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Monday, May 25

Not simply a consumption paradox: Pundita snaps at two nice water experts

From a May 19 editorial by two California-based water experts for The Conversation, Doug Parker and Faith Kearnsrepublished by Newsweek May 24, titled California’s Drought: There Will Never Be Enough Water:
[California's] abundant water supplies have helped create an incredible agricultural industry that leads the world in production. At the same time, given the size of the state, we will always have more land available to bring into production than we will have water to put on it.

This paradox -- that enough water will never be enough -- means that efforts to increase the supply of water or reduce demand for water will ultimately lead to more agricultural lands being brought into production, more water available for cities to grow, and more water to remain in streams to ensure a healthy environment. But, eventually, we will face a new drought, and water supplies will again be inadequate to meet the new, higher levels of demand.
There are other arenas where this phenomenon is well understood. For example, when it comes to freeways, congestion leads to demand for more lanes to be built. More lanes temporarily reduce congestion and lead to increased housing construction, and over time, that increased housing construction leads to more congestion. That, in turn, leads to demand for more lanes.

This is also true with flood control: Better levees lead to safer communities, which cause communities to expand and demand even better levees.
Accepting this fundamental paradox doesn’t mean that we should throw our hands in the air and do nothing -- and in fact, we aren’t. We should be, and are, looking at augmenting supplies and increasing conservation efforts.
I'm going to stop the authors right there. It's just the conservation efforts that have caused me sleepless nights since I read the stunning observations by another water expert, as reported in the May 25 edition of the New Yorker (Where the River Runs Dry): many conservation efforts actually exacerbate hydrological droughts -- and, if I understand correctly, can even create them. 

In other words conservation efforts such as the use of drip tape and other technologies and methods meant to stop water waste are hitting humanity in our most vulnerable place: groundwater supplies.
So this goes beyond a troubling paradox; this is a disaster.

The terror of the situation is that the disaster has been unfolding quietly, across decades, set in motion by the very best of intentions to conserve irrigation water.

What really blew my mind is that I've spent much of the past year plowing through thousands of water-related reports -- yet before the New Yorker report, not a single one I read brought out that there are very serious problems connected with water conservation!

In fact it's just the opposite; many of the reports are full of advice on how to conserve water and strenuously warn on the need for farmers to convert to drip tape and other water-conserving technologies.    

Yet the downsides of conservation are set to skyrocket now that government administrations in this country and around the world have come alive to the scope of water shortage crises.  These governments are throwing money at any company selling water conservation methods -- and within the past two years such companies have proliferated like rabbits!

This is in addition to millions -- maybe hundreds of millions -- of farmers in the USA and around the world, with no prodding or financial assistance from the government, installing drip tape to waste not a drop of water.

Yet it is just this 'waste' that flows into the ground.  And that way of recharging groundwater would be critically important in an arid and semi-arid region, or one that depends on very uncertain annual rainfall, wouldn't it?

This situation is worse than shooting yourself in the foot. This is bailing water while the person standing behind you keeps punching more holes in the boat.  That's a skewed metaphor under the circumstances but the only one that comes to mind at the moment.

And David Owen's report for the New Yorker only scratched the surface of the issue -- it wasn't even the central theme, which was about the Colorado River.  That means the problems with water conservation weren't headlined, and that anyone who read only the first part of the report didn't come across the bombshell.
So I wish Doug Parker and Faith Kearns would tell me how to proceed because I'm at my wit's end. I've turned myself and my blog inside out during this past year to inform readers on the scope of the water shortage crisis. But all the while I was parroting the advice of hundreds of water experts who didn't know, or forgot to mention, that there are serious knock-on effects with increasingly popular types of water conservation.

Here, again, is what David Owen wrote; there are aspects of the situation that reflect the consumption paradox but he and the water expert he quotes are talking about something that distinctly relates to water conservation:  
Reducing waste seems like an obvious solution to overuse, but it can actually make the problem worse. Bradley Udall, a scientist at Colorado State University’s Colorado Water Institute -- his family has been prominent in conservation and in regional and national politics for decades -- told me that water use can be divided broadly into two categories: consumptive and non-consumptive. 
When a farmer irrigates a field with river water, he said, some of the water is consumed by whatever the farmer is growing and by evaporation, but some is returned to the stream. The ditch system in the Grand Valley carries runoff and surplus irrigation water back to the river, and that water is used again, mainly by other farmers. (Kent Holsinger told me that, on average, river water is used more than half a dozen times before it leaves the state.) 
Excess irrigation water also soaks into the earth, replenishing groundwater and, eventually, feeding surface streams.
Udall said, “Efforts to improve water efficiency in agriculture almost always lead to increases in the consumed fraction. On an individual field, they make it look like we are using water better, but they actually move us in exactly the wrong direction.” 
Modern, efficient irrigation techniques can cause crop yields per acre-foot to rise, but also increase water consumption, so downstream users who relied on excess from upstream -- the non-consumed fraction -- now have to find water somewhere else. Increasing efficiency also does nothing to address over-allocation. Indeed, it can make over-allocation more dire, by allowing uses, and even the total number of users, to grow. 
Waste, paradoxically, is a kind of reservoir. If the residents of a suburb routinely water their lawns, they can stop during a drought. But once they’ve replaced their Bermuda grass with cacti and gravel, and once the water that formerly ran through their sprinklers has been redirected to bathrooms and kitchens in brand-new subdivisions, the enlarged system is more vulnerable in dry periods, because it contains less slack.
Cox drove me past a field in which one of his employees was planting lettuce, and parked by another ditch. “This is some of our citrus, here,” he said. “It’s grapefruit. It’s been flood-irrigated in the past, but we’re switching it all to micro-sprinkler.” 
Doing that will reduce Cox’s water need, but it will also have the perverse efficiency effect that Bradley Udall described, by turning a non-consumptive use (irrigation runoff) into a consumptive one (more grapefruit).
That’s an especially complicated issue in the Imperial Valley, because runoff from farms like Cox’s is the only source of water, other than modest amounts of rainfall and mountain runoff, for the Salton Sea, an immense but shrinking and increasingly threatened lake at the northern end of the valley. [He means water in addition to water received from the Colorado for irrigation.]
Conservation has had other negative effects in the region. Water from the Colorado is transported to the valley by the All-American Canal, which was completed in 1942. It used to leak tens of thousands of acre-feet a year into the desert along its route. In 2010, as part of the Quantification Settlement Agreement, a concrete-lined replacement for the most porous section was completed. 
But it turned out that the leakage had sustained a fragile Mexican wetland, which dried up when the leakage stopped; leakage had also provided irrigation water for Mexican farms near the border. 
Lining the canal didn’t reduce water use or turn waste into a new resource; instead, it transferred an existing resource from Mexico to Southern California, creating a shortage that then had to be relieved with water from somewhere else.

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