Over the next several centuries, filtration techniques changed very little until , when Sir Robert Bacon made considerable advancements with sand filtration to eliminate salt from sea water. By the 18th Century, the development of the microscope had given scientists new insight into the countless microorganisms present in water. In turn, many nations began using filters made of charcoal, sponge, and wool to eliminate unwanted organisms and particles.
Mid-way through the 19th Century, British scientist John Snow made a profound discovery when he determined that cholera was transmitted through water. After several experiments, he also found that chlorine could be used to purify contaminated water, resulting in the use of chlorination as a popular form of water purification.
By the 20th Century, most developed countries had established regulations that set minimum standards of water quality. This prompted the development of the advanced filtration methods we use today. Modern technology allows water treatment facilities to effectively eliminate the majority of harmful substances from public drinking water.
At the same time, many Americans also enjoy access to affordable private filtration systems, which make water even cleaner and better tasting. The result? Some of the cleanest, safest drinking water history has ever seen.
Pelican Water Blog. Water in the News. The general principle in the developed world now was that every person had the right to safe drinking water. Starting in , public health concerns shifted from waterborne illnesses caused by disease-causing micro organisms, to anthropogenic water pollution such as pesticide residues and industrial sludge and organic chemicals.
Regulation now focused on industrial waste and industrial water contamination, and water treatment plants were adapted. Techniques such as aeration , flocculation , and active carbon adsorption were applied.
In the s , membrane development for reverse osmosis was added to the list. Risk assessments were enabled after Water treatment experimentation today mainly focuses on disinfection by-products.
An example is trihalomethane THM formation from chlorine disinfection. These organics were linked to cancer. Lead also became a concern after it was discovered to corrode from water pipes. The high pH level of disinfected water enabled corrosion.
Today, other materials have replaced many lead water pipes. Toggle navigation. History of water treatment Created by S. Enzler MSc Significant historical events forming the basis for today's water treatment systems In ancient Greek and Sanskrit India writings dating back to BC , water treatment methods were recommended. People back than knew that heating water might purify it, and they were also educated in sand and gravel filtration, boiling, and straining.
The major motive for water purification was better tasting drinking water , because people could not yet distinguish between foul and clean water. Turbidity was the main driving force between the earliest water treatments.
Not much was known about micro organisms, or chemical contaminants. After BC , the Egyptians first discovered the principle of coagulation. They applied the chemical alum for suspended particle settlement. After BC , Hippocrates discovered the healing powers of water. The main purpose of the bag was to trap sediments that caused bad tastes or odours. In BC , Rome built its first aqueducts. Archimedes invented his water screw.
Aqueducts The Assyrians built the first structure that could carry water from one place to another in the 7th century BC. It was 10 meters high and meters long, and carried the water 80 kilometres across a valley to Nineveh. Later, the Romans started building many of these structures. They named them aqueducts. Roman aqueducts were very sophisticated pieces of engineering that were powered entirely by gravity, and carried water over extremely large distances.
Water in the aqueducts fed into lead, ceramic or stone pipes. During Roman times, aqueduct water supplied public baths, latrines, fountains, private households and farm lands. These engineering marvels took years to complete and covered a length of km. They were revolutionary for their time and are still the basis of our modern-day sewer systems. Greek engineer, Archimedes, lived between and BC. He invented a machine like a screw to move water from low to high ground.
The screw was initially used to irrigate farmland by pumping water from ship bilges and mines. It turned manually by windmill, manual labour or cattle labour. As the screw moved, the bottom scooped water from the low-lying source and pushed it up the tube until it poured out the top. This device is still in use today in several northern European towns. More importantly, it serves as the basis for many modern industrial pumps. After the fall of the Roman Empire around AD, aqueducts were either deliberately vandalised or fell into disuse through lack of maintenance.
During the middle ages AD little progress was made to provide clean drinking water to the population. Yet it was around this time that the premise of clean water not necessarily being safe water took hold. Sir Francis Bacon was the first known scientist to discover desalination. His experiments and studies brought him to the conclusion that if he percolated seawater through sand, then the salt would be removed.
His attempts to desalinate water were not successful, but they did pave the way for further research into this area. Antonie van Leeuwenhoek was a Dutch spectacle maker, obsessed with object magnification. He experimented with grinding lenses to make microscopes and view the microbial world. In , one of his at-home experiments involved used his microscopes to view tiny drops of water. Scientists now began to understand that removing harmful microorganisms created safe drinking water.
These filters used a combination of wool, sponge and charcoal to remove sediment and particles. In the late s, Robert Thom developed the first water treatment plant in Scotland. Thanks to this plant, the entire city of Paisley, Scotland, had access to safe drinking water via pipes for the first time. The decrease in waterborne diseases as a result of filtered water from this plant led to the Metropolis Water Act of This law required all water supplied to London be treated by slow sand filtration.
In , a cholera epidemic erupted in Soho, central London. Slow sand filtration was already in place, thanks to the new Metropolis Water Act. Thanks to the initial work of Antonie van Leeuwenhoek, he identified tiny cholera bacteria in the water through a microscope.
He successfully treated the cholera with chlorine. Snow determined that the cause of the outbreak was an individual water pump in Soho. A nearby sewer contaminated the pump, leading to cholera infection. Ironically, residents at the time noted the water from this pump had overall good taste and quality.
This again reinforced that taste and visual clarity do not indicate pure water for drinking. It forced the UK government to introduce chlorine, along with slow sand filtration, as the standard for water filtration. This soon spread to other developed countries in Europe and America.
In London at that time, drinking water from the Thames was contaminated with raw sewage, so epidemics of cholera and typhoid were common. This was one of the first carbon cartridge type filters. From this point on, Doulton filters were used by the military, Crown Agents and hospitals and were gradually introduced into the home.
Doulton was knighted by King Edward VII and given the honour of using the Royal Crest for his products in recognition of his work with drinking water filtration.
The range and efficiency of this water filter system has changed over the years but the popularity and effectiveness of the early 20th century invention continues with these water filter systems are still widely used across the world today. Chlorination, in conjunction with sand water filter systems, resulted in the virtual elimination of diseases such as cholera, typhoid and dysentery.
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