If you’re lucky, you never have to think about your water. You just turn on the tap – or press a dispenser in your fridge – and fill up a glass. Fortunately (for the most part), our water is completely safe to drink. You might be surprised to learn, though, that water treatment methods actually date back thousands of years.

2000 to 300 BC

Going back to 2000 B.C., writings in both Sanskrit and ancient Greek reveal that treating water was recommended, not so much for cleanliness but to make it taste better. Methods included boiling, straining, and using sand and gravel filtration.

In around 1500 B.C., the Egyptians discovered coagulation. Using the chemical alum, they figured out how to suspend particle settlement. The walls of a tomb actually depicted this with pictures.

Around 500 B.C., Hippocrates – who understood the importance of water – invented a way of sieving water with a bag filter that became known as the Hippocratic sleeve. This device removed sediments that caused a bad taste or smell.

Between 300 and 200 B.C., Rome started building aqueducts. To shield them from pollution – as well as possible destruction from wars – most of them were built underground. Around this same time, Archimedes invented his water screw, which transported water to higher ground from lower bodies of water.

1600s to the 1800s

For nearly 2,000 years, there really weren’t any notable water treatment updates. (A good chunk of this time is the Middle – aka Dark – Ages, which was notorious for a lack of innovations, so it’s not too surprising.) That all changed with Sir Francis Bacon and his experiments with seawater desalination in 1627.

At this point, the developments started coming (relatively) fast. In the 1670s, Dutch spectacle makers inadvertently invented the microscope, and in 1676, this invention allowed Antonie van Leeuwenhoek to get a close look at water microorganisms.

The first water filters for home usage were created in the 1700s and consisted of wool, charcoal, and sponge. In 1804, Scotland built the first municipal water treatment plant, which was designed by Robert Thom.

In 1854, there was a cholera outbreak in London which spread through water. British scientist John Snow discovered that it was caused by sewage water contaminating water pumps. He then put chlorine in the water to purify it, which was the big impetus for water disinfection and chlorination. It wasn’t long after that governments started installing municipal water filters.

The U.S. began building large sand filters in the 1890s to protect the health of the American public. These utilized rapid sand filtration, which George Fuller realized worked better when coagulation and sedimentation techniques were also used.

1900s to the Present

While waterborne illnesses around the world abated thanks to chlorination, it was soon apparent that chlorine created another public health problem, namely respiratory disease.

In 1902, Belgium started putting calcium hypo chlorite and ferric chloride in its drinking water, which resulted in coagulation and disinfection. The next year, water softening was invented as a way to desalinate water. Ozone began being used as a disinfectant in France in 1906, and around this time, home water filters became prevalent.

In 1914, drinking water standards were put in place for public drinking water, and those were applied to municipal drinking water in the 1940s. In 1972, the U.S. passed the Clean Water Act, and the Safe Drinking Water Act went into effect in 1974. Then in the 1980s, the first membranes for reverse osmosis systems were developed.

Thoughts on Water Treatment History?

Did you know any of this water treatment history? Does anything surprise you? Let us know!