What Is A Drought?

A drought is simply a long period (usually a season or more) of dry weather where less than normal or no precipitation falls. Precipitation is any form of moisture such as rain, snow, sleet, etc. Droughts are a natural and frequent occurrence in the Delaware River Basin (the basin contains 13,539 square miles and drains portions of Delaware, New Jersey, New York, and Pennsylvania). How bad a drought is usually depends on how little precipitation falls, how long the drought lasts, and the size of the area that is affected. The next time you hear someone talk about a drought where you live, play detective and look for some of the many signs that may be telling you the lack of precipitation is taking its toll:

LOW WATER IN STREAMS, RIVERS, LAKES, AND PONDS - While visiting your favorite park, you may have noticed how little water you found in the rivers, streams, lakes and ponds. Low flow in water bodies may be one sign of drought. Water levels fall when there is not enough precipitation to replenish water evaporated from streams and other bodies of water. For example, when it rains, water bodies may be replenished by surface water runoff (the water running downhill into lakes, streams, etc.) or by ground water (water that has seeped into the ground and created a saturated layer of soil). Ground water is the reason why some bodies of water can remain flowing during long periods without precipitation. (If you would like to learn more about ground water and rivers/streams, go to the United States Geological Survey's (USGS) Water Science for Schools web pages.)

DECLINES IN WATER LEVELS IN WELLS - You may be watching the news or listening to the radio and hear about concerns over wells becoming depleted and unusable. Wells get their water from aquifers. An aquifer is simply a geologic formation that stores and transmits ground water. Aquifers are recharged as precipitation is absorbed into the soil. With little or no precipitation to replenish the ground water lost through use, water levels in a well may be significantly lowered. During especially dry periods of heavy use, some wells may completely dry up. Water levels in a well also may drop due to heavy use of nearby wells that depend on the same aquifer.

DRIED-OUT, BROWNING VEGETATION AND EARLY LEAF LOSS - During especially dry summer months, you may notice farm fields turning brown and trees dropping their leaves. The grass on your front lawn may turn brown and lifeless looking. Every living thing needs water to survive. This includes trees and the plants found in farm fields, pastures, home gardens, and meadows. The stress of drought causes soil to dry out. With little or no moisture to replace what is lost through the growing process, plants wilt and begin to turn brown. Some plants, such as the grass outside your home, may attempt to survive the drought by becoming dormant (a period of inactivity, slow or no growth). Unfortunately, if relief in the form of rain does not happen soon enough, many crops and other plants are lost to the dry conditions.

Many trees and shrubs respond to drought conditions through an early dormancy. To do this, trees and shrubs drop their leaves earlier in the season than normal. Leaf drop is a tree's survival tactic to reduce the amount of water that otherwise might have been lost through the leaf surface by a process known as transpiration. Despite this tactic, many trees and shrubs die during droughts, or are so weakened by the dry conditions that they may die the following growing season after a drought. (See "What About Plants and Wildlife During A Drought" for more information.)

Physical signs of a drought can be very alarming. Many people take abundance of water for granted and only in its absence do we realize just how important it is to every living thing on the planet. During a drought, it is very important that everyone does their best to conserve water. Of course, it shouldn't take a drought to make people conserve water. Water is such an important resource and water conservation should be practiced every day of our lives. Water conservation consists of eliminating wasteful practices of water use, such as allowing a faucet to drip, toilets to leak, or taking baths instead of showers. See "What You Can Do to Save Water During A Drought" for more tips on how you and your family can save water each and every day.