Rivers Have A Memory, Lessons From The Landslide Of Mocoa
A deadly flash flood and landslide in southern Colombia is a brutal reminder that people can't take the environment for granted.

-OpEd-
CALI — As humans we've been ignoring nature when we take decisions that affect our progress. We rush to conquer territories, increase the areas we cultivate for food, and extract minerals like coal from the earth's bowels to fuel our society. Every day we want more and more, and we perform immeasurable feats to satiate our greed. But when nature strikes back, we grow weak and look for culprits to blame for everything going on around us.
We already know how brutal nature can be: temperatures become extreme, cold snaps kill the vulnerable. Interminable droughts cut off our access to water but we've also witnessed the opposite: when water rushes in from under our doors or mixes with boulders and mud to come crashing down on us.
The question remains: Who is guilty when natural disasters strike? Who should we blame? After a landslide destroyed the Colombian town of Mocoa in the southern department of Putumayo, it may not be easy to answer those questions right now. More than 1.5 million people suffered from flooding this past winter in Colombia. And that doesn't include the victims of the April 1 flash flood and landslide in Mocoa, where the death toll has risen above 300.
Many attribute phenomena like torrential rain to global warming and, they are right considering the changes in the movement and release of vast amounts of water in different microclimates. But we must also consider people's carelessness when occupying mountainsides, stripping these areas of tree cover and leaving them vulnerable to soil erosion.
Rivers, too, have an almost instinctive tendency to seek out historical courses in spite of recent changes to the landscape or the presence of vegetation. Rivers, it is often said here, have a memory — and that can become a calamity waiting to happen. These ancient courses are often ignored when communities expand. Our grandparents spoke of the histories of water sources and how rivers would previously cover varied terrain. They warned us against settling near rivers without knowing their histories. It's unwise to build on sunken terrain like that which exists in several parts of Cali. For now, residents in this city are protected by a dike, which disturbingly, is increasingly covered by illegal settlements (the jarillón). In recent years, Cali has expanded northeast, onto terrain previously covered by tributaries of the Cauca river.
Civil engineering is certainly important and benefits lives but we also need knowledge of water, risk management and environment. This ensures we can keep living in our beloved Santiago de Cali, a district at high risk of flooding.
I don't see a single culprit when it comes to natural disasters, whether it is climate change, careless communities or mismanagement by the local government. It is our collective fault, for our lack of understanding and failure to make decisions that favor life over profits. We must adopt social and scientific perspectives that involve reconciliation with nature. We must understand the dynamics of our environment.
It is time to proceed with caution across a planet that's changing from the one we have known.