snowfall in the mountains, to reduced streamflow in rivers to reduced replenishment of groundwater. The increasing frequency of flooding and drought will pose new threats to all plant and animal life in the state, while presenting new challenges to water managers. Massive tree die-offs and a lengthening fire season are already realities.
In fact, among the most palpable impacts of climate change are impacts to water, not only in California, but globally. Moreover, the world’s hotspots for water scarcity are also coincident with those for threats to food production, for violent conflict, for political instability and for mass migration.
Shows like Years of Living Dangerously are essential for spreading these messages to millions of people around the world, across all ages and from all walks of life. In California, and in the other regions of chronic water scarcity around the globe, the era of water abundance is over. Water and climate change are intimately linked, and climate change is here to stay. Hence, regional water scarcity and related food, energy and human security issues are here to stay as well.
It’s time to act accordingly. A long-term commitment to a new, more water-efficient and water-aware way of life is at the core of California’s future, as well as the other chronically-water scarce regions of the world.
Jay Famiglietti appears as a featured expert Years of Living Dangerously Season 2 Episode 3. He is a hydrologist, a science communicator and the Senior Water Scientist at the Jet Propulsion Laboratory at the California Institute of Technology. The opinions stated here are his alone. Follow him on Twitter @jayfamiglietti