Groundwater may deplete by 2050 - UP study

MANILA, Philippines - Groundwater in the Philippines may be depleted by the year 2050, a University of the Philippines professor said in a report based on a study that started in 2006.

After simulating effects of high temperature and low precipitation in a shallow aquifer in Bay, Laguna, engineer Victor Ella said in his report that groundwater levels are incrementally declining starting at an average of 0.10785 meter per decade as yearly precipitation decreases.

"This could mean that by the end of 2050, groundwater levels are likely to decrease by 0.43138 meter, 0.45143 meter and 0.45177 meter if rainfall decreases by 0, 10 and 20 percent, respectively," Ella said, citing his pioneering experiment on the century-old aquifer.

The Bay aquifer supplied water for irrigation and domestic uses with 15 meter-thick layers of clay, fine sand and coarse sand.

Ella explained that he tracked changes in the climate using air temperature scenarios by the Intergovernmental Panel on Climate Change.

He attributed to the trend in the current decade with an annual precipitation lower than that of the three previous decades that affect pumping rate and the design and implementation of shallow tube wells that supply water to farms.

Increasing domestic, agricultural and industrial use of groundwater as well as economic development in the area, moreover, contribute to its impending depletion, Ella said.

"Lower groundwater levels are further aggravated by other factors such as land use change, improper well siting, well interference and excessive unregulated pumping, all of which increase the operation and maintenance costs shouldered by the farmers or private operators," he said.

The study, funded by the government through the Southeast Asian Regional Center for Graduate Study and Research in Agriculture (SEACA), is the "most advanced computer-aided analysis" of the flow, discharge, recharge and precipitation impact in groundwater sources, said SEACA director Gil Saguiguit Jr.

"The Ella study on groundwater was a significant contribution to the ongoing campaign by government to conserve water or use it responsibly," he said.

Ella used U.S. Geological Survey Three Dimensional Modular Finite-Difference Groundwater Flow Model for the study. - Camille Diola