In the spring of 2012, I wrote a five-part series on water (Part I, II, III, IV, V). Part IV, When the Well Runs Dry, discussed human society’s dependence on the unsustainable extraction of water from underground aquifers, with a particular focus on the Ogallala aquifer which supplies the vast majority of water used for agriculture and human consumption in the Great Plains of the American west.
Here is the section on the Ogallala aquifer from my earlier column:
The Ogallala aquifer, which spans the eight states which make up the Great Plains from South Dakota to Texas, is a compelling example of the unsustainability of overpumping an aquifer. It was formed about 12,000 years ago during the end of the last ice age and contains water from melted glaciers. The extraction of water from formations like these is often referred to as the mining of “fossil water.” The Great Plains were largely desolate and unpopulated before the exploitation of the Ogallala for irrigation. Once we started exploiting the Ogallala, the Great Plains were converted into an agricultural belt of wheat, corn, soybeans, and cattle. It’s difficult to overstate the importance of irrigation to agricultural production. The 20% of the farmland around the world that is irrigated produces approximately 80% of our food. In addition to driving agricultural production in the Great Plains, the Ogallala provides 82% of all of the drinking water in that part of the country.
The replenishment of the Ogallala from surface water is quite slow, with only 10% of current extraction rates being replaced by rain intrusion each year. At this pace, the Ogallala will be substantially exhausted by 2030. The implications of this impending crisis for the Great Plains, the United States, and the rest of the world are staggering and should be a key focus of our national political discussion. Sadly, they are not.
At some point in the next 10 years, as the exhaustion of the Ogallala becomes too obvious to continue to ignore, I suspect the first response from Washington, D.C. will be to try to wish the problem away. Be on the lookout for statements like this one: “we don’t have a water supply problem, we have a water distribution problem,” leading to the suggestion that we start diverting water from the Mississippi river for irrigation in the Great Plains. This type of thinking leads to over-exploitation of river systems. Consider that until new restrictions were enacted recently, the Colorado River, a river so strong that it carved the Grand Canyon out of the rock, dried up before it hit the Pacific due to the volume of water removed for irrigation. Draining the Mississippi to irrigate the Great Plains is not a rational or long-term solution to our issues of trying to bring population and resources into a sustainable balance.
With the caveat that the Missouri and Mississippi are effectively two branches of the same river, my prediction, highlighted above in bold, has come true in Kansas.
The economy of Kansas is highly dependent on perhaps the most water-inefficient agricultural system ever developed, growing corn to feed cows to produce beef. It requires a whopping 1,850 gallons of water to produce a pound of beef, compared to 400 gallons for a pound of eggs, 220 for a pound of pasta, 34 for a pound of broccoli, and only 26 gallons for a pound of tomatoes.
In order to grow corn and raise cows, Kansas farmers have been pumping water out of the Ogallala aquifer 24/7/365 for decades. As a result, the level of the Ogallala has dropped so low in 30 counties that water can no longer be extracted. Now that their wells have run dry, Kansas farmers are casting their gaze at the Missouri River, which forms part of the Kansas-Missouri border.
The proposed Missouri River Aqueduct would extend 360 miles – about ¾ the width of Kansas – to bring water to those dry counties. (See the map at the top of the page.) The United States Army Corp of Engineers estimates the cost of the project, including 15 pumping stations required to move water uphill, would be $18 billion dollars, and that it would take 20 years to complete. (My engineering instincts are telling me that both the cost and time estimates are probably low.)
Although I am not surprised that this project has been proposed, I am still disappointed. To me, it represents yet another attempt to delay dealing with the constraints Mother Nature has imposed. Consider the following:
- a significant portion of the world’s food production is dependent on pumping water from underground aquifers;
- effectively, this means that we are growing today’s food with rain that fell hundreds, or even (in the case of the Ogallala) thousands of years ago; and that
- many of the world’s largest aquifers are on pace to go dry in the next 10-30 years.
Therefore, we are not too many decades away from having to produce one year’s worth of food from one year’s amount of rain. (Note: if you are thinking, “what about desalination?” please go back and read my water series from 2012. The short answer is “too much energy consumption.”) While we could forestall this day of reckoning a bit with projects like the proposed Missouri River Aqueduct, we would then end up with the double whammy of having empty aquifers and dry river beds. This can’t be the best we can do.
What we need to do is to transform our food production systems to dramatically reduce the amount of water required to produce the calories and nutrients that we need. The good news is that we already know what to do. First, we need to consider our food choices. I like a good steak as much as the next guy, but when I realize that with the amount of water required to make a pound of my filet mignon, instead I could grow 71 pounds of tomatoes, I have to start questioning my choices.
We can also dramatically reduce water consumption in outdoor grain and vegetable production with improved soil management techniques, including no-till farming, use of cover crops, and providing the proper environment for bacteria and fungus in the soil. Water consumption in food production can be reduced further yet by growing food indoors with hydroponic systems.
So if we are going to invest $18 billion to assist farmers in Kansas, let’s not dig a big ditch and drain the Missouri-Mississippi River. Instead, let’s invest this money in research into low-water agriculture and subsidize farmers who are transitioning to these methods.
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