I am fascinated by water.
Maybe it’s because of my last name. Or because I have one kidney and am keenly aware of its need for healthy hydration. Or because I grew up five miles from a Great Lake and have spent nearly all my adult life even closer to a Mighty River.
Or maybe it’s because my wife and I have had the good fortune of raising our family directly above the massive Memphis Sand Aquifer and its estimated 57-100 trillion gallons of cool, clear, clean water.
We don’t buy bottled water. We don’t filter our tap water. We just turn on the faucet, fill a glass, and drink. We don’t really pay for the aquifer water we use. We pay the local utility to pump it, mildly treat it, and pipe it to us.
Memphis is the largest city in America that gets all its drinking water from groundwater rather than from surface water, such as rivers and lakes. The average residential customer in Memphis pays about $12 a month for water. That’s about $3.20 per 1,000 gallons. Only residents of Orlando, Florida, pay less.
Most of the water stored in our aquifer fell as rain 2,000-3,000 years ago, according to the most recent scientific estimates. That’s a long time ago to you or me, but in the realm of geology, it’s like a few seconds.
Lucky us. Our drinking water is clean, cheap, plentiful, accessible — and easy to take for granted.
We use aquifer water around here to make sweet tea and craft beer. We use it to cook and clean and flush. We use it to water our lawns, fields, and ponds. We use it to manufacture everything from yeast and cooking oil to steel and air conditioners and medical devices. We let our faucets drip, our fountains and hoses run, and our pipes leak without a second thought. We use it to cool power plants and, more and more, data centers.
“We are the Saudi Arabia of water,” says Larry J. Smith, an environmentalist, local water expert, and lifelong Memphian. “We have so much of it, almost no one really thinks much about it or cares where it comes from, how we get it, or what might be happening to it.”
Smith has been thinking about and caring for our groundwater and surface water for decades in his various roles for the Mid-South Peace and Justice Center, the Wolf River Conservancy, the Shelby County Health Department, and the Tennessee Department of Environment and Conservation. He knows where toxins were spilled, discharged, burned, buried, and abandoned.
He also knows that the liquid treasure buried in sand hundreds of feet beneath our feet is connected to the land, surface water, rainwater, and changing climate — and to the civilization and its toxins above — in ways we still are working to identify and understand.
The aquifer water that fell as rain more than 2,000 years ago — and that we pump and pour into our daily lives in Memphis and across the Mid-South — isn’t inexhaustible.
Roy Van Arsdale and Randy Cox
The thick layers of sand, silt, gravel, and clay that naturally collect, filter, and protect our drinking water aren’t impenetrable.
The patchwork of local, state, regional and federal ordinances, laws, agencies, and utilities that oversee the use of this invaluable natural resource is — to put it mildly — inadequate.
“The reality is, our groundwater is unmanaged,” says The Blue Print, a document prepared by Protect Our Aquifer that is being used to develop Shelby County’s first-ever groundwater protection plan. “New research continues to reveal more about our geology and threats of contamination. We must begin treating and managing the Memphis Sand Aquifer as the foundation of our livelihoods, because it truly is.”
I wanted to see for myself. So I asked Larry Smith and other local water experts to take me on a guided tour of the Memphis Sand Aquifer. It wasn’t as easy as touring Graceland. You can see Graceland. You can’t visit the massive, underground marvel made millions of years ago. There are no road signs inviting you to see Rock Sand Clay City.
I took a sort of conceptual journey. Along the way, my guides took me millions of years back in time, hundreds of feet below ground, and many miles across the county, the region, and the world. It was a fascinating water ride.
Most of the water stored in our aquifer fell as rain 2,000-3,000 years ago, according to the most recent scientific estimates. That’s a long time ago to you or me, but in the realm of geology, it’s like a few seconds.
The hydrogeologic formation that captures, filters, holds, and yields our drinking water took tens of millions of years to form. Water was already here. It has been here for at least four billion years. Water is old as dirt. Literally.
Geologists don’t measure time in hours, days, or years. They measure it in eons, eras, and epochs — in periods of time that span millions and billions of years. I didn’t have that much time. So I asked Randy Cox and Roy Van Arsdale, two geology professors at the University of Memphis, to give me a primer on the geological formation known as the Mississippi Embayment.
The Embayment is not a lovely coastal bay on the coast. It’s a multistate, sediment-filled trough that contains multiple aquifers including ours. “It’s a giant, natural water treatment system,” Van Arsdale says, “and it’s right here under our feet.”
At that moment, our feet were inside a coffee shop on Highland Street, so named because it runs along slightly elevated land on what was once the eastern edge of Memphis. Now the “Highland Heights” area is in the middle of the city. Millions of years ago, it was in the middle of a mountain range as high as the Smokies.
“The southern end of what is now the Appalachians and the eastern end of what is now the Ouachitas in Arkansas were one continuous mountain range,” Van Arsdale says. What happened to our mountains? Geology happened.
Van Arsdale and Cox explained it all in “The Mississippi’s Curious Origins,” their groundbreaking (figuratively speaking) 2006 article in Scientific American. They were the first geologists to deduce how complex tectonic, erosional, and depositional forces turned our interior highlands into a gulf coastal plain. In geology, depositional refers to the ways in which sediments, soil, and rocks are deposited over time by water, wind, ice, and gravity.
Shelby County Health Department: Alan Morella, Lead Technical Specialist; Sonja Owens, Operations Manager; Bailey Bynum, Technical Specialist.
It all started hundreds of millions of years ago, after the continents broke apart. The North American plate kept sliding to the west. Our part of the plate — already weakened by all the pushing and pulling — slid very, very slowly over a volcanic hotspot (the same one that later created Bermuda).
Over tens of millions of years, this region rose and fell like a hot-air balloon, says Van Arsdale, which “inflates and rises when the gas jets are turned on, When the gas jets are turned off, there is no more hot air inflating the balloon; the balloon deflates, and it descends.”
Our region rocked up — as much as three kilometers, or almost two miles, up — then rolled back down. “When the region cooled, it deflated and sank,” Van Arsdale says. “The eroded top became a depression in the landscape three kilometers deep.”
“Over the years, Sparta Sand water quality decreased due to over-pumping, which causes deeper, saltier water to come up and into the water wells. I worry the same thing could happen to the Memphis aquifer.” — Randy Cox
That long, thumb-shaped depression is now known as the Mississippi Embayment. It’s a northern extension of the gulf coastal plain — without the gulf. It runs along the Lower Mississippi River Valley from rocky southern Illinois (where it’s only a few yards deep), through the Memphis area (more than half a mile deep), all the way down to the gulf (nearly two miles deep).
Fortunately, Mother Nature didn’t leave behind a big, empty ditch. Sea levels rose and fell. The embayment was repeatedly flooded by the gulf, causing marine sediments to accumulate. When the sea receded, the ancient Mississippi River and its tributaries carried water, mud, sand, and gravel into the ditch. More layers of sediment accumulated.
“I’ve seen graphics that show each layer as a deep bowl, but those are exaggerations,” Van Arsdale says. “The layers are more like a stack of thin pancakes sitting on top of a solid bedrock plate. And the plate is cracked.”
Those cracks — seismic stretch marks where the North American plate nearly tore apart north of here — are now known as the New Madrid Seismic Zone, which triggered some of the largest earthquakes in U.S. history in 1811 and 1812. The quakes are what inspired Van Arsdale to spend more time investigating the embayment.
Cox was motivated by more personal reasons. He grew up in El Dorado, Arkansas, a Delta town about 250 miles southwest of Memphis. “El Dorado was an oil boomtown full of geologists and wanna-be geologists, so I became one,” he says.
When Cox was a kid, El Dorado’s sole source of industrial, commercial, and drinking water was the Sparta Sand Aquifer. That’s what people in Arkansas, Mississippi, and Louisiana call the Memphis Sand Aquifer.
In the late 1990s, the U.S. Geological Survey warned El Dorado to cut its water use by 72 percent or risk irreparable damage to the aquifer. Today, El Dorado draws water from the Ouachita River as well as the aquifer. The county’s three largest industries — an oil company and two chemical companies — all use river water.
“Over the years, Sparta Sand water quality decreased due to over-pumping, which causes deeper, saltier water to come up and into the water wells,” Cox says. “I worry the same thing could happen to the Memphis aquifer.”
So do a lot of other people. Not sea water. Contaminated water.
I used to think of our aquifer as a big underground lake. I was wrong. It isn’t a buried body of water. It’s a buried body of water-soaked sand. It isn’t a Great Lake. It’s a Great Sand Box.
That’s why it’s called the Memphis Sand. That’s the name two hydrogeologists gave it in 1969. Before G.K. Moore and D.L. Brown published their pioneering study of our aquifer, it was simply referred to as the “500-foot sand” — the average depth of the sand below Shelby County. (There’s also a deeper “1,400-foot sand” called the Ft. Pillow Aquifer. It supplies drinking water to parts of northern Mississippi, Millington, and West Memphis.)
The Memphis Sand extends far beyond the arbitrary human borders of Shelby County. If you could peel off the layers of soil, surface water, shallow groundwater, and clay above it, the Memphis Sand would look like a giant beach that juts up more than 500 miles from the Gulf Coast. That beach would cover most of West Tennessee, eastern Arkansas, and northwest Mississippi, as well as parts of six other states, from the southern tip of Illinois to the bottom of Louisiana. In most areas, the sand would be hundreds of feet thick.
“There’s a lot of sand beneath our feet, and the spaces between those sand grains hold a lot of water,” says Rodrigo Villalpando-Vizcaino, a research faculty member for the University of Memphis’s Center for Applied Earth Science and Engineering Research (CAESER).
How much water? No one knows for sure. CAESER estimates that there are 57 trillion gallons beneath Shelby County, and more than 100 trillion gallons under the entire eight-state region. By comparison, Lake Ontario, the smallest Great Lake, holds about 400 trillion gallons of water. But measuring drops of aquifer water between grains of sand buried hundreds of feet in the ground is a bit more complicated.
“The Memphis aquifer is more like a mixture of different types of sand, with some silts and clays here and there,” Villalpando-Vizcaino says. “It can have different colors, grain sizes, and textures depending on the location and depth.”
Faculty members, alongside graduate and undergraduate students at CAESER (formerly the Ground Water Institute), have been studying the Memphis Sand Aquifer and its component layers since the 1990s. Along the way, they’ve collected thousands of sediment samples with sand, silts, and clays from the different systems. The samples are stored in more than 6,500 tiny plastic bags and 6,000 small wooden boxes in the basement of the old Navy hospital in Millington, now the site of the Mississippi Embayment Research Center at the University of Memphis’s Millington campus.
“We once thought the Shallow Aquifer was unimportant, but now we believe that it’s a vital factor in the quantity and quality of the Memphis aquifer.” — Brian Waldron
“The boxes were taking up too much space, so we started using bags,” says Md. Saddam Hossain, the center’s repository logistics coordinator and a CAESER staff member. “The bags also make it easier for our researchers to use the samples.”
Groundwater is the world’s most extracted raw material, according to the National Ground Water Association. Freshwater aquifers supply nearly half of the world’s drinking water and more than 40 percent of the world’s irrigated land.
But aquifers around the world are shrinking. A study of 1,700 aquifers in more than 40 countries found that groundwater levels in almost half have fallen since 2000, according to research published in Nature in 2024. The same study found that more than half of the 400 aquifers in the U.S. — including the Memphis Sand Aquifer — are losing water. The Ogallala Aquifer of the Great Plains, the nation’s largest aquifer, which provides about 30 percent of the groundwater used for irrigation in the U.S., is steadily running out of water, the U.S. Geological Survey reported in May.
Hossain grew up in Bangladesh, where villages, farms, and industries are using groundwater faster than it can be replaced. Last year, the government banned groundwater extraction for irrigation and industry in nearly 5,000 villages in northwestern Bangladesh, lined with mango groves and rice paddies.
Villalpando-Vizcaino grew up in Mexico, where aquifers are drying up and cities are sinking. “Mexico City is sinking as much as 10 inches a year, and the city is facing a potential day-zero when the water taps run dry,” he says.
When groundwater levels drop, water pressure drops, too. That can cause compressible layers within and above an aquifer to compact; it can cause land above to subside. Shrinking aquifers in the southwest U.S. have caused cities such as Houston and Phoenix, and the areas around them, to sink by more than a foot. Officials there have had to restrict and even ban the use of groundwater and require cities to use surface water.
That’s also happening in parts of the Mississippi Embayment, especially in eastern Arkansas, which produces half the nation’s rice. The primary aquifer used for agriculture in the embayment is the expansive but relatively shallow Mississippi River Valley Alluvial Aquifer or MRVAA. It isn’t protected by a layer of clay. It sits 20-150 feet underground, stretching out across large areas of Arkansas, Mississippi, and Louisiana, where it supplies about 90 percent of the water used for irrigation.
The MRVAA has fallen to less than 10 percent of capacity in some areas, according to Arkansas state officials. More than twice as much water is being pumped annually from that aquifer as rainfall and other sources put back.
Last spring, the U.S. Army Corps of Engineers broke ground on two projects aimed at reducing depletion of the MRVAA by diverting as much as one billion gallons of water a day from the White River. “These projects will help reduce reliance on dwindling groundwater while also supporting agriculture, increasing municipal water supplies, and boosting economic stability throughout the region,” the Corps said in a statement.
Not everyone agrees. The National Wildlife Federation notes that White River water will be distributed to fewer than a thousand farms in four rural counties through a 650-mile system of pumps, pipelines and canals. “This ill-conceived Grand Prairie Area Demonstration Project — one of several Corps projects proposed to tap the White River — would permanently alter the river’s complex hydrology,” the federation said in a statement. “Reduced river flows would threaten internationally acclaimed wetlands and degrade water quality throughout the river basin.”
Shrinking aquifers can cause other long-term problems. When a well pumps, a “cone of depression” forms around that well. When the well turns off and water levels remain below their original level, potential overuse is indicated. The depressed areas start pulling in “younger” water from nearby rivers, streams, and shallow aquifers that often are contaminated. That’s of particular concern around here.
A 1990 study by the U.S.G.S. found “hydrogeologic windows” — natural gaps or breaches in the thick layer of clay that protects the Memphis Sand Aquifer from contaminants in soil, surface water, and shallow groundwater (the so-called Shallow Aquifer) above it. Subsequent studies indicated there were at least six natural breaches in the clay under Shelby County that could allow contamination to “leak” from shallow groundwater directly into the Memphis Sand.
In 2023, CAESAR staff and graduate students completed a five-year, $5 million study of the aquifer, commissioned by MLGW. The study confirmed seven breaches and identified 35 other suspected breaches.
It also detected “modern water” (water that has been in the aquifer less than 60 years) in six of the seven MLGW wellfields that were studied. MLGW draws aquifer water from 10 wellfields in Shelby County.
Brian Waldron
“The clay is thinner than we thought,” says Brian Waldron, a civil engineer and director of CAESER. “It looks more like Swiss cheese, and the breaches make our water vulnerable to contamination, especially from contaminated water in the Shallow Aquifer.”
The Shallow Aquifer — not to be confused with the much larger MRVAA across the river — isn’t protected by a layer of clay in some areas. It’s near the surface and covers much of Shelby County and West Tennessee along the river and near the surface. “Water from the Shallow Aquifer can leak downward through these breaches and enter the Memphis aquifer,” CAESER reported.
There are approximately 200 known chemical contamination sites across Shelby County. Ten of them are federally recognized Superfund Sites in active remediation. That doesn’t include nearly 1,000 places where underground storage tanks (gas, oil, ink, etc.) have leaked.
“We once thought the Shallow Aquifer was unimportant, but now we believe that it’s a vital factor in the quantity and quality of the Memphis aquifer,” Waldron says.
CAESER is working on a new five-year, $9.75 million aquifer study, funded by the city, state, and MLGW. The goals are to find, measure, monitor, and learn more about all breaches in the protective clay under Shelby County. Staff and students also want to learn more about how water and contaminants move — and how quickly — from the surface into the Shallow Aquifer, and then into the Memphis Sand Aquifer.
“We’re a lot more concerned about water quality than water quantity,” Waldron says.
You can walk on the Memphis Sand. I did it years ago on a canoe trip on the Ghost River, an eight-mile section of the Wolf River that widens into a spooky cypress swamp in western Fayette County.
The swamp is in the Memphis aquifer’s “recharge zone,” a low-lying stretch of West Tennessee and North Mississippi where the Great Sand Box rises to the surface to absorb rainwater and surface water and replenish itself. Early on the trip, the guide had us get out of our canoes and stand ankle-deep in spongy sand deposited here by the sea millions of years ago. I didn’t see the ghost of Elvis, but I was walking on Memphis.
“Amazing, isn’t it?” asks Ward Archer Jr., co-founder of Protect Our Aquifer and a veteran of many outdoor adventures in the Memphis Sand recharge zone. (Editor’s note: Ward Archer, a board member of this magazine’s parent company, did not coerce us, financially or otherwise, into writing this objectively important story.) “You feel like you’re standing on the edge of an ocean you can’t see. Imagine what would happen to all that water if the recharge land was covered with concrete and construction?”
It doesn’t take much imagination. The sweet spot in our aquifer’s recharge zone happens to be in the most rapidly developing parts of Shelby, Fayette, and Haywood counties in West Tennessee, as well as growing parts of Marshall and Benton counties across the Mississippi state line.
Only about one percent of the freshwater in the Great Lakes is replenished each year by rain and snow, runoff from rivers and streams, and groundwater inflows. No one knows exactly how or how quickly our aquifer is being replenished. Scientists are working to find out.
Archer first visited the area more than 30 years ago when he agreed to help raise funds for the Wolf River Conservancy. Larry Smith, the conservancy’s first executive director, took Archer to Baker’s Pond, the largest spring-fed source of the Wolf River — and a prime recharge area for the aquifer. “I baptized Ward in the waters,” Smith jokes. “I told him: I’m doing the Wolf; you’ve got the aquifer.”
Much of the Wolf River basin lies in the aquifer’s recharge zone, meandering more than 100 miles through bottomland hardwood forests, cypress-tupelo swamps, and open marshes before it reaches the Mississippi River in downtown Memphis. The basin is part of the much larger Lower Mississippi River drainage system, once the largest forest and wetland ecosystem in North America. What happened? Civilization happened. Forests were cleared, wetlands drained, streams and rivers straightened, leveed, and dammed to make way for farms, cities, suburbs, and exurbs.
Developers continue to cover thousands of acres of the recharge zone with subdivisions, commercial areas, distribution warehouses, and manufacturing plants. That includes the 3,300-acre, $5.6 billion Ford Blue Oval City complex in Haywood County. The company plans to start assembling gas-powered pickups in 2029 and use more than a million gallons of aquifer water every day in the process.
But company and state officials have been working with Protect Our Aquifer and CAESER to mitigate the impact. The company has pledged to use aquifer water only for human consumption, and to treat wastewater and recycle it back to the factory or pipe it 37 miles into the Mississippi River. The company has developed a wellhead protection program that includes monitoring wells, sealed factory floors, and containment basins to protect local soils and the aquifer.
The company also plans to spend $16 million to restore a nearby stream and several acres of wetlands. West Tennessee’s 200,000 acres of wetlands do not only help recharge the Memphis aquifer. They soak up floodwaters and protect the Mississippi Flyway, a vital migration corridor for 40 percent of North America’s waterfowl and 60 percent of U.S. bird species.
The Wolf River Conservancy has preserved 20,000 acres along that river’s watershed, including 768 acres of wetlands east of Collierville purchased late last year by the conservancy and Ducks Unlimited. But conservation efforts are fighting heavy currents. Last year, developers lobbied state legislators to let landowners drain and fill “isolated wetlands” smaller than an acre in size. That category includes about 80 percent of all wetlands in the area.
Earlier this year, legislators rejected a proposal to fund a complete geologic mapping of West Tennessee groundwater, including “breaches” in the aquifer’s protective clay layer, and the entire 12-county recharge zone. Middle and East Tennessee were mapped with TVA funds decades ago.
Only about one percent of the freshwater in the Great Lakes is replenished each year by rain and snow, runoff from rivers and streams, and groundwater inflows. No one knows exactly how or how quickly our aquifer is being replenished. Scientists are working to find out.
A few miles from the Ghost River, researchers for the U of M and CAESER have been studying the aquifer’s recharge zone along Pinewood Creek, a sandy, spring-fed stream that flows into the Wolf. A few years ago, they reported an astonishing discovery. “Only a small portion” of the 12-county recharge zone quickly recharges the Memphis Sand Aquifer at a meaningful rate.
“For many years, scientists assumed that the entire mapped area of the recharge zone allowed water to flow easily into the aquifer,” they noted. “The majority of actual, efficient recharge occurs in stream valleys and gullies with sandy bottoms rather than across flat, elevated upland terraces.”
Streams and gullies that flow through bottomland forests, swamps, and marshes into the Wolf, Hatchie, and Nonconnah rivers. Streams and gullies and swamps that replenish the Memphis Sand.
“As such, the sustainability of the aquifer ... may be highly sensitive to alteration of land use that affects the access to preferential pathways of recharge,” reported the researchers. They included Waldron, Daniel Larsen, and Scott Schoefernacker.
The Blue Print puts it more bluntly: “Overuse (of the aquifer) coupled with rapid rural development threatens to seal off recharge areas with pavement and rooftops, cutting off the aquifer’s natural lifeline.”
Protect Our Aquifer: Carl Richards, Ward Archer, Sarah Houston, Rheannon Watson, Jim Kovarik.
I admit. I didn’t pay much attention to the aquifer until I started seeing the signs. Around a decade ago, they seemed to pop up everywhere: blue-and-white yard signs bearing a simple yet profoundly important message:
Protect Our Aquifer.
The signs announced the launch of a local nonprofit organization. They also gave us Memphians a wake-up call. It’s our aquifer — and our responsibility.
“We can’t wait for someone else to do this for us,” says Sarah Houston, who became Protect Our Aquifer’s executive director in 2021.
Houston first saw the signs as she and her husband, Patrick, were biking through Memphis in September 2017. The two Texans were on the final leg of an 8,000-mile bicycle trip for “Wander Like Water,” a YouTube channel they created to explore water issues across the U.S.
They stopped in Memphis on their way down the Mississippi to record their 29th episode. They talked to Zach Cook from the U.S. Army Corps of Engineers about the river. They talked to CAESER’s Waldron about the aquifer. “This was at the start of Protect Our Aquifer,” Houston remembers. “I saw the blue yard signs and read all about the campaign against TVA’s wells.”
In 2016, the county health department, which oversees such things, gave TVA a permit to drill five deep wells into the aquifer. TVA wanted to draw millions of gallons of water a day to cool its new $1 billion power plant in southwest Memphis.
The new plant uses natural gas to generate electricity. That’s better for the environment than the coal the old plant had burned — thousands of tons of coal a day, for decades. In the process, the plant produced tons of coal ash, a toxic substance that contains mercury, cadmium, and arsenic. TVA mixed the coal ash with water and dumped it into unlined ponds on their property.
But the coal ash ponds were near at least one major breach in the layer of clay that protects the Memphis Sand from the shallow groundwater above it. “If TVA had used their wells — pumping water constantly right next to the coal ash pits — they would have pulled the arsenic and other contaminants in the coal ash ponds down into our drinking water supply,” Archer explains.
The Tennessee chapter of the Sierra Club had been pushing TVA for years to close the coal-fired plant and clean up the ash ponds, and the group took on the TVA wells. The Sierra Club’s Scott Banbury asked the Shelby County Groundwater Control Board to rescind TVA’s drilling permit. Then he asked Archer to help him raise community awareness and support. Together they hosted a public meeting on the matter in October 2016. “This is the first time ever that the issuance of a water well permit has been appealed,” Banbury told those assembled. “We have no idea what will happen.”
The Groundwater Control Board was established in 1987, a few years after contamination was detected in municipal water wells in South Memphis and Collierville. The board’s stated mission is to “secure, protect, and preserve the quality and quantity of groundwater.” But board members said their hands were tied by weak or nonexistent regulations on well-drilling. They voted 7-0 in favor of TVA.
“We were gobsmacked,” says Jim Kovarik, one of the aquifer advocates who attended the groundwater board’s November 2016 hearing. “We thought everyone wanted to protect the aquifer. When we realized what was happening, we decided to keep at it.” They kept at it by forming Protect Our Aquifer, and Kovarik became the group’s first executive director.
In 2017, TVA reported finding arsenic at 300 times the legal limit in groundwater near the coal ash ponds. The Tennessee Department of Environment and Conservation ordered TVA not to use the new wells and to investigate further. In 2018, TVA reported that a “pump test” of two new wells revealed a “hydraulic connection” between the contaminated shallow groundwater and the Memphis Sand.
Later that year, TVA scrapped plans to use their own wells and started buying aquifer water directly from MLGW, drawing millions of gallons a day. TVA is one of MLGW’s largest water customers. “That still means they’re using aquifer drinking water to cool the power plant,” Kovarik says. “That’s better than using their own wells, but not by much. The more aquifer pumping in that area, the higher likelihood that toxic chemicals will be pulled down into our drinking water supply.”
“Everyone recognizes there is something precious we all share: clean water beneath our feet. Tennessee’s foundational water law is built on this powerful idea, a public trust doctrine declaring that groundwater belongs to all of us. This principle is strongly supported by other state and local laws affirming our right to abundant, clean water.” — The Blue Print
The fight goes on. Under Houston’s leadership, Protect Our Aquifer has kept the pressure on TVA and other large local industries to use treated river water or recycled wastewater rather than aquifer water to cool their plants. The Shelby County Well Code requires that industries — including massive data centers, like Elon Musk’s “Colossus 1” in South Memphis — reuse water for cooling, but the code isn’t enforced. “Enforcing the ban on single-pass cooling water and requiring old and new manufacturing facilities to invest in water efficiency technology will save billions of gallons of aquifer water,” The Blue Print says.
Meanwhile, Protect Our Aquifer continues to grow in size and influence. The organization now has three full-time staffers, including a science director, Schoefernacker, a hydrogeologist recruited from CEASER. They also have four part-time employees and plan to add two more full-time staffers this year.
The nonprofit has trained 35 “Water Warriors,” local citizens who complete a 10-week course on how to advocate for the aquifer. Twenty more people are expected to take the course this fall. The organization has led 17 “Toxic Tours” of local areas where toxic chemicals spilled or buried in the ground have already contaminated the aquifer, or threaten to do so.
Since it took on TVA in 2016, Protect Our Aquifer has continued to battle those threats.
• In 2018, they led a coalition with the Wolf River Conservancy and the Sierra Club to stop construction of a private hazardous waste landfill in a neighborhood along the Wolf River in North Memphis.
• In 2020, they helped to stop two manufacturers in Collierville — Carrier and Smalley-Piper — from injecting treated, though still contaminated, groundwater back into the aquifer.
• In 2021, they joined a coalition to stop construction of a 49-mile crude oil pipeline through South Memphis neighborhoods and a vulnerable aquifer wellfield. The coalition was led by another nonprofit, Memphis Community Against the (Byhalia) Pipeline.
• In 2022, they led another coalition that weakened the state legislature’s attempt to override local laws that block environmentally hazardous projects such as the Byhalia Pipeline.
• In 2022, they worked with NASA to confirm that Ford’s Blue Oval site lies in the Memphis Sand recharge zone. And since 2023, they have led the West TN H2O Delegation, which meets quarterly to discuss Blue Oval’s environmental impact and plan ways to protect the aquifer and nearby streams and wetlands. The delegation includes Ford, MLGW, CAESER, several federal, state and local agencies, and organizations such as the Sierra Club and Ducks Unlimited.
Among other measures, the group is working to build a groundwater monitoring network across West Tennessee. “At this point, it really does not exist except in Shelby County,” Houston says. “How can you manage an aquifer system without knowing how much water you have? It’s like managing your bank account without knowing the balance.”
In 2024, Protect Our Aquifer worked with the Groundwater Board to increase private well permit fees for the first time in nearly four decades. The additional revenue will be used to help the health department test and monitor more than 800 private wells that tap the aquifer.
Since 2024, they’ve been working with other nonprofits to put pressure on SpaceXAI to build a wastewater recycling plant to cool its supercomputer data centers next door to the TVA power plant. (So far, despite promises to the contrary, Musk’s AI company continues to use drinkable aquifer water to cool its data operation in Memphis.)
In 2025, they worked with legislators to protect larger wetlands from development.
Over the years, Protect Our Aquifer has become more than a group of concerned citizens. Staff and board members have attended and recorded every Groundwater Board meeting since the TVA permit hearing in 2016. Houston and Schoefernacker have developed constructive working relationships with the health department’s water quality branch and with members of the Groundwater Board.
“Groundwater is not regulated at the federal level,” says Schoefernacker. “And unlike land use, groundwater use is not overseen by an elected government body. We’ve got to build our own expertise, pay attention to all of the ways in which the aquifer is vulnerable, and work with all interested parties.”
Last spring, Protect Our Aquifer presented to the board The Blue Print, a proposal to create the county’s first groundwater protection plan. When the board was established in 1987, it was charged with creating a “Groundwater Protection Plan” for Shelby County. Almost 40 years later, no plan exists. A new Groundwater Protection Committee is now developing one. The committee includes representatives from Protect Our Aquifer, CAESER, and the health department. They are using The Blue Print as their, well, blueprint.
“We must begin treating and managing the Memphis Sand Aquifer as the foundation of our livelihoods, because it truly is,” says The Blue Print.
As of early August, despite promises to the contrary, SpaceXAI is using an estimated 800,000 to 3 million gallons of Memphis aquifer water every single day. And more data centers are expected. Local industries pay 19 cents per gallon compared to the 32 cents residents pay. That’s hundreds of millions of gallons a year of fresh, cool, clean Memphis Sand water.
It’s raining as I write this. Only four major U.S. cities get rained on more than Memphis each year. When it rains here, it pours, replenishing rivers, streams, lakes, ponds, wetlands, and aquifers. Replenishing — and contaminating.
Water is nature’s solvent. Rainwater rinses manmade toxins — fertilizers, pesticides and herbicides, oil and gas, hard metals, and so on — out of our air, off our streets and parking lots and rooftops, and into our soils, surface water, and groundwater.
Here in Shelby County, rainwater that doesn’t evaporate or isn’t absorbed by soil or plants is directed by roads, curbs, gutters, drains, ditches, culverts, and pipes into the Wolf River or Nonconnah Creek watersheds — which are constantly exchanging water with the Memphis Sand.
“The truth is, we’re all contaminating our drinking water,” Larry Smith says. “The issue is whether we’re going to do what’s necessary to protect the aquifer system that collects, cleans, and filters it naturally and for free. Or whether we’re going to overwhelm and ruin that system and start paying a lot more to do it ourselves.”
Smith was a member of the Blue Stream Task Force, former Memphis Mayor A C Wharton’s short-lived effort to address the three biggest threats to the Memphis Sand Aquifer: Contamination, consumption, and competition. “We have an abundance of water, but it’s not something that’s going to take care of itself,” Wharton told local scientists, environmentalists, engineers, and business and government leaders in 2016. “We have to be vigilant about how we use it and how we protect it. The quantity and the quality.”
The Blue Stream Task Force dried up after Wharton left office in 2017. Legislators talked about establishing a Memphis Sand Aquifer Regional Management Board “for the purpose of managing, conserving, preserving, and protecting the Memphis Sand aquifer, and increasing the recharge of such aquifer while preventing waste or pollution in the aquifer.” It didn’t happen.
“All water problems are local,” the journalist Charles Fishman wrote in The Big Thirst, his brilliant 2011 book. “There is no global water crisis because all water problems are local or regional, and their solutions must be local or regional.”
Memphis has proven that more than once. The deadly Yellow Fever epidemics of the 1870s left Memphis bankrupt, bereft, and thirsty for clean water. Back then, the city’s drinking water came from cisterns, shallow wells, and the Wolf River.
In 1887, Richard C. Graves, who sold ice, drilled a hole 354 feet into the ground along Court Street and struck sand. Memphis Sand. Cold, clean groundwater from the ancient aquifer gushed into the air. The city had a new source of drinking water.
Exactly 100 years later, county officials established the Shelby County Ground Water Quality Control Board “to carry out a comprehensive aquifer protection program.” For the first time, rules and regulations were established to control local access to our aquifer. Nearly 40 years later, it’s still a work in progress.
Shelby County is the only county in Tennessee with the authority to manage its own groundwater. That authority was vested in the Groundwater Board, but most of the responsibility was given to the county health department.
“In the early years it had more to do with protecting the aquifer from illegal wells that could poison the water,” says Claudia Haltom, the former Juvenile Court magistrate. Haltom, then a county attorney, and Helyn Keith, the health department’s attorney, wrote the original legislation. “Anybody digging a well without a permit was to be prosecuted. That discouraged the well-diggers from this. When wells were illegally dug, the county made the owner plug the well. It was a tightly enforced violation. Keeping the aquifer safe and clean was always a concern.”
It still is. The health department’s five-person Water Quality Branch and Septic Tank Program water quality branch is charged with the daily enforcement of the Shelby County Well Construction Code. That includes issuing permits for all wells not owned and operated by MLGW and other local utilities. Well permits are automatically denied for Class A wells “designed to withdraw 250 gallons per minute or more from the aquifer.”
The Groundwater Board hears the appeals. But the board’s 11 appointed members meet only four times a year. “The Groundwater Board has broad authority to create groundwater protection programs that would be funded and carried out through the health department, although they have primarily convened to hear appeals regarding well permits,” says The Blue Print.
The Blue Print wants to empower the Groundwater Board and beef up the health department’s water code enforcement. The board’s new Groundwater Protection Committee is focusing on three priorities:
1. Digitizing the health department’s more than 60,000 pages of paper records on all private wells and septic systems.
2. Developing a countywide wellhead protection program that regulates land use and drilling around all wellheads, contamination sites, and recharge areas.
3. Establishing a countywide monitoring well program that provides regular, consistent, and widespread monitoring and sampling of water quality in the more than 800 non-municipal wells.
The Blue Print says the need for a comprehensive Groundwater Protection Plan is obvious.
“Everyone recognizes there is something precious we all share: clean water beneath our feet,” says The Blue Print. “Tennessee’s foundational water law is built on this powerful idea, a public trust doctrine declaring that groundwater belongs to all of us. This principle is strongly supported by other state and local laws affirming our right to abundant, clean water.”
David Waters is a longtime Memphis journalist and associate director emeritus for the Institute for Public Service Reporting at the University of Memphis.
