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Communications > Sustainability Plus > Posts > Expert: Alabama’s Groundwater Abundant but Still Finite

Few regions of the world are as different as China and Alabama, and perhaps nowhere is that difference more starkly expressed than in groundwater conditions.

China, a nation with 20 percent of the world's population and only 5 to 7 percent of its freshwater resources, is facing nothing less than a groundwater crisis.

Perhaps nowhere else in the country is this crisis more acute than in the county of Yongji in the Shanxi province of northern China.

The lush green fields planted in maize and fruit trees belie the breaking point that awaits this farming region in only a few decades, says Matt Curell, an Australian groundwater expert and Monash University doctoral student who visited the region recently.

All of this bounty comes from a finite source, groundwater, the levels of which have been dropping at a rate of almost 3 meters a year throughout much of the province since 1986. Meanwhile, the rate of natural recharge via rainwater is running as low as a few millimeters a year, far less water than what is being extracted, Curell stresses.

Overapplication of fertilizers is seriously compromising the quality of much of the remaining groundwater, which is also affected by natural enrichment of fluoride and arsenic.

The crisis isn't limited only to Shanxi province. Water already is scarce in two-thirds of China's 660 cities — a scarcity that will grow worse as China's population and economic growth intensifies. According to estimates by China's Ministry of Water Resources, the country will consume some 750 billion cubic meters of water by 2030, roughly 90 percent of the total supply of usable water resources in the country.

Approximately 70 percent of freshwater resources in China are employed in agriculture — a reality that ultimately will require tough decisions in the future.

"China may want to rethink its food security issues because the current strategy is completely unsustainable," says Bridget Scanlon, a hydrologist at the University of Texas in Austin.

Meanwhile, conditions in Alabama couldn't be more different, says one water resources expert.

"We are lucky," says Dr. Eve Brantley, water resources program coordinator for the Alabama Cooperative Extension System and Auburn University assistant professor of agronomy and soils.

She cites the Geological Survey of Alabama, which estimates that the state possesses some 553 trillion gallons of freshwater underground located in 20 aquifers throughout the state.

Despite the almost stupefying abundant quantity of groundwater in the state, Brantley says there is still work to do.

Alabama is undergoing its own spurt of population and economic growth, and while groundwater supplies remain plentiful, Brantley says it still behooves the state leaders as well as citizens to manage these resources as a finite source.

She points to the Dothan region of the state where heightened demand for public water and agricultural use has resulted in some depletion of groundwater.

"We've got to make sure that when we drop a well to address heightened demand for water that we assess water supply and follow it with a question: will we end up pumping more than we recharge?"

Brantley says Alabama's abundant rainfall — an average 55 inches a year — has resulted in many Alabamians taking groundwater recharge for granted. As it happens, only about 6 inches of this rainwater eventually recharges aquifers.

Much of the rest washes off the landscape surfaces and ultimately ends up in the Gulf of Mexico.

"It's important to note that rain that falls on asphalt and concrete doesn't have the opportunity to soak into the soil," Brantley says, adding that "the more we pave Alabama, the more water we're going to export into the Gulf of Mexico."

Even in a water-rich state such as Alabama, Brantley and other water quality experts are encouraging cities and towns throughout the state to adopt more permeable surfaces to ensure that more of this rainwater trickles back to groundwater resources.

Likewise, she and her colleagues are also encouraging homeowners to adopt practices such as using rainwater cisterns and rain gardens to make effective use of rainwater.

Add to that the threat that nonpoint source pollution — pollution that comes from different sources — poses to many of the state's aquifers that have rapid recharge, such as the Trussville area.

"The recharge in these areas is so quick, and when it rains we have to be mindful of possible sources of nonpoint source pollution," Brantley says.

Brantley sees her role as helping Alabama's municipal leaders and homeowners understand how all of these practices work in tandem to safeguard the state's abundant, but finite, water resources.

"It's all connected," she says. "It's all a matter of good planning and wise use."