Our water pipes crawl with millions of bacteria

December 16, 2015
Our water pipes crawl with millions of bacteria
A glass of water contains millions of bacteria. Credit: Lund University

Researchers from Lund University in Sweden have discovered that our drinking water is to a large extent purified by millions of "good bacteria" found in water pipes and purification plants. So far, the knowledge about them has been practically non-existent, but this new research is about to change that.

A glass of actually contains ten million bacteria! But that is as it should be – clean tap always contains . These bacteria and other microbes grow in the plant and on the inside of our water pipes, which can be seen in the form of a thin, sticky coating – a so-called biofilm. All surfaces from the raw water intake to the tap are covered in this biofilm.

Findings by researchers in Applied Microbiology and Water Resources Engineering show that the diversity of species of bacteria in water pipes is huge, and that bacteria may play a larger role than previously thought. Among other things, the researchers suspect that a large part of water purification takes place in the pipes and not only in water purification plants.

"A previously completely unknown ecosystem has revealed itself to us. Formerly, you could hardly see any bacteria at all and now, thanks to techniques such as massive DNA sequencing and flow cytometry, we suddenly see eighty thousand bacteria per millilitre in drinking water," says researcher Catherine Paul enthusiastically.

The video will load shortly

"From having been in the dark with a flashlight, we are now in a brightly lit room, but it is only one room. How many different rooms are in the house is also an interesting question!" she continues.

The work of doctoral student Katharina Lührig, who works together with Catherine, professors Peter Rådström and Kenneth Persson, and colleagues Björn Canbäck and Tomas Johansson has been published in Microbes and Environments.

The results have led to lively discussions within the industry about the role of biofilms in .

At least a couple of thousand different species live in the water pipes. According to the researchers there is a connection between the composition of bacteria and water quality.

"We suspect there are 'good' bacteria that help purify the water and keep it safe – similar to what happens in our bodies. Our intestines are full of bacteria, and most the time when we are healthy, they help us digest our food and fight illness, says Catherine Paul.

Although the research was conducted in southern Sweden, bacteria and biofilms are found all over the world, in plumbing, taps and . This knowledge will be very useful for countries when updating and improving their water pipe systems.

"The hope is that we eventually may be able to control the composition and quality of water in the water supply to steer the growth of 'good' that can help purify the water even more efficiently than today", says Catherine Paul.

Explore further: Tap water warning in Copenhagen after E.coli found

More information: Katharina Lührig et al. Bacterial Community Analysis of Drinking Water Biofilms in Southern Sweden, Microbes and environments (2015). DOI: 10.1264/jsme2.ME14123

Related Stories

Leveraging bacteria in drinking water to benefit consumers

August 8, 2012

Contrary to popular belief, purified drinking water from home faucets contains millions to hundreds of millions of widely differing bacteria per gallon, and scientists have discovered a plausible way to manipulate those populations ...

Bacteria in drinking water are key to keeping it clean

August 14, 2013

Research at the University of Sheffield, 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 ...

Working with communities to keep drinking water safe

March 18, 2015

When we think about unsafe drinking water, our minds may leap to contaminated wells in developing nations or flood damage to sewage systems. It's easy to feel removed from these issues. Yet each year viruses, bacteria and ...

Professor offers primer on energy usage and drinking water

November 20, 2015

In January 2015, the U.S. Environmental Protection Agency (EPA) estimated that a staggering $2.6 billion worth of treated drinking water is lost each year due to leaking water mains and approximately 240,000 main breaks. ...

Recommended for you

Japan scientists detect rare, deep-Earth tremor

August 26, 2016

Scientists who study earthquakes in Japan said Thursday they have detected a rare deep-Earth tremor for the first time and traced its location to a distant and powerful storm.

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

betterexists
3 / 5 (2) Dec 16, 2015
If so, Are Water Treatment Plants a Sheer Waste?
Killing ALL Good Bacteria there with Bleach?
What is Going on?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.