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Water Supplies Severely Depleted

By Mira Rojanasakul, Christopher Flavelle, Blacki Migliozzi and Eli Murray

The New York Times

Global warming has focused concern on land and sky as soaring temperatures intensify hurricanes, droughts and wildfires. But another climate crisis is unfolding, underfoot and out of view.

Many of the aquifers that supply 90% of the nation’s water systems, and which have transformed vast stretches of America into some of the world’s most bountiful farmland, are being severely depleted.

These declines are threatening irreversible harm to the American economy and society as a whole.The New York Times conducted one of the most comprehensive examinations of groundwater depletion nationwide and found that America’s life-giving resource is being exhausted in much of the country, and in many cases it won’t come back. Huge industrial farms and sprawling cities are draining aquifers that could take centuries or millenniums to replenish themselves, if they recover at all.

States and communities are already paying the price.

Groundwater loss is hurting breadbasket states like Kansas, where the major aquifer beneath 2.6 million acres of land can no longer support industrial-scale agriculture. Corn yields have plummeted. If that decline were to spread, it could threaten America’s status as a food superpower.

Fifteen hundred miles to the east, in New York state, overpumping is threatening drinking-water wells on Long Island, birthplace of the modern American suburb and home to working class towns as well as the Hamptons and their beachfront mansions.

Around Phoenix, one of America’s fastest growing cities, the crisis is severe enough that the state has said there’s not enough groundwater in parts of the county to build new houses that rely on aquifers.

In other areas — including parts of Utah, California and Texas — so much water is being pumped up that it is causing roads to buckle, foundations to crack and fissures to open in the earth. And around the country, rivers that relied on groundwater have become streams or trickles or memories.

“There is no way to get that back,” Don Cline, the associate director for water resources at the United States Geological Survey, said of disappearing groundwater. “There’s almost no way to convey how important it is.”

This analysis is based on tens of thousands of groundwater monitoring wells that dot the nation. The Times collected data for these wells, which are widely scattered and often poorly tracked, from dozens of federal, state and local jurisdictions.

That database reveals the scope of the crisis in many ways. Every year since 1940, for example, more wells have had falling water levels than rising levels.

One of the biggest obstacles is that the depletion of this unseen yet essential natural resource is barely regulated. The federal government plays almost no role, and individual states have implemented a dizzying array of often weak rules.

The problem is also relatively unexamined at the national scale. Hydrologists and other researchers typically focus on single aquifers or regional changes.

All of this helps enable and reinforce practices that have drained aquifers, such as growing water-intensive crops such as alfalfa or cotton in dry areas and overreliance on groundwater in fast-growing urban areas.

Several states — including Texas, Oklahoma and Colorado — have rules that allow groundwater to be pumped from some regions until it’s gone. Some areas have even set official timelines for how quickly they plan to use up groundwater over the next few decades.

Oklahoma is working to determine how much water remains in its aquifers, information that state lawmakers could use to set limits on pumping. But Christopher Neel, the head of water rights for the Oklahoma Water Resources Board, said people might not necessarily welcome the government telling them that their land is running out of groundwater.

“If we start showing that kind of data, that kind of goes into your property values,” Neel said. “If we show an area may be depleted in, let’s say, two years, well, if someone tries to sell that property, they’re not going to be able to.”

To get the clearest picture possible of the state of groundwater in the United States, the Times interviewed more than 100 scientists, policymakers and hydrological experts in addition to building its national database of millions of measurements from wells used to measure groundwater depth.

The analysis of that data — some of it collected from wells that have been tracked for a century — enabled the Times to cross-reference water levels over time with crop cover and population patterns. Results were also compared against readings from sophisticated satellites that can estimate groundwater changes from space by measuring subtle shifts in gravity.

Recent data from those satellites, which are operated by the Jet Propulsion Laboratory and funded by NASA, also show aquifers in decline.

Two major California and Arizona aquifers recently matched or exceeded their lowest levels since NASA began collecting data two decades ago, according to research by Bridget Scanlon and Ashraf Rateb at the University of Texas at Austin. And parts of the vast Ogallala Aquifer beneath Kansas, eastern Colorado and the Oklahoma and Texas panhandles — an aquifer that irrigates a huge share of the global food supply — last year reached their lowest levels since the start of NASA’s program. The gravity-measuring satellites are part of NASA’s mission to study the workings of the planet.By draining aquifers that filled up over thousands or millions of years, regions risk losing access to that water in the future when they might need it even more, as climate change makes rainfall less predictable or droughts more severe.

“From an objective standpoint, this is a crisis,” said Warigia Bowman, a law professor and water expert at the University of Tulsa. “There will be parts of the U.S. that run out of drinking water.”

The most visible symbol of America’s agricultural bounty is the “center pivot” irrigation system, a metal contraption on wheels that is attached to a pump and revolves around a central point. A single arm, mounted with sprinklers, can be as long as half a mile, dispersing hundreds of gallons per minute from a well, 24 hours a day, for weeks or months on end.

Across much of the High Plains, the landscape is dominated by these pivots.

But a visitor to Wichita County, in western Kansas, will see fewer of them. The reason: There’s little water left to lay down. The wells have begun to go dry.

Irrigation can more than double the amount of corn grown per acre. As farms in the area use up the groundwater, corn yields have declined, erasing decades of gains.

The region offers a glimpse into the future of America’s farming industry if groundwater keeps getting used up.

“We overpumped it,” said Farrin Watt, who has been farming in Wichita County for 23 years. “We didn’t know it was going to run out.”

American agriculture didn’t always rely on pulling huge volumes of water out of the ground. Until the middle of the last century, farmers were mostly limited to relying on rainfall or river water. Smaller wells were mainly just supplements.

But advances in pump technology after World War II created an American agricultural powerhouse, turning the West and the High Plains into a bounty of corn, alfalfa and other crops, delivering yields that surface water alone couldn’t support.

That success has relied on pumping up more water than nature could put back.

As recently as the late 1990s, Wichita County farmers produced 165 to 175 bushels of corn per acre, well above the national average. But it came at a cost, requiring farmers to drain the aquifer in order to irrigate their crops. The area gets less than 20 inches of rain a year, on average, about one-third less than the continental United States as a whole — not nearly enough to replace the water being pumped from the ground.

As farmers ran out of water, they increasingly switched to what’s called dryland farming, relying on rain alone.

That change is reflected in corn yields over time. Last year, corn growers nationwide produced an average of 173 bushels per acre. But for Wichita County, the yield was just 70.6 bushels, the lowest in more than six decades.

It’s not just Kansas depleting its aquifers at a vicious clip. The same thing is playing out in areas around the country.

In Colorado, residential development and reduced precipitation have increasingly strained the state’s groundwater. But Colorado has policies that allow its aquifers to run out.

Kevin Rein is the Colorado official in charge of allocating the state’s groundwater. He said his office does not track how much water remains in Colorado’s section of the Ogallala, or project how much time remains before that water is exhausted, because state lawmakers haven’t given him that authority.

But even without that data, Rein said, farmers can already see their wells running low on water. “They might say, ‘Tell us something we don’t know,’ ” he said.

A little more than one-third of America’s total volume of drinking water comes from groundwater, according to data from the USGS. But small and rural communities are disproportionately dependent on wells, which typically cost less than treating and transporting water from rivers and lakes.

Of the nation’s 143,070 water systems, 128,362 rely primarily on groundwater, according to the Environmental Protection Agency.

The effects of the nation’s dwindling supplies of groundwater are visible in another way: The ground itself is breaking apart.

In southwest Utah, at the edge of an otherwise fast-growing city named Enoch, are the outlines of a neighborhood that appears to have vanished. Streets and sidewalks meander past lots that were once meant for houses but now have only bits of trash and waist-high weeds.

Arizona, to the south, has 169 miles of mapped earth fissures, according to the Arizona Geological Survey, an office at the University of Arizona. In 2007, a fissure killed a horse that fell into a crack and couldn’t be freed.

In the Houston area, overpumping of groundwater, along with oil extraction, has caused some land to sink by more than 10 feet over the course of decades, according to local officials. In Florida, overpumping sometimes causes sinkholes.

But Enoch, population 8,000 or so, is a glaring example of subsidence.

A developer began laying out a subdivision during the housing boom of the mid-2000s, planning 800 homes. The project went bankrupt, a victim of the housing crash. Then, city workers noticed something that prevented other developers from trying again: an unusual crack in the road. The subdivision, it turned out, sat atop an earth fissure.

Pumping water can cause the earth above an aquifer to slump, collapsing the space left behind by the water that was removed. Once that space is lost, it can no longer hold water.

That process, called subsidence, is happening around the country, and more than 80% of it is the result of groundwater use, according to the USGS. The agency says subsidence has affected more than 47,000 square miles of land and waterways across the United States.

As the land sinks, home foundations, sewer pipes and other structures are damaged. But among the most dramatic consequences of subsidence is a fissure. As softer ground slumps, sometimes an adjacent patch of ground stays put. The resulting movement shears the earth apart.

“We’re sucking water out, and it’s compressing the ground,” said Rob Dotson, Enoch’s city manager.

It’s hard to predict fissures before they open. But once they happen, they can’t easily be filled in or closed. Instead they tend to get both wider and longer.

Enoch’s new neighborhood had to be abandoned. And the fissure has since been detected in another neighborhood nearby, where people already live.

Yet despite knowing the consequences, Enoch has been unable to stop extracting its groundwater, a decision to keep pumping that is being repeated nationwide in cities and on farmland. After all, there are crops to sustain and communities like Enoch that keep growing.

 

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