By Brian Moseti Snr. in August, 2016 for Science Made in Africa
After visiting rural Ethiopia, and witnessing first-hand the challenges that women and children go through looking for water, Italian architect Arturo Vittori was driven to help.
His solution, a clever machine, made of bamboo and banana fiber twine, which harvests between 50 and 100litres of water per day from the atmosphere.
The Warka Water is a vertical structure designed to convert fog and dew into potable water.
The system does not require electrical or mechanical power to run and is driven by the natural forces of gravity, condensation and evaporation.
The Warka’s water harvesting technique and construction was informed by ancient technologies, performing similar purposes.
Archeologists recently found structures from South England, which were designed to collect water by condensation, some of which are still working.
In the Mediterranean area too, Vittori and his team found stone piles positioned on top of holes, which were later found to be water collection systems. Vittori explained:
“The air, with humidity, passing in the spaces between the stones, condensed on the cooler stones within the pile, leading to water drops falling into the collection pit below.”
Further studies revealed that there are structures on animals and plants, which only recently have been discovered to be created to tap water from the atmosphere. Said Vittori,
“Plants and animals have developed unique micro- and nano-scale structural features on their surfaces, which enable them to collect water from the air and survive in hostile environments.”
By studying the Namib beetle’s shell, the lotus flower leaves, spider web threads and the integrated fog collection systems in cacti, the engineers identified various materials and coatings that can enhance dew condensation and water flow.
Termite hives informed the geometry of Warka’s outer shell, but the joinery and assembly was inspired by traditional construction in Ethiopia, “which is simple and only uses available material.” Vittori Added:
“We incorporated traditional Ethiopian basket-weaving techniques in the design.”
The woven pattern of the tower’s bamboo structure mimics the style of other structures in the region, incorporating a familiar aesthetic.
The system has four main components; the mesh, which traps water from the fog, the collector that also acts as a condenser and the collection tank.