Oct 24 , 2022
For most developed nations, clean water is often readily available for bathing or drinking for the majority of the population. You can buy it in stores or buy in-home water filtration systems fairly easily. Finding water for sanitation purposes isn’t difficult, either. Rarely do people doubt that the water is potable and free of major contaminants.
Sadly, this privilege does not extend to everyone. Roughly two billion of the world’s population does not have access to safe drinking water in their homes, and more than half of the world’s population does not have access to water used for sanitation. Many rely on wells, lakes or other sources of water that are easily contaminated. This leads to a host of health issues ranging from the superficial (rashes or skin irritation) to the life-threatening (cholera or parasites).
The United Nations designated access to clean water a human right in 2010, and, luckily, there are multiple methods to sanitize water without easy access to modern sanitation systems. In conjunction with Imagine a Day Without Water on October 20th, we’re bringing you a view of what it takes to bring clean water to places that need it most.
Home water sanitation systems are divided into two major types. The first is called point-of-entry, where water is filtered when it comes into the home via plumbing. This includes King Water Filtration systems. However, point-of-entry systems are only practical in homes that already have indoor plumbing, which isn’t always the case.
That’s where point-of-use systems can fill the gap. These filtration systems filter water where it’s directly accessed, like at a spigot or faucet. While point-of-entry systems can be more thorough, they can be more difficult to install. Point-of-use systems are often easier to distribute.
As you might remember from our previous blogs, contaminants come in many forms, ranging from biological to chemical. However, since health is the primary concern of these filtration systems, they focus on filtering out the viruses and bacteria that cause waterborne diseases. There are five common methods for household water treatment. As we’ll see, each has their own benefits and drawbacks.
Chlorination: Easy and Cost-Effective
This system relies on a diluted chlorine bleach solution to cleanse the water and make it safe for consumption. Once the solution is added to the water, you must wait 30 minutes before ingesting. This method is very effective at eliminating dangerous waterborne diseases like cholera, typhoid and more. However, its effectiveness can be lessened by turbidity, and the chlorine can negatively impact the taste as well. But since the solution is easy to make, it can be very cost-effective and easy to implement for an in-home filtration system.
Filtration Through Flocculation
In water treatment, flocculation is a process by which smaller particles introduced to the water expand over time, clumping together into larger particles that can be strained out to allow the flocculent to kill any viruses and bacteria lurking within. It’s also able to remove chemical contaminants like heavy metals. Currently, Procter & Gamble’s flocculent powder is the most widely distributed version, and it’s able to clean roughly 2.5 gallons of water per one 4-gram packet of powder. While the packets are relatively easy to distribute and cost-effective, the fact that the process requires straining and a relatively lengthy wait to clean a smaller amount of water than other methods is a drawback.
Here Comes the Sun: Solar Disinfection
One of the easier methods to use, solar disinfection uses the sun’s UV rays to disinfect water in plastic bottles. The disinfection process can take between 6 and 48 hours depending on the water source, which is a major disadvantage, and the process can take longer if cloudy weather occurs. Still, it is effective at reducing bacteria and is a simple system that doesn’t require much extra work to maintain, which makes it a good solution for developing countries.
Power to the Pottery: Ceramic Disinfection
This filtration method is fairly self-explanatory: By allowing the water to filter through a ceramic cistern into a plastic bin below, the filter reduces the amount of bacteria and Protozoa and creates a reserve that’s around 2.6 gallons of clean water for household access. In that way, it’s a ‘set-and-forget’ system. However, this method, like the others, can be very time-consuming, with clear water filtering less than a gallon per hour and even longer for high-turbidity water. It also doesn’t completely eliminate contaminants from the water and can lead to re-contamination without a chemical agent to treat the water stored for any length of time.
(Not So) Slow Sand Filtration
Don’t let the name fool you – slow sand filtration (SSF) is one of the quicker methods of water filtration! Using layers of fine sand, coarse sand and gravel in conjunction with a bioactive layer of water on top, the SSF can filter roughly 36 gallons of water in an hour. When used effectively, it can reduce bacteria and Protozoa by up to 99%. However, the system itself is very large. Likewise, the cost of transporting it and the time costs of setting it up can make it less accessible than is ideal.