A look back through the history of water purification in appreciation of the purifying processes we use in the modern world.

Two thirds of the planet is covered by vast oceans of water. Nevertheless, without water purification, most of it isn’t even safe to drink. Water purification processes take dirty water and makes it clean again, but when did humans first start to use them? Let’s find out.

Dirty Water Makes Us Sick

The history of water purification has its origins in the premise that dirty, salty, or contaminated water can make us fatally ill. The need to remove those contaminants, potential parasites, and unsafe bacteria developed because our early ancestors witnessed the deaths and illnesses associated with unclean water and decided to do something about it.

A Little Bit of Water History

Although legend holds that humans built early water filters as far back as 4,000 years ago, nobody ever wrote anything down. Thanks to the lack of written skills, the first written version of a water filter comes from Hippocrates in 3BC. The Romans piped water throughout the land using aqueducts and are largely considered the inventors of plumbing. Hippocrates, however, used a sleeve of black cloth to filter his water to make it clear. He was doing this at a time when others were still capturing rain water in barrels – which would always become contaminated over time.

Moving slightly forward from the times when humans assumed water was drinkable if it was clear, we have the development of the well (pre-Roman but with visible evidence). Humans learned they were far less likely to become sick if they drank water from a well. This is because the water in wells was naturally filtered. They were also tapping into the water below the surface, which was far less likely to be dirty. It is even possible that they did this after observing animals do it.

water purification

The Three Modern Types of Water Purification Process

After this, we developed desalination, and then reverse osmosis, and finally solar stills – and not necessarily in that order. Here is an in-depth look into these three modern types of water purification process, so you can understand the trials faced by modern water companies.

Reverse Osmosis

Reverse osmosis is the complex modern version of Hippocrates’ sleeve. This method was developed in 1748 by Jean-Antoine Nollet, a French priest. Reverse osmosis means pushing large volumes of water through a semi-permeable membrane. This method takes lots of power but removes contaminants, chemicals, salt, and anything else that isn’t a water molecule. Of course no water purification process is completely failsafe, but reverse osmosis comes close.

Desalination

Desalination plants are how most of the UK get their water. This process is also popular in desert regions, where the only option is to remove potable drinking water from the sea. This process for purifying water involves removing salt, contamination, and particles from the water using chemicals. The desalination process evolved for farm use, too. Desalination plants might be vital, but they release brine which is often discarded into the oceans, causing environmental issues.

Solar Stills

The final method of producing clean drinking water is using solar stills. These large scale operations use sunlight and a clear membrane to make water. Seawater or any contaminated water is placed on the bottom level and allowed to evaporate. As it does, condensation drips down into your container as potable water.