Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mixed water portfolio helps thirsty cities

19.01.2010
Computer simulations for drought-prone areas reveal that when urban water planners combine three approaches of buying water -- permanent rights, options and leases -- the city avoids surplus water and high costs, and reduces shortages, according to civil engineers.

"Just like with stock portfolios, if you buy diverse stocks, you diversify your risk," said Patrick Reed, associate professor of civil engineering, Penn State. "Right now, cities don't necessarily diversify their risk through the ways in which they buy water."

Reed and his colleagues are trying to understand the benefits and trade-offs associated with buying water using a mix of market instruments in the Lower Rio Grande Valley of southern Texas. Those models incorporated the various purchasing options, along with variables such as cost, amount of surplus water and the probability of water shortages.

The researchers found that when cities in the region rely solely on permanent rights, they could incur high costs -- $13 million a year -- and require lots of surplus water yet still face significant supply failures in drought years. Alternatively, a careful mix of permanent rights, options and leases can dramatically lower costs -- $10 million a year -- increase water available to the environment and avoid supply failures during droughts.

A major focus of the research is to provide decision-makers with water planning models that graphically illustrate how options, leases and permanent rights affect cost, surplus water and probability of water shortages.

"This work not only demonstrates how we can combine multiple objectives to solve a problem, but also visualize the problem and learn from it," said Reed. "It is an innovative hybrid between engineering and policy to create highly adaptive and resilient water supply systems."

Most cities that buy water rely on permanent rights to ensure reliable water supply. It is like buying a percent of the water flowing into a reservoir.

"But you do not know what the inflows are going to be so you are essentially buying a percent of a question mark," Reed adds.

Often the city ends up buying a lot of water to cover potential shortages, resulting in extra cost and surplus water that is not available for other uses. If a city fears there will be shortages, it can purchase a monthly lease to cover the shortfall. But because demand is already high by then, the city pays a high price for the water.

The other choice for urban planners is to use options, which let them buy water at lower prices at a later date.

"It takes the volatility out of pricing and they (planners) can buy a volume of water at the original price later in summer when demand is high," said Reed.

The researchers reported their findings in a recent issue of Water Resources Research. Reed says the team's findings are especially relevant in the face of growing population and climate change.

The team tested its model against the worst drought on record in the Lower Rio Grande Valley. It found that the city made significant savings and averted water shortages when it used a diverse set of market instruments to buy water.

"We were able to find a solution that does not have any critical water shortages, without having surplus water or substantive costs," Reed explained.

Researchers say the simulations present utility companies with a variety of solutions for efficient water management, along with the implications of each solution.

The simulations also suggest that utilities that start off with a less diverse portfolio begin to use more of the market when drought happens and the city starts running out of water. In contrast, when utilities use more of the market at the start, the city saves money and averts water shortages in a drought.

"Economic instruments such as leases and options provide a lot of flexibility to urban water planners, particularly in the western United States," said Reed. "They provide the ability to be resilient to droughts."

Other researchers on the project include Joseph Robert Kasprzyk, graduate student in civil engineering, Penn State, and Gregory W. Characklis, associate professor of civil engineering and Brian R. Kirsch, graduate research assistant, both at University of North Carolina at Chapel Hill. The National Science Foundation supported this work.

Amitabh Avasthi | EurekAlert!
Further information:
http://www.psu.edu

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>