When you ask people why the area from the Pampanga River basin to Manila Bay is often flooded, most of them will cite poor solid waste management, resulting in heavily silted rivers and waterways, or climate change. Only a few, if any, will cite land subsidence as the main cause of flooding.
Although the first two factors do cause floods, land subsidence aggravates flooding more than the other contributors do.
In their 2006 article in Oilfield Review, Dirk Doornhof et al. wrote that when too much ground water is extracted from the reservoir, land compaction happens, leading to land subsidence, or the sinking of the land surface as a result of ground water extraction. Based on a 2015 study by Arnold van ‘t Veld, the yearly subsidence rate of up to 4.5 cm. in the Pampanga River and Manila Bay areas will continue. This means that a house that is two meters above sea level today will be flooded in 50 years.
Ground water extraction is an environment activity similar to mining but is neither regulated nor monitored by any government agency.
The major extractors of ground water are the local water districts, which are government-owned and operated corporations (GOCCs) that sell to their concessionaires water extracted through large pumps. The extraction leads to land compaction, and then to land subsidence.
Sadly, these local water districts are still in denial.
In mid-2015, a meeting was called by the Alyansa ng mga Baybay Bayan ng Bulacan at Pampanga, an inter-LGU alliance of coastal communities in the two provinces. This alliance, which includes the Jesse M. Robredo Institute of Governance of De La Salle University, aims to solve to common coastal community problems such as flooding. Representatives of local water districts were invited to one of their meetings to understand the sentiments of the alliance.
During the meeting, I saw how a representative of a local water district did not accept the idea that local water districts are one of the main causes of land subsidence despite the studies and researches mentioned by the facilitators. In contrast, large water utility companies such as Maynilad and Manila Water and the government-led MWSS have resorted to bulk water systems because they know that extracting ground water is not sustainable.
A bulk water system is composed of reservoirs and pipelines that supply potable water from a source (e.g., Angat Dam) to consumers. It avoids using big, deep well pumps. Local water districts hesitate to connect to this type of water system because doing so will increase their expenses, which they will have to pass on to their consumers.
I am sure these water districts know what is happening in Cape Town.
Just three years ago, Cape Town was awarded for its water conservation policy. Today, it is facing a severe water crisis. If the water districts in the Philippines continue to extract water, we, too, will be facing water scarcity soon. To be in a heavily flooded area without having a drop of water to drink is a scene not far from reality in the Pampanga River Basin and Manila Bay area.
Saving the environment and making operations sustainable come with costs.
Nonetheless, local water districts should start investing in water systems that do not extract ground water so that floods will not worsen. In the Netherlands and Japan, which are also below sea level, ground water extraction is prohibited.
Private-public partnerships can be explored between the LGUs and local water districts so that the water districts can connect to bulk water systems at reasonable costs. Educating the public, especially children, on water conservation is also important.
If we conserve water, we will not need to extract ground water. As suggested by Jocelyn Ho in her article in CSR Asia, businesses should monitor their water use and improve the conditions of their local water basins. Businesses and citizens should be informed about the greater cause of flooding (i.e., land subsidence) so that they can lobby for regulations and policies on ground water extraction.
As we celebrate World Water Day today, let us reflect on what the English historian Thomas Fuller wrote: “We will never know the worth of water till the well runs dry.”
Menchie Ann V. Canlas is a part-time instructor at Bulacan State University and an MBA student at the Ramon V. Del Rosario College of Business of De La Salle University. She wrote this essay for her class in Lasallian Business Leadership, Ethics, and Corporate Social Responsibility during her first term in the MBA program.