What Seven Technologies Both Old and New Are Helping to Fight Freshwater Scarcity Around the World?

January 27, 2020 – Welcome back to Emily Folk, who has previously provided four contributions to 21st Century Tech blog. Emily likes to write about sustainability and renewable energy. You can read more of her work at her blog site Conservation Folks. But in this contribution to 21st Century Tech blog, Emily focuses on the technologies that are being deployed to combat the world’s growing scarcity of freshwater resources. In human prehistory, and in more recent historic events, when freshwater sources dry up, civilizations vanish. So enjoy the read and as always, comments are encouraged.

Without food and water, humans die. Without access to clean water, they get sick or worse. That’s precisely why the United Nations considers water a fundamental right for all humanity. It’s also one of the United Nations Sustainable Development Goals.

Every person needs 20 to 50 liters daily of safe, clean freshwater to survive. That’s not just for drinking, but also for cooking and bathing. While the United Nations and affiliated organizations are trying to meet this threshold, 2.5 billion people today, according to the World Health Organization, lack access to reliable freshwater. And for many of the 2.5 billion the water they do access requires a 3o-minute or greater round trip daily.

There are many reasons why people experience water insecurity. Population growth is a major factor. Groundwater depletion is another. Competition for freshwater makes freshwater even more scarce as farming irrigation, manufacturers, and energy producers consume vast quantities.

Contaminated freshwater through poor sanitation often renders sources of supply useless. It isn’t always because of consumer behaviour, but rather often from negligent business practices leading to severe contamination.

Luckily, today we have a few a number of technologies that can help us fight the freshwater problem. I’ve picked seven to talk about.

1. Water Filtration

In some places, the problem isn’t access to water, but freshwater contamination. That’s where filtration can help. Filters automatically remove harmful contaminants from freshwater, making it safe to drink. Water filtration systems are not an expensive technology to develop. They are, however, energy intensive, which makes for problems in Developing World countries.

Combining filtration systems with local or distributed renewable energy solutions, however, can solve the power problem giving remote and off-grid areas safe water for drinking and other household uses. Whether solar, wind or geothermal, the energy gained to power filtration can also be used to turn on lights, and refrigerate foods for storage.

A filtration technology known as reverse osmosis can also be used to create fresh water. Reverse osmosis which uses specialized membranes doesn’t require a lot of energy to provide clean water making it an excellent choice for communities struggling with contaminated water sources.

2. Desalination

Nevermind rivers, waterways and other smaller water sources, if a city or country is located within a reasonable distance of the ocean, desalination becomes an option. The process of separating salt and water is a well-established technology that produces incredible quantities of clean water. Desalination plants are expensive to build and have a limited lifespan or require periodic refitting. Add to these issues the need for lots of power makes the desalination option a bit less attractive for those in the Developing World. And then there is the problem of what to do with the leftover salt from the desalination process.

3. Portable Filtration

Traditional water filtration methods can be condensed to generate small, portable filtration tools and devices. When distributed to a local populace, the devices instantly provide access to clean drinking water. Portable technologies like xylem filters, represent an inexpensive way to produce fresh water that has 99% of contaminants removed. The filters are produced from the inner lining of trees and a small length of a tube made from xylem removes 99% of contaminants, and up to 4 liters of water daily, enough drinking water to sustain a person daily. 

4. Air Wells

Natural condensation happens all around our planet when warm air cools resulting in it losing some of its moisture content. We see it each day with morning dew. Today, there are a number of technology options for collecting fresh water this way. Called air wells, on a small scale, they generate quantities of fresh water sufficient to keep a person hydrated every day. And because they condense out of the air, there are no contaminants. Devices like the DewBank and other water harvesters cannot solve the larger issue of freshwater scarcity, but can easily provide small scale solutions for individual use.

5. Fog Catchers

Fog catchers are a variation of air wells. They are used to collect passing moisture. Large deployed nets get deployed daily to collect freshwater from the air. In some areas prone to fog, hence the name fog catchers, substantial quantities of water can be harvested daily. In the past the nets were made from natural fibers. But today nanomaterials made from polymers are being used to harvest freshwater in both desert and mountainous environments.

6. Hydrolysis

In some places, toxic chemicals contaminate ground and surface fresh water sources. Using hydrolysis these contaminants can be neutralized. The U.S. Army has developed a portable chemical processing and disposal system that employs a reagent connected to a central reactor. Hazardous chemicals are siphoned into the reactor, then mixed with water and a reagent until the water is clean.

7. Stormwater and Runoff

Stormwater and runoff collectors provide two additional sources of fresh water. A msall treatment facility or portable device can both collect and clean runoff. The U.S. Navy has developed, tested, and patented a system that works like a multiple layered sand filter. When stormwater and runoff enter the system, the fluid passes through the layers to suspended particles and toxic elements like metals.

So these seven technologies that Emily has described can help us find freshwater relief for the moment. But will it be enough?

The United Nations in a recent report estimated that half of the world’s population will be living in freshwater stressed areas by 2030, and that 250 million of in Sub-Saharan Africa will be at greatest risk. A different study looked at 70 cities, in 39 countries, with urban populations greater than 750,000 today face extreme freshwater risk. And it is estimated that by the end of the century nearly three-quarters of us will be facing freshwater shortages. Deploying some of these described technologies may help. Improvements to water conservation practices are also desperately needed. And some are even calling for population control of our species as a way of ensuring there will be enough fresh water to go round in the centuries to come. 

Back in 2013, I posted a blog with a link to a video clip that juxtaposed four spheres. the first was Earth, the second was a sphere representing all the water of the planet, the third was all freshwater resources, and the last all accessible freshwater. It certainly puts the issue of freshwater scarcity into a new perspective. Freshwater is already scarce on this planet. We abuse it at our peril.