SULLIVAN COUNTY, NY — Our home used to get all its water from a spring that had run steadily since at least the late 19th century. The water was crystal clear and delicious, and worked even when the power was out. 

But it turned out the water was finite. When people moved into our neighborhood and began building homes and digging wells after 2001, the spring started drying up along with the new draw on the water table. 

We were lucky and could afford, eventually, to get a well. But the lessons we learned in the meantime about water ran deep.

This is a simplified diagram showing how the ground is saturated below the water table (the solid blue area at the bottom). The ground above the water table (the pink area) might be wet to a certain degree, but it does not stay saturated. The dirt and rock in this unsaturated zone contain air and some water and support the vegetation on the Earth. The saturated zone below the water table has water that fills the tiny spaces (pores) between rock particles and the cracks (fractures) in the rocks.

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What is groundwater? 

Groundwater is part of the water cycle. Rain falls and hits the ground, then “percolates down to the water table, which is a conceptual surface existing everywhere at some depth below the land surface,” write Eileen Poeter et al. in “Groundwater in Our Water Cycle,” a book published by the Groundwater Project. “The depth of the water table varies from location to location.”

Apologies to geologists, but: The earth’s bedrock is composed of hard rocks, such as granite, and more porous rocks, such as limestone. When the water makes its way through the top layer of planet (yes, think of drip coffee), in many places it hits limestone, which dissolves in water. Underneath that, further down, can be some of the hard rock or clay, and then the water stops. (Like your mug, if we’re going to keep the coffee analogy going.) So the water pools on top of that impermeable layer and moves sideways (not like your mug), and you have an aquifer.

That pooled water might stay underground but often it heads for rivers or oozes out of the land in springs or otherwise. Plants absorb water from the top layer of earth and send the water into the atmosphere; bodies of surface water send some there too. And then it comes back down and the cycle continues.

Seventy to 75 percent of water ends up going through the cycle, explains the Groundwater Project—and only 25 to 30 percent does not.

Half of that is our groundwater. 

Groundwater drawdown

“When we talk about water being a finite resource that is constantly under stress, we have to understand that it is pretty much an unregulated resource,” said Barbara Lerner in recent remarks at a Bethel Town Board meeting. 

We tap into the groundwater with our wells. Forty-three million people—most in rural areas—use wells for their water. Hydrologists estimate, according to the National Geographic Society and the National Ground Water Association, that under the U.S. is at least 33,000 trillion gallons of groundwater. 

It’s estimated that the U.S. as a whole, for all purposes, uses 82.3 billion gallons per day of fresh groundwater. (To learn where it’s going, see “Water use,” page 15.) 

But it’s harder to guess how much each family with a well uses, since there is no water-usage tracker on a well and few regulations. The issue is complicated further when formerly urban residents, new to wells, don’t realize that they need to watch how much water they use.

The first sign that there’s a problem can be issues with your own well or that of your neighbor. (See sidebar, “Is the well going dry?” page 15.)

When you pump water from your well, that “lowers water levels near the well, causing water to flow out of storage and toward the well,” write Poeter et al. “This lowers water levels farther from the well, creating a cone-shaped water level surface around the well… known as a cone of depression or a drawdown cone.” 

Cones of depression, the PA Department of Environmental Protection, notes, can change the way water flows, which can change what you find in your well water. If “a well owner pumps water out faster than it can be replaced, the water table will drop and the well might run dry temporarily.”

Using a great deal of water isn’t just about possibly reducing your neighbor’s supply, it’s about increasing your chance of getting something you don’t want in your water. Incidentally, private “well owners are responsible for delivering safe drinking water to their households,” notes the federal Environmental Protection Agency. “The quality and safety of drinking water from private domestic wells are not regulated by the federal government under the Safe Drinking Water Act, nor by most state governments and laws.”

In other words, wells aren’t regularly, officially monitored for quality, although states (including in the region) provide important information for well owners online. See links below.

How full is the aquifer?

It’s also hard to estimate how many gallons an individual aquifer contains. Estimates are often rough, the Groundwater Projected noted. 

Groundwater levels can be measured from wells, but even then, it’s possible that the wells draw from other water sources too.

What is known is that an aquifer can be severely depleted. Witness the Ogallala Aquifer in Kansas: it is an important water source for western and central Kansas, and heavy use by large-scale agriculture has reduced the amount of water available. The aquifer isn’t replenishing itself fast enough. In 2023, the Kansas legislature allocated $35 million to deal with the crisis.

Replenishment

Groundwater can be depleted, but it can also be replenished. It can be redirected or injected into the aquifer. Recharge basins can be filled. Water can be paid for and trucked in. Sometimes a community or well owner waits for several long, soaking rains. It’s not always an easy process, nor is it cheap.

If the amount available is difficult to measure, if the amount used by residents isn’t metered, how do we know when the well is about to run dry? 

As “Groundwater in Our Water Cycle” points out, “The need for understanding our groundwater systems and for managing them in a thoughtful manner within the constraints of the hydrologic cycle is greater than ever.”

Water use

When it comes to industry, the most water is consumed by large-scale agriculture, including meat production, can use a lot of water. Take for example farms in California, Arizona and the Midwest. 

Other water-sucking businesses or industries: Nuclear power plants and other energy producers, fashion and textiles (which includes agriculture), cooling centers for technology, and beverage production—which again includes agriculture. 

But what about people? The federal Environmental Protestion Agency estimates total water use by an individual at 100 gallons per day. Not all of that needs to be safe drinking water—some is for showers or for flushing toilets. (The toilet alone can use 27 percent of the total, the agency adds.)

In 2011, New York State updated the Water Resources Law to require permits for any project with a capacity to withdraw 100,000 gallons of water per day from surface water or groundwater. (There are exceptions, such as for firefighting.) 

But that’s decided early on, before anyone moves in. The NYS Department of Health estimates water demand at 110 gallons per day per bedroom, but “this number, however, does not take into account extra water needed for homes with high occupancy, lawn irrigation, spa tubs, and other activities and plumbing fixtures that have a high water demand. Higher water use activities and fixtures are not recommended for homes served by low yield wells,” the state added.

Is the well going dry?

A low well is a serious problem. Here are some water issues to watch out for. If you’re concerned, you should call your well contractor; sometimes the problem is just the pump or the piping. And sometimes it’s more significant.

Sputtering water

Sputtering or spitting in a faucet can happen when air is pulled into the water line.

Low pressure

This could be gradual, or there could be a sudden drop in pressure. 

Noisy pump

Is the pump working harder than it normally does? Does it run all the time, or sound different? If the water level in the well is low, then the pump has to work harder.

Water quality changes

Water coming from a drying well can look dirty, full of sediment. The water might also taste or smell different. This happens when the pump pulls up sediment from the bottom of the well.