Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sri Lanka water supply still suffers effects of 2004 tsunami

09.05.2006


Sri Lanka’s coastal drinking water supply continues to suffer the effects of the December 2004 tsunami, which caused major death and destruction in the region. Much of the island nation’s coastal area relies on wells, usually hand dug and relatively shallow. Some 40,000 such wells, each typically serving several families, were destroyed or contaminated by the tsunami. The continued sustainability of the aquifers that supply such wells is in doubt, due to continued saltwater contamination, erosion of beaches, and other human impacts, such as sand mining, increased pumping, and pollution, according to an international team of scientists and engineers.



The 14-member team from the United States, Sri Lanka, and Denmark, reports its findings in a paper scheduled for publication on 9 May in the American Geophysical Union journal Water Resources Research. During investigations in Sri Lanka from February through September 2005, they found that the tsunami had affected coastal drinking water sources in several ways.

First, the tsunami itself, which reached up to 1.5 kilometers [0.9 miles] inland, poured seawater, along with other contaminants, directly into the open dug wells, rendering those that were not destroyed unusable. In some areas, as many as four large tsunami waves struck, with the second in the series often the largest. Aside from contamination of wells, large quantities of seawater penetrated from the flooded surface of the land through porous layers below and into the aquifer.


Further, efforts to restore wells by pumping out seawater were sometimes apparently counterproductive, as excessive pumping may have allowed more seawater to enter the aquifer from below. This pumping also caused many wells to collapse, as their walls were not reinforced. Finally, contaminated water that was pumped out of wells was often discharged in places that permitted contaminants to seep back into the aquifer and again into the wells.

The researchers, led by Prof. Tissa Illangasekare of the Center for Experimental Study of Subsurface Environmental Processes, located at the Colorado School of Mines, found that one anticipated consequence of the disaster did not materialize. They write that fears of outbreaks of waterborne disease were not realized, due to public awareness of the need to disinfect wells and to practice good personal and food hygiene.

Although some of the affected coastal aquifers in Sri Lanka are composed of ancient limestone deposits, especially in the north of the country, most coastal groundwater is stored in sandy aquifers that are replenished by rainwater, especially during the October-to- February monsoons. This recharge has been slow in many of the most-affected areas, as they did not receive substantial rainfall for almost a year. The December 2005 monsoon rains were substantial, but the researchers say it will take several more monsoon seasons-- they do not know how many--for the aquifers to recover. In collaboration with the American, Danish, and Sri Lankan scientists, a group of researchers at the International Water Management Institute based in Sri Lanka is currently conducting long-term monitoring studies at selected sites.

The researchers say that since March 2005, salinity levels have declined slowly, if at all, in many of the wells that continued to be pumped. They note that planning is underway to provide piped water to many coastal villages, to supplant the individual, and vulnerable, open dug wells. Other social responses include plans for expansion of centralized sewage collection, proposed setbacks for housing along coastlines, and the use of new modeling techniques for integrated management of surface water and groundwater for sustainable water resources.

Around the world, devastating floods can be caused by more than tsunamis, the researchers note, including storm surges, hurricanes or cyclones, and rising sea level. They urge hydrologists to participate in the planning of emergency planning procedures that could greatly reduce human suffering. Documenting the hydrologic impacts of such disasters is, they say, the first step toward developing internationally recognized emergency guidelines for treating sources of contaminated water supplies and for long-term and planning tools for managing coastal groundwater in areas affected by seawater inundation.

The opportunity the group of scientists received to visit the site to observe damage and after-effects of the tsunami and to interact with local scientists will help to develop long-term research collaborations and educational programs to address critical water supply issues in the region, they say. The team has developed a number of recommendations, which they will present to the Sri Lankan government, to help develop local expertise and capacity- building in areas of modeling, data management, and subsurface characterization for integrated water management in the affected regions. The authors say they are continuing to work together to address Sri Lanka’s water needs.

Harvey Leifert | AGU
Further information:
http://www.agu.org

More articles from Earth Sciences:

nachricht Monitoring lava lake levels in Congo volcano
16.05.2018 | Seismological Society of America

nachricht Ice stream draining Greenland Ice Sheet sensitive to changes over past 45,000 years
14.05.2018 | Oregon State University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

Im Focus: Computer-Designed Customized Regenerative Heart Valves

Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.

Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...

Im Focus: Light-induced superconductivity under high pressure

A team of scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg investigated optically-induced superconductivity in the alkali-doped fulleride K3C60under high external pressures. This study allowed, on one hand, to uniquely assess the nature of the transient state as a superconducting phase. In addition, it unveiled the possibility to induce superconductivity in K3C60 at temperatures far above the -170 degrees Celsius hypothesized previously, and rather all the way to room temperature. The paper by Cantaluppi et al has been published in Nature Physics.

Unlike ordinary metals, superconductors have the unique capability of transporting electrical currents without any loss. Nowadays, their technological...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Supersonic waves may help electronics beat the heat

18.05.2018 | Power and Electrical Engineering

Keeping a Close Eye on Ice Loss

18.05.2018 | Information Technology

CrowdWater: An App for Flood Research

18.05.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>