Bacteria in drinking water are key to keeping it clean

The University of Sheffield News: Bacteria commonly found in drinking water creates conditions which enable other- potentially harmful – bacteria to thrive, says research by engineers from the University of Sheffield.

The research, published in the latest issue of Water Science and Technology: Water Supply, points the way to more sophisticated and targeted methods of ensuring our drinking water remains safe to drink, while still reducing the need for chemical treatments and identifying potential hazards more quickly.

The research team, from the University of Sheffield’s Faculty of Engineering, studied four bacteria found in the city’s drinking water to see which combinations were more likely to produce a ‘biofilm’. Biofilms are layers of bacteria which form on the inner surfaces of water pipes.

“Biofilms can form on all water pipes and as these are usually non-harmful bacteria, they don’t present a problem,” explains lead researcher, Professor Catherine Biggs. “However, biofilms can also be a safe place for harmful bacteria such as Escherichia coli or Legionella to hide. If the bacterial growth is too heavy, it can break off into the water flow, which at best can make water discoloured or taste unpleasant and at worst can release more dangerous bacteria. Our research looks at what conditions enable biofilms to grow, so we can find ways to control the bacteria in our water supply more effectively.”

Funded by the Engineering and Physical Sciences Research Council, the research isolated four bacteria from water taken from a domestic tap: two were widely found in drinking water everywhere, one was less common and one was unique to Sheffield. The researchers mixed the bacteria in different combinations and found that, in isolation, none of them produced a biofilm. However, when any of the bacteria were combined with one of the common forms, called Methylobacterium, they formed a biofilm within 72 hours.

...“This means it should be possible to control or even prevent the creation of biofilms in the water supply by targeting these particular bacteria, potentially reducing the need for high dosage chemical treatments...

From the tap, shot by Alex Anlicker, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license