Water resilience
Today’s water situation in Metro Manila reminds me of a similar situation we had 30 years ago. Back then, the metro also faced a critical shortage of power, facing up to 8 to 10 hours of power outages or “brownouts” daily. The situations are not exactly identical, but there are enough similarities from which to draw some lessons.
From 1989 to the early 1990s, Metro Manila suffered from rotating 8-10 hour power outages in the summer. This meant that some portions of the city faced a brownout sometime during the day. The main culprit then was the lack of supply of electricity for distribution to customers. The problem was not limited to Metro Manila; similar problems were experienced across Mindanao, again on account of lack of supply.
Working our way out of that power problem required close public-private sector coordination, a change in consumer behavior, demand-side management, better designs for energy efficiency, and longterm policy and legislation to address the problem of supply. A similar approach will be needed to address this water situation.
Angat Dam has, for many years, been the major source of water for the city; it supplies 97 percent of Metro Manila’s supply. The volume of water drawn down by the two water utilities—Manila Water and Maynilad—has been fixed since 1997. Three factors alone should have driven policy decisions to establish other sources of water for the city.
The first is population. In 1997, Metro Manila’s population was approximately 9 million people. By 2015, the population was 12.8 million (nighttime) and an estimated 16 million by day. By 2020, the population is expected to grow to 19.4 million. Today, the Mega Manila population (which includes areas just north, south and east of the metropolitan area) is 21.3 million. With no adjustments made in the volume of raw water drawn from Angat or from new sources, the only way to increase actual potable water supply is for the water companies to raise their efficiencies by cutting nonrevenue water (which includes all water not fit to serve, as well as leaks). Both companies have done that, and Manila Water has cut nonrevenue water to 12 percent, well within global standards. There is little more supply for it to add, without a new source of water.
The second factor is El Niño. Rainfall patterns have long been established and tracked, so periods of high and low rainfall have been known for years. Those patterns will likely shift over time due to climate change. The shift will be toward the extremes—either abnormally high rainfall that will lead to flooding in some places, or abnormally low rainfall and droughts that will contribute to water shortages (and curb agricultural production).
The third factor is the West Valley Fault. The Philippine Institute of Volcanology and Seismology estimates that the fault runs just 200 meters east of the Main Dyke. For this reason, the government, as far back as 2012, has embarked on a series of projects to strengthen the Angat Dam and Dyke. Can you imagine the impact of a 7.2-magnitude earthquake ( the Big One) on a dam that supplies 97 percent of Metro Manila’s water?
Warnings have been issued on the catastrophic effects of overdependence on a single source of water supply, considering these and other factors. But, as is usually the case with warnings, people pay no heed or little attention to them so long as supply is still there (as was the case with the power situation in the 1990s). Communication and coordination are absolutely important here.
Ultimately, policy and legislation need to be put in place to address the core issue of lack of supply. There are at least 11 bills pending in Congress for a Department of Water Resources or Water Regulatory Commission. Let’s hope they simplify the current structure of water management in the country, where as many as 30 agencies play a role. Hopefully, we can then move toward greater water resilience.
———— Guillermo M. Luz (luz.gm@ayala.com.ph) is chief resilience officer of the Philippine Disaster Resilience Foundation (www. pdrf.org).