ILOILO AQUIFERS UNDER PRESSURE: Water districts fall behind as demand exceeds supply — PIDS

By Francis Allan L. Angelo

Water districts in Iloilo and across Panay Island and Negros Occidental are among those grappling with supply deficits that mirror a nationwide pattern, as a new study reveals that water service delivery systems across the Philippines are falling short despite available water resources.

The Philippine Institute for Development Studies (PIDS), in its Discussion Paper Series No. 2025-50 titled “Securing Tomorrow’s Water: Insights on Groundwater, Surface Water, and the Role of Water Districts in the Philippines,” found that across 532 water districts, annual demand consistently exceeds effective supply — contributing to persistent service gaps even as 87.7 percent of the population is reported to have access to safe water.

The study specifically identified Panay Island and Negros Occidental as areas with a higher concentration of operating water districts, yet the Visayas as a whole recorded a coverage rate of only 68 percent from 2019 to 2024 — well below the 85 percent benchmark for adequate water district performance.

Groundwater extraction activities were also found to be highly concentrated along coastal areas in Iloilo City and Bacolod City, raising concerns about aquifer sustainability in the region.

Fewer than half of Filipino households have piped water connections at home, while 332 municipalities remain classified as “water-less,” with more than half of residents lacking reliable supply. An estimated 12.4 million Filipinos still do not have access to safe water.

Authored by PIDS Supervising Research Specialist Adrian D. Agbon, the study points to structural challenges in water service provision, particularly persistent supply deficits among water districts, that threaten long-term water security even in areas where water resources are available.

DELIVERY LIMITS, NOT SCARCITY

The Philippines appears water-rich on paper. The National Water Resources Board (NWRB) estimates the country has about 226 billion cubic meters of water available each year, including around 20 billion cubic meters of groundwater and about 206 billion cubic meters of surface water such as rivers and lakes.

However, most of this water — about 83 to 85 percent — is used for agriculture, leaving a smaller share for households, businesses, and industries.

The study notes that current supply gaps are driven less by raw water availability than by system capacity constraints among water districts.

As the population increased from 77 million in 2000 to over 103 million in 2016, the amount of water available per person each year dropped from 1,907 cubic meters to just 1,400 cubic meters — among the lowest in Asia, well below the Southeast Asian average of 3,668 cubic meters and roughly one-third of the global average of 7,045 cubic meters.

Water quality is also deteriorating. Of the country’s 623 classified water bodies, only a limited number meet the highest potable standard (Class AA). About 36 percent fall under Class C, primarily suitable for fisheries, while 33 percent are rated Class D, requiring substantial treatment before they can be used for drinking.

GROUNDWATER RELIANCE, RISING EXTRACTION

A key concern raised in the study is the country’s heavy and growing reliance on groundwater — the main source of supply for most water districts nationwide.

Globally, groundwater accounts for about 99 percent of liquid freshwater and supplies roughly half of domestic water use. In the Philippines, extraction has steadily increased, rising by an average of 3.8 percent annually from 2014 to 2023. The water supply industry itself showed an increase of 11.2 percent from 2022 to 2023.

A sharp 17.7 percent jump was recorded from 2019 to 2020, driven largely by mining, manufacturing, quarrying, and construction. During this period, groundwater use far exceeded surface water use in both volume and growth rate.

Overdependence on aquifers can increase the risk of saline intrusion in coastal areas, land subsidence, falling water tables, and long-term deterioration of water quality. In 2018, total water withdrawals peaked at 92.3 million cubic meters, with water stress reaching 28.21 percent — highlighting how demand is increasingly pressing against available supply.

DEMAND OUTPACES SUPPLY

The impact of these system constraints is evident among the country’s 532 water districts. From 2019 to 2024, average annual demand reached 10.6 million cubic meters, while effective supply stood at only about 7 million cubic meters — resulting in a persistent 3.6 million cubic meter deficit.

Luzon recorded the largest shortfall, with an average negative balance of 5.8 million cubic meters from 2019 to 2024. The highest average water deficit was in Region 3 (Central Luzon) at 14 million cubic meters. In the Visayas, the average negative water balance was 2.7 million cubic meters, while Mindanao recorded a deficit of 1.9 million cubic meters.

Coverage rates tell a similar story. The study found that overall coverage for Luzon water districts from 2019 to 2024 was just 63 percent — well below the 85 percent benchmark considered ideal for water district performance. In the Visayas, coverage stood at 68 percent, while Mindanao performed slightly better at 73 percent. Only Region 9 (Zamboanga Peninsula) consistently exceeded 95 percent coverage.

Many communities continue to rely on shared sources such as public wells or springs for domestic use. According to 2022 data from the Annual Poverty Indicators Survey, 54.3 percent of Filipinos get their drinking water from water refilling stations, while only 24.2 percent rely on piped water.

The study also found that water districts in Luzon source almost 98 percent of their water from wells, while those in the Visayas use wells for about 60 percent of supply, supplemented by springs and surface water. In Mindanao, districts rely on both wells and springs, with the Bangsamoro Autonomous Region drawing a larger proportion from springs.

GOVERNANCE, UNEVEN RISK, AND CLIMATE EXTREMES

The supply deficits faced by water districts are not driven by resource constraints alone — they are also shaped by governance and institutional complexity. Water governance in the Philippines is fragmented, with around 30 public sector agencies, national and local, sharing responsibilities over water quality, watershed management, irrigation, hydropower, sanitation, flood control, research, and water supply.

Weak coordination and overlapping mandates can delay permitting, infrastructure investment, and service expansion, contributing to persistent supply shortfalls at the local level.

Water availability is also unevenly distributed across the country. A 1998 Japan International Cooperation Agency (JICA) study identified Cagayan Valley (Region II), Central Luzon (Region III), Southern Tagalog (Region IV), and Central Visayas (Region VII) as the regions most likely to face water deficits.

Major urban centers including Baguio, Metro Manila, Metro Cebu, and Davao have already been identified as water-stressed, with vulnerabilities further intensified by climate extremes like El Niño and La Niña.

TARIFFS, LOSSES, AND FIXES BEFORE 2030

The study also examined water tariff structures across selected water districts. Most, if not all, water districts use increasing block tariffs (IBTs), where rates rise with consumption volume.

Among the districts reviewed, the Obando Water District in Bulacan had the highest minimum monthly charge at PHP 367, while Metro Cebu Water District had the lowest at PHP 157. Cagayan de Oro Water District charged PHP 218 per month, and Davao City Water District charged PHP 214.20.

However, the study warns that IBT structures can inadvertently penalize the poorest households, particularly those sharing water connections, as their combined consumption pushes them into higher-priced blocks.

As an alternative, the study cites research proposing a Uniform Price with a Rebate (UPR) model, which can achieve the same social and financial goals as IBTs without their structural flaws.

Non-revenue water — system losses from leaks, theft, or unbilled usage — also significantly worsens supply deficits. The study applied an estimated 30 percent NRW rate in calculating effective supply, which reduces actual water available to consumers and widens the gap between demand and delivery.

A 2009 World Bank analysis of 35 water districts also revealed a counterintuitive finding: despite their potential for economies of scale, integrated water systems actually underperformed compared to non-integrated ones, driven by higher fixed costs and greater operational inefficiencies. Residents in integrated districts faced higher water costs, while these districts experienced slower growth in new service connections.

“Securing the Philippines’ water future requires shifting from fragmented, source-specific responses toward integrated planning, stronger monitoring, and better-supported water service providers,” Agbon said.

RECOMMENDATIONS

The study recommends establishing integrated source-planning units at the regional or provincial level to coordinate groundwater and surface-water allocation, protection, and emergency response. It also calls for scaling a national groundwater monitoring network with standardized data reporting and open access for water districts and researchers.

Other recommendations include mandating source-protection zones around intakes and critical recharge areas, creating blended finance windows combining public grants with low-cost loans for infrastructure upgrades and leak reduction, and investing in capacity-building for water district operations including asset management, hydrogeology, smart metering, NRW reduction, and financial modeling.

With less than five years remaining to meet national water supply and sanitation targets under the Philippine Development Plan 2023–2028 — which aims for 97.48 percent of Filipino families to have access to safe water by 2028 — the study underscores the need to strengthen water districts’ capacity to expand coverage, improve system efficiency, and manage groundwater resources sustainably.

Improving service reliability will require closer institutional coordination, targeted infrastructure investments, and pricing and financing mechanisms that support both affordability and long-term system sustainability, the study said.

The Philippines is organized into 12 Water Resources Regions, with a hydrological network comprising 623 recognized water bodies including 283 major principal rivers, along with various lakes, bays, and smaller river systems.

The country’s largest river basins include the Cagayan, Mindanao, Agusan, and Buayan-Malungon.

Local Water Districts, created under Presidential Decree 198 or the Provincial Water Utility Act of 1973, are government-owned and controlled corporations authorized to operate, manage, and maintain water systems in cities, municipalities, and provinces nationwide.