Colombia water works: Turning trash into cisterns

Ana Morales near Bogota, Colombia opens the tap on her Ekomuro — a rainwater cistern made out of discarded 3-liter bottles.
Ana Morales near Bogota, Colombia opens the tap on her Ekomuro — a rainwater cistern made out of discarded 3-liter bottles. Miami Herald

For more than a decade, Cecilia Uribe has relied on a higher power to provide a basic utility: water. In her sprawling neighborhood on the outskirts of Colombia’s capital, municipal water only ran twice a month, she explained, “so I would just wait for my God to make it rain.”

Capturing and storing that scarce resource, however, required more earthly intervention. For the past six years, Ricardo Alba has focused his attention on that simple but vital question: how to harness the rain in a country where more than three million people don’t have access to running water.

His solution — both simple and cheap — has been catching global attention. Alba, 56, developed a system for interconnecting discarded three-liter plastic bottles. The standard array, or Ekomuro H2O+, as he calls it, consists of blocks of nine bottles stacked six high. Attached to a gutter or downspout, the homemade cistern can hold 43 gallons of rainwater that’s available through a spigot at the bottom of the tower.

It costs less than $50 to build — even if people pay a premium for the bottles, he said. And it’s infinitely expandable. He’s created an Ekomuro for a school out of 324 bottles.

The heart of the system is an ingenious way of connecting the recipients. Alba uses a household iron to affix bottle tops back-to-back. After he bores a hole through them, he can screw a bottle on either end, creating six-liter reservoir. Each of those mini-cisterns is attached to a pair above it through food-grade silicone tubing.

“The great thing about using PET bottles is they’re standard almost anywhere in the world,” Alba said. “And we’re turning trash into something useful.”

The ubiquity of plastic bottles has given the Colombian system an international cache. Ekomuros are currently being built in Guatemala and Mexico, and Alba has received queries from Nepal, where the earthquake-damaged infrastructure has made water storage a necessity. When Alba’s display model was recently confiscated at an airport on his way to a conference in Asia, he simply made a new one once he landed.

His use of household garbage is winning accolades. Ekomuro was awarded a top prize at last month’s World Water Forum in Korea, was a finalist in the 2013 Technology and Innovation Competition of the Americas, and was a regional finalist in the 2012 Google Science Fair.

But the system got its start in the dusty hillside community on the periphery of the capital called Altos de Cazucá, which is dominated by tin and wood shacks.

Uribe, who lives in a small house with 10 family members, said she used to rush home every time it rained to catch water in old bathtubs, jars and buckets. One room of her tiny home was mostly dedicated to storing the water, she said.

Now that water is being held in the nondescript Ekomuro that stands outside her front door. (The bottles are always encased in wood or tin housing to avoid sun damage.) As she poured clear water from the cistern’s tap, she said she uses it for washing clothes, cleaning her house and, sometimes, cooking. And there’s usually enough left over for the neighbors, she said.

Social innovation has become a buzzword in Latin America for good reason. While the region has seen a growing middle class in the last decade, it’s still divided by deep income inequality.

“Development assistance to Latin America from wealthy countries is at a historical low, while government support for domestic social programs is in jeopardy in many countries because of falling economic growth rates and political constraints,” The Atlantic Council’s Adrienne Arsht Latin America Center wrote in a recent report called Harnessing Social Impact Investing in Latin America. “But where governments hit roadblocks, the private sector can step in to make important quality-of-life changes for millions of people, with innovations ranging from pay-as-you-go solar power to fresh farming practices.”

Alba isn’t behaving like an entrepreneur quite yet. He makes his money by giving lectures to local schools about recycling and his cisterns.

He runs the enterprise with his two children and he often donates his labor to help people build their own Ekomuros. (There’s a waiting list of about 100 people in the Altos de Cazucá alone.)

Lately, others have been trying to replicate his project as a business, he said.

“There are people who see the profit-making potential of this,” he said. “I say that’s fine as long as they’re using recycled material.”

He does, however, have ambitions for his bottles. He plans to use some of his recent prize money and donations to build an Ekomuro factory in Altos de Cazucá, where local residents might help mass-produce the system.

And he’s been tinkering with a passive solar water heater that could be connected to the cisterns. But even that relative luxury will adhere to Ekomuro’s no-waste philosophy: it will be made out of discarded beer cans.