Freshwater Management's Achilles' Heel

Our expectations of what the future will be like, of literally everything related to water, is based upon what we know to be true today and our knowledge of how things have evolved or changed in the past. Unfortunately, we now live in a time where we cannot predict the future with any reasonable level of confidence.


Achilles' Heel

Source - wikipedia.org

In Greek mythology, Achilles gained an impervious armor all over his body - except on his left heel - when his mother dipped him into the river Styx.
Achilles left heel did not get the body armor because his mother held his body from this heel while she dipped him into the river Styx. 
With his body armor, Achilles became virtually invincible and a fearsome warrior.
Achilles' successes continued until an opponent's arrow struck him in his unprotected heel - Achilles' left heel was his only weak spot.




The Assumption of Stationarity - Freshwater Management's Achilles' Heel

Source - Wikipedia.org

The concept of Stationarity implies that a system always fluctuates within a reasonably narrow envelope which can be created using historical facts - facts that are usually numerical measure-ments.
Non-stationarity implies the opposite i.e. extreme difficulty in the creation of an envelope because of extreme variability that shows no clear pattern or a pattern that never repeats because it continues to change.


Why Non-Stationarity Now?
Human actions have always impacted Stationarity. For freshwater management in the late twentieth-century, it was easy to add-in the existence and impact of variability induced by human action.
Today, however, the patterns of change have become so complex that there exists no model on variability - especially one that reconciles and is supported by instrumented measurements.
The uncertainties around predictions today are extremely large primarily due to global warming and the resulting climate changes. We cannot model the effects of global warming and the resulting increases in rainfall (precipitation) with a level of confidence that makes the model believable for the present and usable for predicting the future.


Freshwater Planning WITHOUT benefit of Stationarity
The Achilles' heel of freshwater predictions today is the inability of water managers to predict with any real confidence how water-resources will behave differently from their historical behaviour i.e.

• The risk of water shortages has increased - Rainfall will come, but where, when and in what amounts cannot be predicted
• Risks of floods has also increased - The location and intensity of flooding cannot be foretold

 The bottom line: Extreme uncertainty in predicting freshwater supply


What's Our Best Course of Action Now?
In this Anthropocenic Era, humanity must do what it has always done i.e. imagine an acceptable future and work hard to make it a reality. Mankind must primarily focus on developing approaches that supply freshwater on demand.