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How the West was Lost

The Colorado River at it delta (Photo: Peter McBride)
The Colorado River at it delta (Photo: Peter McBride)

Just as the settling and development of the arid American West was fueled by harnessing its available fresh water, the growing lack of water availability may well be its undoing.

California’s epic drought is just the latest example of what is shaping up to be the new normal out west.  Last year was the driest on record.  This year, river flows are so low that deliveries of surface water to the southern half of the state, through California’s complex network of aqueducts and canals, were slashed to zero.  Thirsty homeowners and anxious farmers have been forced to dig more and deeper wells to tap into steadily declining groundwater reserves.

Several cities and towns in California have imposed mandatory restrictions in order to curtail water use. The State Water Resources Control Board recently authorized fines of up to $500 for wasting water on washing down sidewalks or for overwatering yards.   A new study from the University of California, Davis estimates that the current drought will cost the state $2.2 billion in damages, and will result in 17,000 jobs lost.

Such severe drought is becoming more commonplace across the western United States. Just a few years ago, the 2011 Texas drought was raging at full throttle.  Nationwide media coverage regularly confronted us with graphic images of emaciated longhorns, desiccated fields and burning prairie grass.  Stories of small towns literally running out of water made headlines.

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Toughing it out in the 2011 Texas drought. Photo by Austin American Statesman

In between California and Texas, there is scarce little green space to be had. Colorado, Utah, Nevada and Arizona are all in the grips of a multiyear ‘big dry,’ with only the last vestige of this past winter’s average snowpack in Colorado to hang their hopes on.  Lake Mead, our country’s largest reservoir, is at its lowest level ever.

Can it get any worse?  I’m afraid so.

Today, the journal Geophysical Research Letters published a new study from our research team on groundwater depletion in the Colorado River Basin.  Quite honestly, we are alarmed and concerned about the implications of our findings.  From a group that studies groundwater depletion in the hottest of the hot spots of water stress around the world — in India, the Middle East, and in California’s Central Valley – that says something.

The Colorado River Basin is the water lifeline of the western United States.  It provides water to roughly 40 million people in 7 states and to Mexico.   It supplies water to major metropolitan regions including several of the country’s largest and driest — Los Angeles, San Diego, Phoenix and Las Vegas — and enough water to support irrigation on 4 million acres of farmland.  As the water future of the Colorado River Basin goes, so does that of the west.

In our new study, we used NASA satellites to find that between December 2004 and November 2013, the Colorado River Basin lost a total of 65 cubic kilometers of water, or roughly the equivalent of two full Lake Meads.  This was a period of prolonged drought in which the water levels in Lake Mead and Lake Powell (the United States’ second largest reservoir) had fallen to dangerously low levels, and were being carefully managed to prevent further declines. Surprisingly, we found that 75% of the water lost was from the Basin’s groundwater supplies.

Such behavior is normal in times of drought.  Groundwater is the strategic reserve when persistent drought limits rainfall and snowmelt that would normally feed our rivers and replenish our aquifers. It allows local water managers to bridge the shortfall between supply and demand, and farmers to secure precious irrigation water and continue to grow food to put on the nation’s tables.

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The map above combines data from the satellites of the NASA Gravity Recovery and Climate Experiment (GRACE) with other satellite and ground-based measurements to model the relative amount of water stored in underground aquifers in the continental United States. The wetness, or water content, is a depiction of the amount of groundwater on July 7, 2014, compared to the average from 1948 to 2009. Areas shown in blue have more abundant groundwater for this time of year than comparable weeks over the long-term, while shades of red depict deficits compared to this time of year.
The maps are an experimental product used by the U.S. Drought Monitor and supported by NASA’s Goddard Space Flight Center. The measurements are derived from observations of small changes in Earth’s mass and its gravity field—features that are affected by the movement and storage of water and ice around the planet.
From the National Drought Mitigation Center and NASA Earth Observatory.

However, in many parts of the west, groundwater is non-renewable.  When we use it, it’s gone.  Moreover, in most western states, in contrast to management of our surface water in rivers and reservoirs, groundwater management can be loose and difficult to enforce, and in some cases non-existent.

When it comes to groundwater, the west can truly be wild. If you own the property, the vagueries of groundwater law often mean that you can dig the wells and pump to your heart’s content.  Multiply that by millions of private wells and you get the picture.

The undeniable consequence is that groundwater supplies in our major western aquifers — the Central Valley, the southern Ogallala and now those that underlie the Colorado River Basin – are disappearing. We simply pump out more water than is being naturally replenished, and as a result, groundwater levels are falling rapidly.

This is a problem if, as the best available science tells us, the frequency and severity of drought will continue to increase in the coming decades.  After the groundwater is gone, there is no more backup.

The American West is running out of water.

This weekend, representatives from the 7 basin states, the Bureau of Reclamation and the Department of the Interior will meet to discuss future water management strategies for the Colorado River basin.   It is important that this group recognize the following implications for this and future Basin management discussions.

Monthly groundwater storage changes (black) and surface water storage changes (green) for a) the entire Colorado River Basin (green line represents Lakes Powell and Mead; b) Upper Basin (green line represents Lake Powell); and c) Lower Basin (green line represents Lake Mead. From Castle et al., 2014, Groundwater depletion during drought threatens future water security of the Colorado River basin, Geophysical Research Letters

First, in the western United States, we use far more water than what is renewable by natural precipitation and snowmelt.  Our rivers and reservoirs are simply no longer enough.  We rely on groundwater far more than we are ready to admit.

Second, groundwater is already being used to supplement declining surface water resources, and under the severe drought conditions of the past decade, the Basin has been over-allocated by a much as 30%.  Groundwater has been filling the gap between supply and demand.

Third, if we expect to continue to use groundwater as a strategic reserve, then we’d better embark on some strategic management, before our aquifers drop to critically low and perhaps irrecoverable levels.

Without a regulatory framework for jointly managing surface and groundwater resources as ‘one water,’ groundwater levels will continue to fall, basin water managers will be challenged to meet future allocation commitments, and the water security of the western United States will be seriously threatened.

That could mean a far drier future with profound socioeconomic consequences for a vast swath of the western U. S. and its major urban centers.  Considering the similar situations in America’s fruit bowl, California’s Central Valley, and its bread basket, the Ogallala aquifer, agriculture in the United States would be difficult to sustain.

My colleague, Bill Patzert, the oft-quoted climatologist at NASA’s Jet Propulsion Laboratory, got it right in a recent quote when he said ‘the American West is on the ropes.’   If we don’t take action soon, it will be down for the count.  Sadly, there will be no water left to splash on its face to help it recover.

Jay Famiglietti is Senior Water Scientist at the NASA Jet Propulsion Laboratory of the California Institute of Technology, and a professor of Earth System Science at the University of California, Irvine.  The opinions expressed here are his alone.

Comments

  1. Jay Gee
    DC
    September 18, 2:29 pm

    California is naturally a desert climate and the current agriculture practice of irrigation is proving unsustainable. Some Central Valley farmers are now shelling out $1M to purchase their own well drilling rigs to beat the year wait list but that’s a stop gap measure. Some areas of the Central Valley have had a 30 foot ground subsidence since 1925 due to pumping the aquifers. That ground will not be rising again. The problem is not inadequate water. You can’t expect much water in a desert. The problem is the current agricultural model in California that depends on more water than can be expected. Three years of drought show the vulnerability. Some zillionaire in Mendocino dug up his million dollar landscaping and replaced it with something that will grow there: cactus. We humans have to adjust to the local conditions, not vice versa.

  2. Bruce Gionet
    07024
    July 28, 5:16 pm

    Clearly the amount if water used to support landscaping not intended for the desert is a design problem that can be solved over time. Sorry golfers, I recommend bocci.

  3. Wayne Lusvardi
    July 28, 1:28 pm

    I respectfully believe Famiglietti’s alarm is exaggerated. The 1977 California drought was as severe as this one but groundwater bounced back — except for in the Tulare Basin. The Tulare Basin will deplete in 390 years and is doing so at a rate of 0.25% per year — not quite what Famiglietti reports.
    Aggregating groundwater statistics across basins is deceptive. Depletion is a basin-specific phenomenon.

    See table here: http://calwatchdog.com/wp-content/uploads/2014/03/Water-chart.png

    In Southern California’s 9 adjudicated groundwater basins there is unlikely to be depletion because they are monitored and overseen by the courts.

    Even in Siskiyou County along the California-Oregon border where the Environmental Law Foundation is suing the county for overdrafting groundwater impacting the Scott River, the groundwater basin in adjudicated and thus unlikely to be depleted. That there isn’t enough water to share with kayakers, commercial fishermen, and Indian Tribes (all political constituencies of the current party in power) does not mean that the basin is necessarily being depleted. And dividing the water further among not only hay farmers but those free riders who don’t want to pay for the water or maintain the adjudicated basin is only going to make it worse.

    I worked for a large regional water district for 20 years. I have come across depleted water basins in the Barstow area of Southern California. So I know and have seen with my own eyes the decimation of a water basin. But I don’t believe we can say with great certainty that groundwater is being depleted permanently in California based on the historical record.

    Even the Colorado River reservoirs were as low as they are today in the 1930′s.

    The historical difference with this drought is that in Calfironia 64% of the system water is allocated to fish and the environment in a wet year, when it is supercritical to store up water for dry years. A 2004 U.C. Berkeley study concluded that where water could be best conserved is with water for wildlife refuges and fish runs. Taking 2 million acre feet of water and flushing it to the sea to literally wash salmon out to the sea over the 60-mile natural hump in the San Joaquin River is not an effective or efficient way to be a good steward of water resources. Perhaps that is a good place to start.

  4. Tricia Gerrodette
    United States
    July 24, 3:08 pm

    Along the Mexican border, the only green river left between Texas and California is the San Pedro. It still has natural perennial stretches but they are diminishing. Groundwater depletion is well studied in this basin.