When we drink a glass of tap water or wash in the shower today, the water we use is the result of thousands of years of refining techniques to treat this vital liquid and remove impurities. Water has always been crucial to human societies and attempts to treat it and provide a healthy and usable resource go back to ancient Greek and Roman times. Here's a brief history of how water treatment has developed over the years.
Water treatment techniques can be traced back to between 2000-4000BC. Prior to this, societies largely determined the quality of water supplies by taste, smell and appearance alone. More sophisticated techniques began to emerge in early Greek, Sanskrit and Egyptian societies with methods to improve water quality including boiling it in the sun and using rudimentary sand, charcoal or gravel filtration systems. The Egyptians developed a method of using alum to remove particles from water. Another early development was by the ancient Greek physician Hippocrates who invented the Hippocrates' Sleeve, a cloth filtration system. Whereas prior methods have been concerned primarily with water taste, the main purpose of the Hippocrates' Sleeve was to produce clean water for medical use.
Following this, the key developments over the next few centuries were around improving techniques for sourcing freshwater from further afield. The Romans created some of the earliest city-wide aqueducts beginning in the 4th century BC, building around 400km of infrastructure that supplied up to 250 million gallons a day. This was the beginning of centralized urban water supplies. Many of these aqueducts still stand today in countries such as Spain and Turkey. Around the same era the Greek engineer Archimedes invented a water screw, a precursor to the modern groundwater pump.
While early water treatment dealt with visible particles (e.g. cloudy water) and improvements to taste, it was the invention of the microscope in the 17th century that led to the next big leap forward in water treatment. For the first time, scientists could inspect water for micro-organisms and it was discovered that some filtration techniques couldn't eliminate microbial bacteria from supplies.
This included harmful bacteria linked to deadly diseases such as cholera and typhoid. In 1854, it was discovered that a cholera epidemic in the UK was spreading due to sewage-contaminated water pumps. This along with other disease outbreaks led to the discovery of chlorine as an effective disinfectant that could purify water supplies and remove harmful pathogens.
Chlorination, improved water filtration and better sewage treatment systems became more widespread in industrialised countries and cities from the late 19th century onwards, and in the early 20th century many of these countries implemented minimum national standards for the treatment of water.
Although there have been great water treatment improvements since the late 19th century, they
haven't been without accompanying problems. Since the 1950s, there has been a shift in emphasis from disease-causing bacteria to man-made pollutants such as pesticides, chemicals and industrial sludge that have been infiltrating water supplies.
Additionally, problems with creaky and leaky centralized piping networks, increasing urbanization leading to more stormwater waste, climate change affecting the water cycle, excessive industrial and agricultural water waste, and a global north-south divide where over 10% of the world's population still don't have access to clean water have meant that we are having to rethink our attitudes to how we supply and treat water.
New treatment techniques thanks to modern technology mean that not only can we further improve the quality of freshly sourced water but we can also treat alternative sources of water such as wastewater, seawater and rainwater to create a water supply for drinking, household and commercial use. These techniques include reverse osmosis, carbon filtration and electrodeionization. They offer the potential for sustainable and decentralized water supplies to be provided to households, businesses and communities, which could prove vital in tackling the looming water crisis which faces us all.
Water Experts can help you become more water-efficient. Whether you're a household, business enterprise or community, we can offer tailored advice and expertise as well as providing the most up-to-date products including our Q-Drop sustainable drinking water systems.
For a comprehensive overview on the history and future of water treatment, see David Sedlak “Water 4.0: the Past, Present and Future of the World's Most Vital Resource”