Which of the following do you think contains the greatest proportion of water? A watermelon, a glass of milk, a ripe tomato, or your next-door neighbor?
If you guessed a watermelon, you’re wrong. According to the people who measure these things, a ripe tomato contains between 93 percent and 95 percent water, while a watermelon comes in second at 92 percent. A glass of milk consists of 87 percent water, while the human body is made up of just 61.8 percent water — though our brains are 75 percent water.
More precious than gold and more common than dirt, water covers nearly 71 percent of Earth’s surface. But before you turn on the hose, remember that only about 3 percent of all the water on our planet is freshwater, and just 0.6 percent of that is available as surface water in lakes, rivers and streams. About 2.4 percent of Earth’s freshwater is solid, locked into glaciers and the polar icecaps, while 1.6 percent of our freshwater reserves lie in underground aquifers.
Whether you raise a vegetable garden, an orchard, field crops or livestock, you know it takes water — and lots of it — before the fruits of your labor reach the dinner table. In fact, agriculture leads the world in freshwater consumption, with about 60 percent of all freshwater use going toward agricultural irrigation.
Facts about water for the farm
Unless you raise pineapples, which consist of 80 percent water, in the shadow of Mount Waialeale on the Hawaiian island of Kauai — the wettest or second wettest place on Earth, with 460 inches of annual rainfall — you likely know something about the importance of giving your garden a timely watering.
Depending on your soil type and climate, a tomato plant needs about 16 inches of water per season, or about 2 quarts of water per plant per day, to reach maturity. Potatoes generally require between 18 and 20 inches of water, while it takes as much as 20 to 25 inches of water during the growing season to produce a ripe watermelon. A pecan orchard in the arid southwest requires between 60 and 72 inches of water per season, and if you’re a Midwestern corn farmer, you’ll need 23 to 24 inches of water to harvest a 200-bushel corn crop.
Keeping your garden watered may not be a problem if you live in the southeastern United States. Areas of Alabama, Florida and Louisiana receive more than 60 inches of annual precipitation. If you live in one of the 17 western states, however, timely rains can be as scarce as hen’s teeth. Not surprisingly, Nevada, which receives just 9.5 inches of annual precipitation, is the driest state in the nation, followed by Utah, Wyoming and Arizona.
The driest portions of the High Plains, which covers parts of eight states from the Dakotas south to Texas, receive as little as 12 to 15 inches of annual precipitation. Northeastern Colorado, for example, averages about 15 inches of annual precipitation. Farmers there who supply the area’s fast-growing dairy industry need more than 30 inches of water per season to produce alfalfa, and about 22 inches of moisture to raise corn silage. Fifty years ago, these farmers would have relied on flood or furrow irrigation, but this method loses much of the water to evaporation. Today, many farmers have switched to more water-efficient, low-pressure center-pivot sprinklers and drip irrigation systems to conserve precious water resources.
Drinking water for your critters
How much water will you need if you raise livestock? Dairy cows require more water than any other farm animal, drinking between 25 and 50 gallons of water per day. Experts at North Dakota State University (NDSU) say a 200-pound feeder pig consumes an average of 2.5 gallons of water per day, and a feeder lamb requires about 1.5 gallons of water. A working horse can drink between 12 and 18 gallons of water per day, while a 1,200-pound steer needs between 9 and 22 gallons daily.
Chickens, on the other hand, tend to be sippers rather than gulpers. NDSU experts say a flock of 1,000 laying hens will consume between 40 and 80 gallons of fresh water daily, with each laying bird drinking about 25 percent of her daily water intake during the two hours prior to darkness. And speaking of laying hens, did you know a fresh egg contains about 65 percent water?
Human water consumption
We humans, by comparison, need around 64 ounces of water daily to remain healthy and to avoid dehydration. That adds up to eight 8-ounce glasses of water per day, although about 20 percent of that can come from the foods we eat, and some comes from coffee, juices and other liquids we consume.
But that’s just the start of our water consumption. The American Water Works Association says the average person uses 1,383 gallons of water per day. We use 2 to 7 gallons of water to flush a toilet, 25 to 50 gallons to take a five-minute shower, 9 to 12 gallons to run a dishwasher, and 2 gallons just to brush our teeth.
And just where does our water come from? If you live in the country, you may be among the 17 million American households that use private wells for their water supply. The rest of us, of course, depend on water supplied by one of the 56,000 community public water systems in the United States.
Read more: Keep your garden healthy with these tips.
Jerry Schleicher is a freelance writer from Parkville, Missouri, who learned to set siphon tubes on an irrigated farm in western Nebraska.