A Bamboo Tower That Produces Water From Air

The WarkaWater tower is an unlikely structure to find jutting from the Ethiopian landscape. At 30 feet tall and 13 feet wide, it’s not half as big as its namesake tree (which can loom 75 feet tall), but it’s striking nonetheless. The spindly tower, of latticed bamboo lined with orange polyester mesh, isn’t art—though it does kind of look like it. Rather, the structure is designed to wring water out of the air, providing a sustainable source of H 2O for developing countries.

Created by Arturo Vittori and his team at Architecture and Vision, the towers harvest water from rain, fog and dew. This isn’t a new idea—people have been doing this for as long as they’ve needed water, often with air wells. Often built as high-rising stone structures, air wells gather moisture from the air and funnel it into a basin for collection. The WarkaWater functions in much the same way, using mesh netting to capture moisture and direct it into hygienic holding tank accessed via a spout.

How the system works. Illustration: WarkaWater

We wrote about the towers last year when Vittori unveiled a full-size prototype. The company has a newer version of the WarkaWater and a Kickstarter campaign to fund field testing in Ethiopia later this year. Based on tests performed in its Italian lab, the company claims the latest iteration can harvest 13 to 26.4 gallons of water daily. That’s less than most people flush away each day, but a significant quantity in a country where some 60 million people lack sufficient potable water.

The WarkaWater tower produces water by harvesting rain, fog and dew from the air. WarkaWater

Caption: A Warka tree. WarkaWater

The tower uses three system to capture each of the weather phenomena. A polyester mesh net fathers moisture from fog, rain collects directly into a holding tank and dew is directly down a funnel into the tank. WarkaWater

Caption: A Warka tree. WarkaWater

A prototype of the fog-harvesting netting. WarkaWater

The new prototype has some key upgrades:

• The exterior is of bamboo rather than juncus, 
• the top of the tower has reflective pieces to deter birds, and 
• the structure is larger (13 feet wide, up from 7). This doubled the surface area of its water-resistant polyester mesh netting—the orange material you see—so more water is collected as fog permeates the fine mesh. 

MIT has been researching a similar fog harvesting technique that draws inspiration from the Namib beetle. The process of collecting rain is straightforward, but capturing dew is slightly more complicated. Dew forms when the surface area temperature drops relative to the surrounding air. This happens most often in the time between nightfall and sunrise. Vittori is researching materials for the funnel section of the WarkaWater (between mesh netting and the tank) that will lose heat as quickly as possible in order to optimize the small window of dew-production.
The WarkaWater will cost around $1,000 to produce and requires no electricity. Vittori says it takes less than an hour to assemble the five modules into a finished tower, making it easily packed and moved as necessary. The practical goal is for the WarkaWater to become an efficient round-the-clock water production machine. But populating the landscape with alien towers is about more than just functionality, it’s about architecture. You can tell Vittori wanted to design something iconic, but beyond that is the tower’s potential to the social nexus of a village. With fabric canopies that stretch out like a peplum skirt, the towers could be a place where people gather to socialize and seek shelter from the sun, just as they would beneath a leafy Warka tree.

ORIGINAL: Wired