Earth’s drinking water crisis
Water is life”, an average human can survive up to 21 days without food but only 2-3 days without water. If you ask any medical professional, they will tell you that for a healthy lifestyle, a person needs to drink a minimum of 2-3 liters of water every day. But do we have enough water?
The answer to that question is a bit more complex. Almost 72% of our planet is covered in water, so according to that we have enough water, but less than 1% of that water is usable, and even that 1% is becoming less and less thanks to the rising water pollution, overexploitation of groundwater, and rapid urbanization.
As per UNICEF, currently, over 2 billion people live in the country with inadequate water supply, while 4 billion people experience severe water shortages for at least one month each year. While as per WHO by 2025, half of the world’s population will be living in water-stressed areas. The world is staring at a severe water crisis, especially in developing countries like India, sub-Saharan countries, etc. making innovative low-cost solutions the need of the hour. In this article we are going to list the various low-cost solutions being used or being developed around the world to combat the drinking water crisis:
Life Straw is a straw-shaped device invented by the Swiss company Vestergaard Frandsen. The device is a 22cm straw with a 3cm diameter containing a miniature filtration system and works exactly like a straw. The device is extremely useful for personal use in areas where poor-quality of water is available as it can filter harmful pollutants like protozoa, bacteria, VOCs, etc. A single straw is capable of filtering up to 4000 liters of water.
2. Solar Condenser
Solar condensers are another device that is used to treat contaminated water. The device uses sunlight to evaporate the water into vapors; these vapors are then again cooled into droplets in the condenser chamber using condensing material called polydimethylsiloxane.
3. Drinkable book
The drinkable book also known as the Safe water book is a device made by Folia Water. It is one of the simplest devices on the list. The book contains pages made up of filter paper coated with silver nanoparticles and is capable of eliminating bacteria, viruses, and other pathogens. The book was designed with the goal of providing poor people with cheap and easy access to clean water. Folia Water has already tested its product in many countries in Asia, Africa, and Latin America, and will soon start supplying them worldwide as part of humanitarian programs.
4. Graphite Oxide Sieve (Graphene filters)
Earth is covered in water, but the biggest problem is that almost all of that water is saline. The process of removing the salt from the water and converting it into potable water is known as desalination and is often considered to have high energy demand as well as being too expensive to be used. Graphene filters provide an alternative to the current desalination process, developed by scientists from the University of Manchester (United Kingdom), the process uses nano filters made from Graphite Oxide which allows water to pass through it but retains salt. It is a relatively new material and is still some years away from becoming a true solution
5. Atmospheric Water Generator (AWG)
As per the US geological survey, the volume of water in the atmosphere at any one time is about 3,100 cubic miles (mi3) or 12,900 cubic kilometers (km3), which is almost 6 times the total water flowing in rivers. AWG’s are the devices designed specifically to tap this huge source, these devices work on the principle of capturing water directly from the atmosphere. A few examples of such devices are:
a. MOF-based AWG: this device has been designed by a team of researchers from MIT and is based on 2 stage mechanism. The device which works on solar energy can extract drinkable water directly from the air even in dry regions, using specialized materials called metal-organic frameworks, or MOFs. The device can be scaled up to produce 20,000 liters per day and could act as a lifesaver in the desert region but currently, it is on the expensive side.
b. Wet desiccators: Desiccators use desiccant liquid (brine water) to absorb moisture from the atmosphere, from which water is then extracted. These devices can work in almost every climate (except highly arid regions) and are used extensively by the US army. The refined versions of these systems are capable of producing up to 700,000 L of water a day at cost of 2cents/liter. The only drawback these devices have is that they require a large area.
c. Fog Catchers: fog catchers are devices that capture moisture from fog and produce water. These are some of the simplest devices on the list and use vast mesh nets to capture fog. These devices are cheaper and easy to operate and can harvest up to 10000 L of water per day. These devices have the limitation that they can only be used in places that have very high humidity in the air like mountainous regions.
6. Rainwater Harvesting
While rooftop rainwater harvesting has been one of the best-known and most widely used methods to capture and store rainwater, recently many new innovative methods have been developed to capture rainwater and use it to recharge aquifers. These new methods include
a. catchment collectors: these are structures built to collect surface runoff from a catchment area. These structures usually contain an impervious catchment area from which the water is collected and send into an aquifer via a percolating pit, containing filter media (usually sand and gravel)
b. Percolating tiles: these are interlocking tiles that allow water to seepage through them and are used for paving footpaths or walkways
c. Permeable roads: these are road surfaces that are made such that they allow a large amount of water to pass through them to the bottom layers.
With each passing day more and more people are being exposed to the water crisis, to prevent that we all need to come together and work on finding solutions. The above list contains a few of the many solutions that are being implemented or developed worldwide to provide safe drinking water to the people, but the thing to remember here is that no one solution can single-handedly solve the global water crisis, we need to find multiple solutions and implement them in synergy with each other, only then can we get out of this crisis.