DAVAO CITY (October 22) — Filtering canal water does not necessarily make it safe to drink, a Southern Philippines Medical Center (SPMC) emergency doctor warned, as the looming El Niño threatens to intensify heat and water shortages that could expose communities to dehydration and waterborne diseases.
Dr. Honey Christine Dasmariñas, medical officer of SPMC’s Health Emergency and Disaster Management Unit (HEDMU), advised Dabawenyos against using filtered canal water, even as the government prepares to distribute portable filtration kits to communities facing water shortages.
“I won’t advise people to use canal water that is filtered pa siya,” Dasmariñas said during the Kapehan sa Dabaw media forum on Monday, October 19.
She said contaminated water can cause acute gastroenteritis, cholera and typhoid, making safe water storage and access to reliable drinking-water sources critical during prolonged hot weather.
The warning comes days after Department of Social Welfare and Development (DSWD) Secretary Rex Gatchalian demonstrated a portable water filtration kit during a Palace briefing on October 14. In a demonstration aired by Radio Television Malacañang, Gatchalian poured soil into water before passing it through the device.
The DSWD plans to distribute the kits free to communities experiencing water shortages due to El Niño, beginning with areas under a state of calamity, Gatchalian said.
He cited a Department of Health certification indicating that the filter membrane can remove 99.999 percent of contaminants and said the kit can filter water from deep wells, springs, rainwater and streams.
However, the filtration claims do not establish that every water source is safe to drink after treatment. Dasmariñas specifically advised against drinking filtered canal water and suggested considering other sources, such as cisterns.
Safe water, heat precautions
Dasmariñas urged households to store reserve water in clean, covered containers to reduce the risk of contamination. She also advised people to drink water regularly rather than waiting until they feel thirsty.
“Even though we are not thirsty, we need to drink lots of water regularly,” she said, warning that excessive heat can lead to dehydration, heat exhaustion and heat stroke.
Adults generally need eight to 10 glasses of water daily, she said, with greater fluid intake often needed during hot weather because of increased sweating.
For outdoor workers, she recommended taking breaks in shaded or cooler areas when they begin feeling overheated, drinking water regularly and wearing loose, breathable clothing.
“Once you feel the heat in your body, then you have to go to a cooler shade or cooler area,” she said.
SPMC reservoir lasts three to five days
Dasmariñas said an assessment conducted by her team the previous month estimated that SPMC’s water reservoir could sustain the hospital for around three to five days.
She cautioned, however, that she could not provide the reservoir’s specific capacity.
The estimate highlights the importance of water preparedness for health facilities, where adequate supplies are essential for patient care and hospital operations as dry conditions threaten water availability.
Vulnerable groups face greater risks
Older adults, children, pregnant women and people with pre-existing conditions, including asthma and kidney problems, are particularly vulnerable during El Niño, Dasmariñas said.
People with kidney problems and hypertension may face additional concerns when excessive heat and sweating contribute to dehydration.
The Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) earlier warned that El Niño would intensify in the last quarter of 2026 and persist through the first half of 2027.
PhilHealth has also said its coverage includes heat-related illnesses such as heat stroke and dehydration, as well as typhoid and acute gastroenteritis.
As water shortages loom, the immediate public-health challenge is not only securing enough water but ensuring that households can safely drink what they store or obtain from alternative sources.
