About Groundwater
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Groundwater is the water that soaks into the soil from rain or other precipitation and moves downward to fill cracks and other openings in beds of rocks and sand. It is, therefore, a renewable resource, although renewal rates vary greatly according to environmental conditions.
It also is an abundant natural resource.
Of all the freshwater in the world (excluding polar ice caps), 95 percent is groundwater. Surface water (lakes and rivers) only make up three percent of our freshwater.
Groundwater provides much of the flow of many streams, lakes and rivers. Groundwater adds 492 billion gallons per day to U.S. surface water bodies. In large part, the flow in a stream represents water that has flowed from the ground into the stream channel.
Scientists estimate U.S. groundwater reserves to be at least 33,000 trillion gallons — equal to the amount discharged into the Gulf of Mexico by the Mississippi River in the past 200 years.
The United States uses 79.6 billion gallons per day of fresh groundwater for public supply, private supply, irrigation, livestock, manufacturing, mining, thermoelectric power, and other purposes.
Groundwater is tapped through wells placed in water-bearing soils and rocks beneath the surface of the Earth. There are nearly 15.9 million of these wells serving households, cities, business, and agriculture every day. Wells are constructed by the 8,100 contracting firms employing nearly 45,000 people dedicated to providing and protecting our nation's groundwater supplies.
Irrigation accounts for the largest use of groundwater in the United States, about 67.2 percent of all the groundwater pumped each day. Some 53.5 billion gallons of groundwater are used daily for agricultural irrigation from more than 407,913 wells. Irrigation is a major reason for the abundance of fresh produce and grains that we all enjoy.
One ton of groundwater used by industry generates an estimated $14,000 worth of output.
These facts help us connect with the important role we each play as stewards, or protectors, of groundwater. Man can adversely affect the resource. Fortunately, there are simple steps that will help protect groundwater and the wells systems that distribute it.These tips and more are available from sources such as a state groundwater or water well association, NGWA, or from your county agricultural extension agent or state government agency with responsibility for groundwater. A convenient source for a broader understanding of our groundwater protector role can be found at www.wellowner.org, a Web service of NGWA.
National Groundwater Awareness Week is not a celebration such as the Fourth of July has become. Instead, we should use the week to reflect more deeply on groundwater's value and its contributions to our lives.
Always use licensed or certified water well drillers and pump installers when a well is constructed or serviced, or when the pump is installed or serviced.
Keep hazardous materials away from any well. Never dump such materials, motor oil, or anything else that could impact water quality onto the land surface, into a hole or pit, or into a surface water supply.