With the continuing rise in world population comes more energy needs, meaning ever-more demand on water resources. That‚Äôs the message coming out of World Water Day (March 22), a day created by the United Nations to build awareness of a range of water issues.
This year the UN campaign for World Water Day focuses on the nexus of water and energy. Alarming statistics come out of this intersection that should give us all pause as to the growth track of humanity.
By 2035, global energy demand is expected to increase by one-third. Producing energy requires lots of water. Fossil fuel production uses large amounts of water and contaminates an estimated 15 to 18 billion cubic meters of freshwater resources each year. Put in more accessible terms, to make one gallon of gasoline, 3 to 6 gallons of water are needed. Even large solar arrays need water; to achieve maximum efficiency, they need to be kept clean.
In the U.S., steam is used to generate 90 percent of our electricity from thermoelectric power plants that use coal, nuclear, natural gas and oil. It takes almost a gallon of water for every kilowatt of energy, and Americans actually use more water running lights and appliances than running their faucets. But energy is required too to run those faucets; it‚Äôs needed to pump water to users and treat it after it‚Äôs used.
Through its energy consumption, a U.S. family of four uses approximately 400 gallons of water daily, enough to fill a bathtub seven times.
Energy and agriculture are the biggest users of water in the U.S., but pause to think why. All that output is going to keep our laptops and iPhones powered, our houses warmed or cooled, refrigerators humming, and keep us fed and watered. U.S. population currently is nearing 318 million. Depending on assumptions of low or high immigration, by 2050 the country might have as many as 450 million people ‚Äî only through zero net immigration would we stay near today‚Äôs numbers. Multiply that 400 gallons of daily water use for a family of four by the additional population growth expected by 2050, and you get a very big number.
Worldwide, continuing, aggressive growth is increasingly stressing our ground water. Many countries are extracting water faster than it can be replaced ‚Äî China by 25 percent, India by 56 percent. In the U.S., the Ogallala Aquifer of the Great Plains provides about 30 percent of the ground water used for irrigation in the country and also provides drinking water for several million people. Parts of the aquifer now are empty, and water depletion is accelerating. It‚Äôs estimated that it would take 100,000 years to replenish the aquifer through rainfall. The current natural recharge rate is very slow, and it‚Äôs believed that much of Ogallala Aquifer‚Äôs water was from the last ice age.
Water use has been growing at more than twice the population increase in the last century. Today, 700 million people live in water-stressed countries, and by 2025, two thirds of the world population could be under water stress conditions. A lot of those people will be looking for ways to escape their situations for what they perceive to be more hospitable places.
Overwhelmed by the numbers yet? Wait, there are more.
An estimated 2.5 billion people live without basic sanitation; 1.1 billion live without clean drinking water; 1.3 billion live without electricity, and 1.02 billion are hungry. Today, 70 percent of the global water withdrawals go to agriculture. With world population, now at 7 billion people, expected to rise to 9 billion in 2050, we will need to increase food production globally by 60 percent, which will require more water.
To frame that last one differently, between now and 2050, we‚Äôre going to have to produce more food than we did in the last 8,000 years.
The gist of the messaging for the United Nations-sponsored awareness event is to move away from inefficient energy production and traditional crop irrigation methods, and to stop over-extraction of groundwater. Those all are things that should be pursued, but will be insufficient if we don‚Äôt get growth under control.
Maria Fotopoulos is a senior writing fellow for Californians for Population Stabilization (capsweb.org). Contact her at email@example.com.