kw: book reviews, nonfiction, textbooks, water, hydrology
I have been saying since the 1980s that the wars of the 21st Century will be fought over water. Similar, and quite definite statements are found in the last chapter of a 634-page text, Groundwater for the 21st Century: A Primer for Citizens of Planet Earth by John A. Conners. But water wars are not his focus, knowledge is. The aim of Dr. Conners is to educate the populace, the "Citizens" of his title. 'Tis a pity none can similarly educate national and business leaders whose focus is the next election or quarterly profit/loss statement.
Though the author claims the book was not written as a textbook, it is one. In fourteen chapters it covers the field of groundwater science quite thoroughly at a layman's level, if you don't mind an occasional equation and a little chemistry here and there. Though I spent the past week reading the book, I'd have taken twice as long had I not been able to skim much of the material.
What is groundwater? Simply put, it is all the water beneath our feet. In most parts of America, particularly the rainy East and Southeast, you can dig a foot or two down and see water seep into the hole. That is groundwater trickling out into view.
How much is there? A lot, but the rub is, there are a lot of us and we use a lot of water. At this point, I'll take a brief aside: Units are used quite inconsistently throughout the book. Sometimes we find square miles or cubic miles, and at others square or cubic kilometers. Sometimes a volume is in gallons, then in liters, and larger amounts may be in acre-feet or cubic whatever. Sometimes a conversion between Metric and (mainly) English units is given, sometimes not. Here I will use SI (the "official" Metric set of units, out of 3 flavors of Metric), and convert when necessary. So again, there is a lot of water, but there are billions of us, and the more affluent we are, the more water we use. On average, and American wastes an amount of water weekly that is equal to the entire water budget of a person in a Third World country, for a year.
How is it being used? From quite well to quite abominably. In the rich West we take it for granted unless it is our job to worry about it. This is not always wise. I once lived on a hill high above a flood plain. On this flood plain there were several mobile home communities. The typical setup was this: each trailer/manufactured home sat on about a half acre of ground. In the front yard near each house was a water well. On a flood plain the water table, which is the upper limit of groundwater connected to the nearby river, is at a depth of several feet, so the wells were shallow. Guess what was in every back yard? A septic tank and outflow field. The tank and piping were typically set shallower than the water table, meaning that whatever came out the pipes tricked down into the groundwater. I wonder if anyone living there ever considered that they were drinking their own slightly filtered toilet waste...and their neighbors'!
Most groundwater is extracted for agricultural use. At one point, we find that the minimum requirement of water needed to produce one day's food is about 3,000 liters. You only need a few liters to drink, and a few more to sponge bathe and to clean eating utensils. Depending on what we eat, our agricultural water use can be even higher. It takes 200 liters to produce one hen's egg, more than 15,000 l per kg of beef and 1/3 of that per kg of chicken meat. On the herbivory side, an apple tree consumes 125 l per apple, it takes more than 1,800 l to grow 1 kg of wheat, and once the wheat is milled and made into bread, each slice has 60 l of water use hidden within.
In addition to overt and semi-overt water consumption, a hidden "consumption" of water is contamination and pollution. To pollute water is to render it unusable, or at the very least, risky to use. I once heard a European water policy expert discuss laws—I don't know if they are on the books or only proposed—that mandate every manufacturing plant that wishes to release "used" water into a waterway, must put the outfall upstream of its own inlet. That supposedly gives them incentive to clean the water up before releasing it. But it doesn't address whether a company might do only partial cleanup of effluent, and more thorough cleanup of water it is using, only as needed on a process-by-process basis. A clever enough company might still pollute, but at lower cost than thoroughly cleaning their effluent. So I'd go further. I favor a law requiring that every executive and manager and salaried employee be required to live in a dwelling that has its water supply hooked up directly to the outflow from the plant: to drink the water, to cook with it, to shower or bathe with it, to wash their clothes and water their lawns and gardens with it.
OK, you say, "Dream on, dude!" Yeah, I know. The powerful always find ways to circumvent everything. That's why we need occasional revolutions.
Back to the book. In it we find that we are not using groundwater as fast as it is formed. The trouble is, groundwater varies in its purity and accessibility and in the cost to retrieve and transport it. The "cheapest" groundwater is mainly in underground formations, called aquifers, that are not being replenished very fast. In most of the world, we are extracting water that won't be replaced. It is called water mining. Only once it is gone will we turn to more costly water, and maybe one day we'll learn to use the water that is being replaced the most rapidly. But, give us time, and we'll find a way to outstrip even that supply. We need, not more water, but wiser water use. In the usual case, we do only what we are forced to do. This will most likely continue.
The book has no call to action. It is entirely educational. People need to understand what is actually out there, and what is actually going on. The learning itself will trigger action. That is the author's hope.
Tuesday, February 17, 2015
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