MEANWHILE, the water needs of Metro Manila and other major cities have been increasing sharply. The unabated migration to the cities has brought the country's urban population to nearly 30 million, almost half the entire population, and stressing out the cities'water supply. As early as 1991, a study by the Japan International Cooperation Agency listed nine of the country's major cities as water-critical areas: Metro Manila, Metro Cebu, Davao, Baguio, Angeles, Bacolod, Iloilo, Cagayan de Oro and Zamboanga.

The water situation in rural areas is also nearing alarming levels, says Mario Vergel de Dios of the Water and Sanitation Project of the Department of Interior and Local Governments. Extreme climate changes such as those brought on by El Niño affect the rural water supply. Already, the government is predicting that more than 16,000 hectares of mostly corn land will be affected in Mindanao alone after El Niño arrives later this year. Also threatening water supply in rural areas are the degradation of watersheds and the drying up of wells.

The water problem is actually a shortage of freshwater that comes from rivers, lakes and the ground. Unlike water in the seas and oceans, the supply of freshwater is limited. Low rainfall especially in times of drought, and the over-extraction of water from the ground is further putting these water resources in critical condition.

Metro Cebu, which covers three cities and seven towns, for example, is 99 percent dependent on groundwater. Apart from the water drawn by the Metro Cebu Water District, there are thousands of individual deep wells that extract water from the ground.

Despite this, more than half of Metro Cebu's demand for water remains unmet.

The over-extraction of Cebu's groundwater has led to its contamination. In areas near the coast, saltwater has seeped into the groundwater. In other areas, leaks from septic tanks, dumpsites and industrial wastes are believed to have contaminated the water supply.

Such problems could have been avoided had there been strict regulation of groundwater extraction. In a rather belated attempt to reverse the situation, the NWRB's Dayrit has issued 1,884 cease-and-desist orders to establishments all over the country with known unregistered deep wells. The figure excludes Makati, Manila and several other key cities.

In the tourism haven of Boracay, the NWRB has identified 500 deep wells installed by business establishments sucking up the island's groundwater, not one of which is registered with the NWRB. The agency has threatened to close down all water pumps unless the owners register these and pay for the water they consume. According to Dayrit, Boracay's water table is already nearing critical levels and in danger of running dry soon.

There are similar concerns in Muntinlupa City, where there is a heavy concentration of industries and subdivisions. A study finalized early this year by the Philippine Institute of Volcanology and Seismology (Phivolcs) found "vertical movements with displacement ranging from 12 cm to 116 cm, and an average displacement value of 50 cm." The phenomenon is known as land subsidence, which means that Muntinlupa is sinking.

Groundwater extraction is believed to be the culprit. Operating wells were found to be 150 meters deep on the average. The Phivolcs team studying the sinking of Muntinlupa said "several wells extracting more than 1,000 cu.m/day are located within zones" where the largest land displacements and fissures were found. The team found three wells of a multinational beverage firm within that zone.

The report also cites a 1998 study presented by E.G. Ramos to the 11th Annual Geological Society of the Philippines that identifies "groundwater extraction as the probable cause of the subsidence not only in Muntinlupa City but also in almost all throughout Metro Manila."