Environmental Restoration Using Gabions
Commercial gabion construction (credit: Gabion Supply)
Leonardo da Vinci is famous for his curiosity and studying diverse and unrelated subjects: his enigmatic portraits; how the wings of birds perform; human anatomy; drawings of fanciful and elaborate contraptions of flying machines to military armaments; mountaintop geology, and the movement of water. Leonardo's notebooks, of which perhaps only 25% are known to have survived, continue being studied by contemporary investigators of many disciplines to garner new insights. An argument could be made that da Vinci was the godfather of biomimicry, geomorphology, and ecological restoration even though none of these R&D fields of research existed in the 15th Century. His illustrations, constructions, designs, and observations flow into each of these contemporary scientific, engineering, and construction enterprises.
A good environmental design example is Leonardo's utilization of the gabion, or what is called a corbeille, 'a basket of stones' in Italian. As the translation indicates, a gabion is designed and constructed using a sturdy wire mesh molded into a sturdy form that stabilizes another structure when filled with rocks. Gabions can be used in a building's foundation, to control a steep embankment, or as a way to reduce erosion of stream and river banks to capture and contain flowing water. The gabion directs, deflects, and reduces the force of the water helping to reduce its erosional impact. This traditional construction method of using simple materials to control flooding is finding many, new contemporary applications.
In most arid and semi-arid regions, deforestation and over-grazing has created vast denuded landscapes and reduced water supplies. The ability of gabions to deflect the force of floods, allows for containment ponds and sections in once dry creeks beds to retain water. It ponds up behind them and the water can then recharge aquifers and restore new vegetation. Several innovative organizations, Native American tribes, and commercial ranching operations in the Southwestern US and elsewhere have shown dramatic recovery of grasses and groundwater supplies where gabions have been installed. These designed and managed water projects, utilizing a classical civil engineering technology, kick-starts an ecosystem's recovery.
If Leonardo were alive today, the Renaissance master would likely be proud seeing the results of combining his design tools with an understanding of the recovery power of nature. WHB