1/2/08

The Great Lakes: An Important Drop in the World’s Water Bucket

Right now in the Great Lakes region we are very focused on protecting our lakes from serious water loss. In today’s Milwaukee Journal Sentinel, reporter Dan Egan wrote about the near record drop in water levels in the Great Lakes. We are working hard to get the Great Lakes water Compact approved in Wisconsin in order to stop the imminent grabs for these waters from around the world. While our attention is appropriately directed at this patch of surface water hunkered down in the eastern part of the great North American continent, it is helpful to see the Great Lakes in the larger frame of fresh and seawater throughout the world. Doing so makes the argument for a Great Lakes Compact even stronger.

We all know that 97% of the world’s water is salty. Most of the remaining fresh water—in fact, 80% of it—is locked in the world’s glaciers, the majority of which reside in the Antarctic region. According to geologist John Renton of West Virginia University, the other 20% of fresh water lies under the earth’s top layer as ground water. Consequently, the earth’s surface water makes up a mere fraction (less than 1%) of the fresh water on planet earth. Although we like to state that the Great Lakes hold 20% of the world’s fresh surface water, in relation to the amount of fresh water held in glaciers and underground, it is but a few drops in the world’s bucket.

When we look at the world’s water, here’s what we see. The oceans are becoming more acidic as they absorb greater amounts of carbon dioxide, methane and other greenhouse gases. The oceans capture 22 tons of carbon dioxide a day. By century’s end they could be 150% more acidic than at the beginning of the Industrial Revolution (Les Blumenthal, Milwaukee Journal Sentinel, Dec. 23, 2007). That would pretty well take life out of the oceans.

Next we see the glaciers, the world’s main reservoir of fresh water. The vast majority are shrinking faster than scientists predicted. The fast melting ice races down to meet the sea and turns to salt water. Or it rushes through rivers faster and with more power than the river beds can manage, flooding the land around until it also reaches the seas. “Mt. Kilimanjaro, Africa’s tallest mountain, has lost 33% of its ice field between 1989 and 2000,” according to Lester R. Brown of the Earth Policy Institute. The entire snowcap could disappear by 2015. Scientists are predicting that South American glaciers could disappear in 15 years. In the United States the snow pack in the Rocky Mountains that feeds the great western rivers—the Columbia, the Sacramento, and the Colorado—is projected to shrink 70% by 2050. Much of the west relies on running water from those major rivers.

From the glaciers we look at ground water. In the United States we take about 40% of our fresh water from ground water, and about half the states mine at least half their water from ground water. In the U.S. ground water supplies 50% of all water used for drinking; 40% of water used in irrigation and crop growth; and 25% of water demands for industry. According to Will Hoyer of Clean Wisconsin, approximately 70% of Wisconsin residents and more than nine out of ten Wisconsin communities depend on ground water for drinking water.

But the aquifers that hold and clean our fresh water are running low. The water tables of the 20 largest aquifers in the U.S. are no longer recharged sufficiently and at present rates will eventually run dry. The Department of Agriculture reported that in parts of Texas, Oklahoma, and Kansas—leading grain-producing states—the underground water table has dropped by more than 100 feet (Lester Brown, Plan B 3.0).

Around the world ground water tables are falling as fast or faster than in the U.S. In China, India and the middle East, along with major portions of Africa, drought conditions and overpumping of aquifers has led to dramatic depletion of ground water, and as a result, an alarming reduction in the production of grains and wheat. Fred Pierce reported in the New Scientist that “half of India’s traditional hand-dug wells and millions of shallower tube wells have already dried up, bringing a spate of suicides among those who rely on them. Electricity blackouts are reaching epidemic proportions in states where half of the electricity is used to pump water from depths of up to a kilometer.”

We are running out of fresh water around the world. From the rapidly melting glaciers to the more deeply buried, increasingly toxic ground water to the fragile and often polluted surface water of our lakes and streams, we see once fertile land turning to deserts, lakes transforming into hollowed out fields, and majestic snow-capped mountains dripping into subdued hills. Here in Wisconsin, we have a very small, threatened share of the available fresh water left on the planet. We need our legislatures to step up now and put some controls on the use of that water.

But more than that, as a world community we urgently need to conserve the remaining water we have and finding ways to use it more efficiently. “Efficiency” has been called the most powerful conservation tool in our toolkit. Conservation and efficient use of ground water, as well as surface water, needs to become a state-wide priority for the citizens and governing bodies of all Wisconsin communities.

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Related Web Site Links:

Sierra Club

Great Waters Group