Capturing the Rain in Mexico

Startup Isla Urbana says its technology can address chronic water shortages in cities

Seven hundred years ago, the land where Mexico City now sits was a vast lake that stretched across hundreds of square miles. Over the centuries, as early settlers built homes on dry land and later rulers drained the area to fight seasonal floods, the lake almost disappeared. Today, given the volumes being pumped from the aquifer beneath the ancient lakebed, the metro area of 22 million risks running out of water. The capital is sinking by as much as 20 inches per year, and homes endure frequent shutoffs and periods when what liquid comes out is clouded and smelly.

For Enrique Lomnitz, that smelled like opportunity. The Mexico City native and Rhode Island School of Design (RISD) graduate thought he could help households capture the abundant rain that mostly drains out to distant regions rather than replenishing the city’s supplies. “We have more rainfall than London,” Lomnitz says. “But that doesn’t filter down and recharge our aquifer.”

In 2009, Lomnitz founded what’s now called Isla Urbana (which means Urban Island) to promote a technology he’d devised with fellow RISD designer Renata Fenton. The idea was simple: If you keep the grime from the roof and the dust in the air out of your tanks and let the dirt settle, you can collect rainwater clear enough for mopping or doing laundry. Add more filters and a bit of chlorine, and you can drink it. The goal is “living with the water we have,” Lomnitz says, before “we import water or dig deeper for more.”