Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Larger cities have smaller water footprint than less populated counterparts

08.10.2018

Global sustainability is important now more than ever due to increasing urban populations and the resulting stress it can have on natural resources. But increased populations in cities may lead to greater efficiency, as a team of Penn State researchers discovered when they analyzed the water footprint of 65 mid- to large-sized U.S. cities.

"Human life on the planet has never been more complex," said Caitlin Grady, assistant professor of civil engineering. "We're so intertwined with so many aspects of the global trade and global economy. People in rural areas are still buying food like bananas from across the world and because of this we need more complex and rigorous tools to analyze how to manage our limited resources."


Water footprint of consumption and production for the analyzed US cities. The water footprint of consumption is separated into direct and indirect contributions.

Credit: Penn State

In order to develop these tools, researchers first need to better understand the urban water footprint. Grady and her colleagues set out to do just that.

"We looked at the overall picture of water consumption," Grady said. "Not just the water that comes out of your tap but also the water that goes into the food that each city produces and consumes, so it's both the direct water use and indirect water use, which we call your water footprint."

They analyzed agricultural, livestock and industrial commodity flows, and the corresponding virtual water contents using data from the U.S. Department of Agriculture, the U.S. Geological Survey and the U.S. Department of Transportation. The team then used these values to calculate an overall water footprint for each city. Their results were published in August in PLOS ONE.

What they found was that on average, larger cities, for their populations, consume less water.

"As the population increases, cities are consuming less per capita of the water resources, so the larger cities are getting more out of the water that they have based on population," Grady said.

Tasnuva Mahjabin, a doctoral student in civil engineering and contributing researcher on the project, said that multiple factors are likely contributing to these results.

"Water footprint consumption and production are tied to the changing composition of urban economic activities with city size, suggesting that large cities are more service-oriented with less prevalence to secondary sector industries," Mahjabin said. "This allows large cities to have reduced water footprints by shifting water-intensive economic activities to less populated regions."

And although the overall water usage decreased in correlation with a city's size, the researchers noted that not all types of water usage yielded a more efficient footprint.

Water that has been sourced from surface or groundwater resources mainly mirrored water-related weather patterns and showed little correlation with population. However, the amount of water used from precipitation contributed to consumption both positively - by transferring the dependence of food consumption on population into the water footprint - and negatively - by increasing diversity.

Several exceptions did arise. New Orleans, for example, has a much larger water footprint for their size and their population compared to the trend, whereas Las Vegas falls well below the average for water footprint production. The team is tracking the complexity of these findings in an effort to more accurately dissect the results.

The researchers hope to use their findings to benchmark cities and potentially set realistic targets to support the development of strategies for reducing the water footprint. This information could also be valuable to policy makers and city planners concerned with designing economic incentives that support water sustainability.

"A city in California may have a very strong campaign to have people take shorter showers and reduce water consumption, but they may also be a huge food producer," said Grady. "That's not necessarily a bad thing, but if you look at these things together you have a more complete picture of how you can manage the limited resources you have, and how you can prioritize the use of those resources."

In the future, the researchers plan to make their analyses more robust by incorporating more locations and including the water consumption needed to provide electricity to different regions. They would also like to analyze network resilience and network risk. Ultimately, they hope to create a platform where not only the public could investigate linkages but the government, as well.

###

Penn State aims to become a leader in sustainable water-energy-food nexus research. This research was partially supported by the National Science Foundation. Additional researchers included Alfonso Mejia, associate professor of civil engineering, and Susana Garcia, civil engineering doctoral student.

Media Contact

Jennifer Matthews
jas6149@engr.psu.edu
814-867-6224

 @penn_state

http://live.psu.edu 

Jennifer Matthews | EurekAlert!
Further information:
http://dx.doi.org/10.1371/journal.pone.0202301

More articles from Power and Electrical Engineering:

nachricht HZB researchers are used to boost the efficiency of silicon solar cells
04.10.2018 | Helmholtz-Zentrum Berlin für Materialien und Energie GmbH

nachricht Supersizing solar cells: researchers print module six times bigger than previous largest
02.10.2018 | Swansea University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Flying High with VCSEL Heating

Additive manufacturing processes are booming, with the rapid growth of the formnext trade fair a clear indication of this. At formnext 2018, the Fraunhofer Institute for Laser Technology ILT will be showing a new process in which the component in the powder bed is heated with laser diodes. As a result, distortion can be reduced, taller parts generated and new materials used.

In just three years, formnext has established itself as the industry meeting place to get the latest on additive manufacturing (AM) processes. With 470...

Im Focus: Breakthrough in quantum physics: Reaction of quantum fluid to photoexcitation of dissolved particles

Researchers from Graz University of Technology have described for the first time the dynamics which takes place within a trillionth of a second after photoexcitation of a single atom inside a superfluid helium nanodroplet.

In his research, Markus Koch, Associate Professor at the Institute of Experimental Physics of Graz University of Technology (TU Graz), concentrates on...

Im Focus: Chemists of TU Dresden develop highly porous material, more precious than diamonds

World Record of Cavities

Porosity is the key to high-performance materials for energy storage systems, environmental technologies or catalysts: The more porous a solid state material...

Im Focus: New function of “kidney-gene”: WT1 plays a role in the central nervous system and controls movement

The WT1 gene fulfills a central role in the development of a healthy, proper functioning kidney. Mutations in WT1 lead to impairments in kidney development and cause Wilms tumors, a pediatric kidney cancer. Researchers of the Leibniz Institute on Aging – Fritz Lipmann Institute (FLI) in Jena have now discovered a further important function of WT1. It is also active outside the kidneys in the central nervous system and is involved in controlling movement. If the gene is missing in the spinal cord, locomotor aberrancies occur. The results have now been published in Life Science Alliance.

Transcription factor WT1 (Wilms tumor 1) has been known for nearly 30 years and it is significantly involved in the development of a healthy and properly...

Im Focus: Master of the tree – novel form of dendritic inhibition discovered

A unique feature that sets neurons apart from all other cells are their beautiful, highly elaborate dendritic trees. These structures have evolved to receive the vast majority of information entering a neuron, which is integrated and processed by virtue of the dendrites’ geometry and active properties. Higher brain functions such as memory and attention all critically rely on dendritic computations, which are in turn controlled by inhibitory synaptic input. A team of scientists, led by Johannes J. Letzkus (MPI for Brain Research), now has identified a novel form of inhibition that dominantly controls dendritic function and strongly depends on previous experiences.

Our brain is a remarkably complex system. It is not only comprised of billions of neurons, but each individual neuron by itself even has exceptional processing...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

5th International Conference on Cellular Materials (CellMAT), Scientific Programme online

02.10.2018 | Event News

Major Project: The New Silk Road

01.10.2018 | Event News

"Boston calling": TU Berlin and the Weizenbaum Institute organize a conference in USA

21.09.2018 | Event News

 
Latest News

Journey to the Beginning of Time

08.10.2018 | Physics and Astronomy

Typical mutations in children of radar soldiers

05.10.2018 | Health and Medicine

Highly Organised Process: How Protein Complexes Form in the Cell

05.10.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>