Featured Research

from universities, journals, and other organizations

'Man-made' Water Has Different Chemistry

Date:
June 20, 2008
Source:
Duke University
Summary:
As population growth, food production and the regional effects of climate change place greater stress on the Earth's natural water supply, "man-made" water -- created by removing salt from seawater and brackish groundwater through reverse osmosis desalination -- will become an increasingly important resource for millions of humans, especially those in arid regions such as the Middle East, the western United States, northern Africa and central Asia.

As population growth, food production and the regional effects of climate change place greater stress on the Earth’s natural water supply, “man-made” water – created by removing salt from seawater and brackish groundwater through reverse osmosis desalination – will become an increasingly important resource for millions of humans, especially those in arid regions such as the Middle East, the western United States, northern Africa and central Asia.

But the introduction of this life-giving water will bring changes to the environment.

“Water that’s been desalted through reverse osmosis contains a unique composition which will induce changes in the chemistry and ecology of aquifers and natural water systems it enters,” says Avner Vengosh, associate professor of earth and ocean sciences at Duke University’s Nicholas School of the Environment.

A new study by Vengosh and colleagues in France and Israel provides tools to identify and trace this man-made water as it mixes with natural water supplies and, over time, replaces natural waters in areas entirely dependent on desalination.

The study, published this month in the peer-reviewed journal Environmental Science and Technology, details for the first time the isotope geochemistry – or chemical fingerprints – of the elements boron, lithium, strontium, oxygen and hydrogen found in reverse osmosis-desalted seawater and brackish groundwater.

Identifying these unique geochemical and isotopic fingerprints gives scientists and water-quality managers a new array of tools for tracing the presence and distribution of man-made fresh water in a region’s soils, surface waters and ground waters, Vengosh says.

“We studied the chemistry of water produced in several of the largest desalination plants on earth and found that that composition of the desalted water is totally different from those of natural waters,” he explains. “As this water leaks into the environment through poor infrastructure or enters it directly through irrigation, it will be possible to use our new tracers to track the water back to its origin.

“It’s sort of like a detective who collects fingerprints at the scene of the crime and matches them to the guilty suspect,” he says.

Being able to trace water back to a desalinated source through its isotopic and geochemical fingerprints will allow local governments and water utilities to zero in on the problem of valuable water loss and correct it more quickly and efficiently.

Moreover, because desalted wastewater can be recycled through the environment and reused as a drinking water source – a process already being used in southern California – the new tools would enable water authorities to trace the relative contribution of desalted water in their system, and to test the effectiveness of their water treatment processes.

“This will be especially beneficial in water-scarce regions like California or the Middle East, where natural water sources are diminishing and made-made waters are becoming the ultimate water sources,” Vengosh says. “Given the complexity and variety of man-made fresh water sources being used to replace natural recharge in these regions, traditional tests alone, such as testing for water salinity, cannot provide a single solution.”

Global capacities for producing freshwater through desalination are projected to double by the year 2015, he notes. In some regions, diminished natural water supplies already are problematic. In California, which is experiencing one of its worst droughts in decades, new housing and other development is being slowed or stopped under a state law that requires a 20-year water supply as a condition for approval before building can begin. Increased use of freshwater produced through desalination could help resolve this issue, Vengosh says.

Vengosh is a geochemist who is internationally cited for his expertise on the chemical and isotopic composition of water contaminants. His research has led to the development of new, more accurate methods for tracing contaminants in water supplies worldwide, from boron-laden surface and ground waters in the Middle East to radon-contaminated groundwater in the mountains of western North Carolina.

He co-authored the new study with Wolfram Kloppmann, Catherine Guerrot and Romain Millot of the Bureau de Recherches Geologiques et Minieres of France, and Irena Pankratov of the National Water Commission of Israel.


Story Source:

The above story is based on materials provided by Duke University. Note: Materials may be edited for content and length.


Cite This Page:

Duke University. "'Man-made' Water Has Different Chemistry." ScienceDaily. ScienceDaily, 20 June 2008. <www.sciencedaily.com/releases/2008/06/080619135123.htm>.
Duke University. (2008, June 20). 'Man-made' Water Has Different Chemistry. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2008/06/080619135123.htm
Duke University. "'Man-made' Water Has Different Chemistry." ScienceDaily. www.sciencedaily.com/releases/2008/06/080619135123.htm (accessed July 31, 2014).

Share This




More Earth & Climate News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Big Waves In Arctic Ocean Threaten Polar Ice

Big Waves In Arctic Ocean Threaten Polar Ice

Newsy (July 30, 2014) Big waves in parts of the Arctic Ocean are unprecedented, mainly because they used to be covered in ice. Video provided by Newsy
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com
Amid Drought, UCLA Sees Only Water

Amid Drought, UCLA Sees Only Water

AP (July 30, 2014) A ruptured 93-year-old water main left the UCLA campus awash in 8 million gallons of water in the middle of California's worst drought in decades. (July 30) Video provided by AP
Powered by NewsLook.com
In Virginia, the Rise of a New Space Coast

In Virginia, the Rise of a New Space Coast

AP (July 30, 2014) Every summer, tourists make the pilgrimage to Chincoteague Island, Va. to see wild ponies cross the Assateague Channel. But, it's the rockets sending to supplies to the International Space Station that are making this a year-round destination. (July 30) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



    Save/Print:
    Share:

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile: iPhone Android Web
    Follow: Facebook Twitter Google+
    Subscribe: RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins