Will We Innovate a Solution to Water Scarcity?

Mix rising urban populations with climate-changed cycles of precipitation and drought. Add infrastructure stuck in the mid 20th century, overpumped aquifiers, and wetlands filled with development. What do you get? Unprecedented water scarcity.

"The era of cheap water is over," says Heather Cooley, director of research at the Pacific Institute, a think tank that emphasizes policy solutions for sustainable water management.

Beyond conservation, there is a proven technology being used worldwide to expand fresh water supplies: desalination. Governments turn to it because the plants pump out city-sized quantities of fresh water quickly and reliably, says Cooley—but it’s a solution that can create other problems. For one, desalination is energy-intensive, which drives up costs and creates carbon pollution. Further, "Seawater is habitat," Cooley says, "it’s not just salty water." According to a Pacific Institute study, one day of large-scale desalination operations can kill millions of minute marine organisms, as well as dump tens of thousands of gallons of concentrated brine back into the environment.

Given desalination’s downsides, the latest wave of water innovators are focusing on clean-energy-powered technologies or updates of age-old energy-free methods.

Source Hydropanels, from Arizona startup Zero Mass Water, combine solar energy with proprietary materials and a touch of cloud computing to harvest water from ambient air. Using sunlight to create heat, the panels condense and collect water from surrounding cooler air into a hydrophilic membrane. A network operations center can remotely monitor and tweak panel performance based on the data they share on weather conditions. Founder Cody Friesen touts Source’s utility for disaster relief but also for homeowners: A $4,500, two-panel array produces 4 to 10 liters of water daily, according to the firm.

WaterSeer, an invention by Vici Labs in Virginia, also uses small solar cells to power a condensation system, but exploits the difference between above-and below-ground temperatures to fill a cistern with an estimated 11 to 14 gallons of water a day. WaterSeer’s design is promising, but its inventors have drawn criticism for overestimating its potential effectiveness across conditions and environments.

The Italy-based Architecture and Vision studio collaborated with a rural Ethiopian village to develop the Warka Tower, a zero-energy, recyclable-mesh-covered bamboo structure that collects rain, fog, and dew and filters the water into a storage tank. Depending on the weather, the prototype can harvest 10 to 20 gallons of water daily, and its design can be adapted to make use of locally available materials.

A common feature of these new water-harvesting solutions is that they can scale from single homes to megacities, allowing residents, communities, and governments to decide when and where centralized versus decentralized solutions can create the most water security.

• In 2016, then–U.N. Secretary General Ban Ki-moon warned that by 2025 two thirds of the world’s population could be living under water-stressed conditions.

• To provide enough water for all uses by 2030, some analysts predict the world will need to invest $1 trillion in water conservation, infrastructure construction and replacement, and sewage works.