2 May 2012

Die water footprinting, die!

While in Oxford, I attended a session in which Dr Dave Tickner (WWF-UK) gave an "apologetic" presentation ("Beyond metrics: can water footprinting improve water security?") in favor of using water footprinting as a tool -- one of many -- for managing water.

Despite his humble tone, I saw two big problems with this "one tool in the box" idea:

First, footprinting is an imperfect measure of "appropriate" water use. It takes the same amount of water to raise a cow on rainfed pasture as it does to raise one on irrigated alfalfa. Water scarcity (demand vs supply) matters more than water use (demand per unit).*

Second, footprinting is the wrong instrument for setting policy: a "footprint" disclosure/requirement is not necessarily comparable with price information, due to the first problem (what does it mean?) and an additional problem (what's the value/importance of water within the overall production or purchase decision?)

These two problems make me dislike footprinting, but a third problem -- political naivete -- makes me much more nervous, to the point where I want to remove "footprinting" from any discussion of public policy. That's because I can see how a politician would love to impose some naive form of "footprint disclosure" or regulation on businesses or consumers.**

Such a policy would enrich footprinting consultants, but it also risks creating the perverse impacts that we have seen with biofuels policies (corn ethanol leading to groundwater depletion, higher food prices and ecosystem pollution; biodiesel leading to clear cutting rainforests for palm oil plantations).

So, I don't care if companies want to waste money on measuring their water footprint, but PLEASE PLEASE PLEASE keep footprinting out of laws and regulations. It's MUCH better to concentrate on pricing water for scarcity and/or regulating water use for sustainability.

Oh, and I'm not alone. I asked one senior water guru from a Fortune 500 company how much of $1 million from his company he'd invest in footprinting and how much he'd put into programs supporting "local sustainable water use." His answer? Zero percent into footprinting. This is a guy who knows and cares about sustainable water use from field experience. That matches my "academic" intuition.

Footprinting is a clever attempt to measure impact in the absence of prices, but scarcity-adjusted prices (via markets or regulations) are far more effective at conveying useful information that can be integrated into production and consumption decisions.

Bottom Line: Forget footprinting as a measure of impact. It's more important to balance supply and demand to prevent shortage than to care about the number of units of demand that a product represents.

* This over-simplification is no accident. The "creator" and main proponent of footprinting -- Arjen Hoekstra -- is an engineer, and engineers are notoriously good at building whatever you like without regard to the cost. Economists are more sensitive to the tradeoffs in any project.
** I discuss the abuse of regulations in the business of water in this recent paper.


  1. One minor correcting point, which also serves to emphasize the pointlessness of the whole "footprint" gabble-fest. Under all but the most optimal conditions, irrigation produces far more forage per acre than rainfall alone. Irrigated alfalfa produces far more digestible protein per acre foot of applied water than either irrigated or rain fed pasture does.
    So, do we concentrate on applied water, the economic value that water generates, the amount of land needed to produce X amount of meat or milk, the value that pasture would generate if it were turned into a Wal-Mart or holistic healing center, or....

  2. One of the largest flaws in water footprint thinking concerns its purely volumetric fetish. "Large footprints are a 'waste' while small footprints are 'efficient'" In the footprint context, producing the same output with less water is a successful case. (the cow on pasture/alfalfa example).

    Yet, under population and resource pressure, one can be certain that, inherently, water footprints will drop. With it, water-food systems will not only grow "more efficient" but will collapse. The water footprint of a thirsty cow will be minimal. So, expect that e.g. the collapse of a civilization like Angkor Wat was preceded by really efficient water footprints due to dire population/resource pressures.

    The difference between a small footprint due to "wiser" management or a small footprint under dire resource pressure is highly relevant but largely unaddressed in footprint-thinking. Yet this is where many people in the water sector (outside the footprint niche) have been focusing their work on for years.

    In defense, water footprint people tell that it is a new concept and still under development. Smart arguments, taken from conventional age-old water resource thinking, are in the mean time incorporated in order develop water footprints into something more useful. In five-to-ten years, there will be little difference between water footprint thinking and the rest of water resources thinking (of now). This seems to merely be a diverging learning curve to get footprint thinkers at the same level of cutting edge water/economic science; while vice versa there are a mere one or two useful simple perspectives offered in footprint thinking that make it useful to water resources thinking.

  3. Water footprinting is nice for educational purposes: gives people a good sense of how much water it costs to produce goods and food. But I totally agree with DZ: not suitable to drive water and food policy for the simple reason that impacts of water use (i.e. costs and benefits) are local, and not global as with CO2.

  4. As an engineer, I take issue with your aside. Engineers aren't, in fact, "notoriously good at building whatever you like without regard to the cost." We are good at building what we can at exactly the price you specify. At least of the hundreds of engineers I know and work with that is the case.

    We don't design things willy-nilly. We ask for specifications and ask for cost expectations and then begin. A more correct statement, and maybe your point worded differently, is that we'll design exactly what you want if you tell us price doesn't matter. This point was taught to us on day one, class one, hour one of the engineering program I attended. Cost is what matters, the rest is just math and imagination.

    The rest of your post is spot on. Price is one of human-kinds best inventions.

  5. Appalling, Really3 May 2012, 20:38:00

    I agree with magilson above, but would go further.

    It is, in fact, politicians and other magical-thinking academicians that routinely build, mandate, regulate, and otherwise interfere and inhibit without regard to the costs, financial or otherwise... and certainly "without regard" is the most favorable interpretation. I would suggest that "cynically in spite of" is more accurate.

  6. @marilson and appalling -- TOTALLY agree. My apologies. IMO, politicians are definitely driving the show, BUT there are SOME engineers who say "this is the solution and it costs $X" without considering other (non-engineering ) solutions that cost <$X. That may be the case with ones who've been out of school for too long to remember their humility...

  7. Yes, lay off the engineers. I just spent the day with a team that is looking at how best to manage pollution from old mines in the long term.

    They want to do some initial work to stabilise the situation, then monitor performance and try some (cheap) measures to reduce loads and promote natural attenuation. Really good cutting edge (and socially optimal) stuff.

    But they are getting lots of pressure from politicians and financial people, driven by local and global business interests, all of whom are more concerned to sell nice profitable BOOT plants. And the money interests are aided and abetted by environmental advocates who loudly demand "action now" (and to hell with the cost, government will pay).

    So also recognise the limits to prices and acknowledge that politics and money will always drive decisions, particularly in the field of water where social and economic are so deeply inter-twined.

  8. Water footprints are an interesting topic, new to and popular amongst policy-makers that think they now understand something of global water problems. It has a big 'so what' factor, though.

    Rather than killing the concept, why not educate those who feel they should incorporate it into policy-making? It seems that the shout box of water footprints is more prominent on the mind of politicians than that of 'pricing water' or 'regulating water use'.

    Maybe water economy should become more sexy by offering wet dreams rather than wet feet. Just a suggestion.

    Stay away from being a cure for insomnia. You are doing well, sofar.

  9. @Mr X -- it would be a disaster to incorporate it into policy, since its meaning is vague. Prices, like the price of oil or peanut butter, are not just better in giving good signals -- they are familiar and robust for policy.

  10. We should gather up a small group of economists and write a piece on the failure of footprinting to inform policy. Perhaps using a simplified scenario to inject concreteness.

    Or has this been done already? I'd like to know.

  11. I am not aware if it has been done. Sounds like a good project - I'd be up for contributing

  12. What about this reference? I found it rather complete...
    "Assessing Water Footprints Will Not be Helpful in Improving Water Management or Ensuring Food Security"

    There is also this one, but it seems to miss some obvious points...
    "What is wrong with virtual water trading?"


  13. Thanks for the cites Niksin.

    If anybody has other references questioning/bashing footprinting or virtual water, keep me posted please.



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