PAGASA to activate flood-warning sirens PDF Print E-mail
Monday, 07 July 2014 11:35



Government’s weather agency raised Philippine disaster risk reduction (DRR) to a new level.

Aside from issuing advisories on possible flooding, State-run weather agency Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) will warn communities about such looming threat by also sounding the alarm - literally.

“We enhanced our early warning system (EWS) with sound using sirens so people can be better aware of and prepare for possible flooding in their areas and evacuate to safer ground if necessary,” said PAGASA senior hydrologist Max Peralta who’s helping spearhead the undertaking.

He noted PAGASA itself will activate the sirens using computers if its real-time water elevation data warrant such action.

“It’s a first for PAGASA,” he said.

Such became possible through a grant Korea InternationalCooperation Agency (KOICA) provided PAGASA for the project’Establishment of an Early Warning and Monitoring System for Disaster Mitigation in Metro Manila.’

Initially totaling some PHP150 million, the grant fundedestablishment of the project’s data collection, flood forecasting and early warning systems covering Metro Manila and nearby Rizal province.

The grant also funded establishment of a radio communication network for data transfer and flood warning dissemination.

Peralta recalled KOICA extended the grant following onslaught of record flooding in Metro Manila, nearby Rizal province and other areas during storm ‘Ondoy’ (international name ‘Ketsana’) in 2009.

“KOICA inquired about what assistance it can offer in the wake of death and destruction from ‘Ondoy’ and discussions on the matter led to the project’s creation,” he noted.

Downpour from ‘Ondoy’ resulted in disaster as deadly flooding submerged and crippled communities in several parts of Metro Manila - the Philippines’ leading urban center - as well as Rizal and other areas, fueling clamor for and action on DRR.

UNISDR said disaster is a “serious disruption of the functioning of a community or a society involving widespread human, material, economic or environmental losses and impacts, which exceeds the ability of the affected community or society to cope using its own resources.”

Loss of life, livelihood and property as well as injury, disease, destruction of assets, loss of services, economic disruption and environmental degradation are among impacts of disasters, noted UNISDR.

EWS is a disaster mitigation measure that enables local authorities and communities to plan for and act on flooding and other hazards so the possibility for loss or destruction from onslaught of these can be reduced.

UNISDR noted hazard is “a dangerous phenomenon, substance, human activity or condition that may cause loss of life, injury or other health impacts, property damage, loss of livelihoods and services, social and economic disruption, or environmental damage.”

Latest available data show the Jesuits began operating in 1865 the first EWS in the Philippines.

Since then, the country’s EWS covered indigenous and conventional means of coping with floods.

Peralta highlighted need for enhancing PAGASA’s EWS, noting flooding has been occurring nationwide over the ages due meteorological factors affecting the Philippines.

Aside from causing death and destruction, he said studies show flooding nationwide cost government an average PHP15 billion annually or 0.5 percent of Philippine GDP in direct damages.

Citing a 2010 study, he also said floods’ indirect and secondary impacts further increase such costing.

“We can’t afford to increasingly incur flooding-related deaths, destruction and economic loses,” he said.

He believes continuous improvement of EWS will help lower the risk for disasters from flooding.

UNISDR said disaster risk is “the potential disaster losses, in lives, health status, livelihoods, assets and services, which could occur to a particular community or a society over some specified future time period.”

DRR involves reducing disaster risks “through systematic efforts to analyze and manage the causal factors of disasters, including through reduced exposure to hazards, lessened vulnerability of people and property, wise management of land and the environment, and improved preparedness for adverse events,” UNISDR continued.

Survey for the KOICA project’s basic design commenced in November 2010.

Installation of equipment needed for the project reached completion in February 2012.

PAGASA and KOICA afterwards made adjustments to the entire set-up to help minimize possibility of problems occurring during its operation.

“Already installed are 10 rain gauge stations, 10 water level stations and four automatic weather stations in Metro Manila and Rizal,” said Peralta.

He said PAGASA and KOICA likewise installed 20 warning posts with sirens and established six disaster risk reduction offices there.

PAGASA data show locations for the warning posts are Rizal’s Rodriguez (three units), San Mateo (two units), Rosario (two units) and one unit each in Wawa Dam, Burgos, Delacosta Subd., Nangka, Tumana Bridge, Sto. Niño, Marcos Highway, People’s Park, Mercury Ave., San Juan School, Guadalupe, Napindan and Fort Santiago.

Peralta said the stations gather data on actual weather conditions in areas these cover.

He noted such stations use the project’s radio communication network to transmit the data to PAGASA’s central office in Quezon City.

“Our central office receives the data in real time every 10 minutes so when water rises to threshold levels in any of the waterways we’re monitoring, we’ll know that and activate the siren there to warn people about flooding danger in their area, giving them time to react accordingly,” he noted.

Such threshold levels vary among the waterways but all indicate extent to which the waterways’ water already rose at a given time, he said.

“We established the threshold levels for some of the waterways and adapted those LGUs concerned already set in others,” he noted.

The LGUs generally indicate such levels by painting corresponding marks on posts.

Water reaching the lowest threshold level indicates need for people to be aware of looming flood danger in their area, Peralta said.

People must already prepare for such threat if water reaches the next higher threshold level, he noted.

He said evacuation to safer ground is in order if water already reaches the highest threshold level, he continued.

“We assigned a one-minute sound for each of the three thresholds so people can distinguish one level from the other and know what’s already happening in their area,” he said.

To make the warnings more understandable, he said people will also hear voice recordings that inform them about the danger they face.

“People will hear the sound and corresponding voice recording once we activate the siren in their area,” he said.

According to Peralta, the sounds and voice recordings will replay continuously until PAGASA deactivates its sirens.

The sirens can be activated and deactivated from PAGASA’s central office with a touch of the button, he noted.

Apart from test runs, Peralta said PAGASA hasn’t yet officially activated any of the sirens.

“Rainfall so far has been insufficient to raise water level to even the lowest threshold,” he said.

He assured the sirens are ready for use when needed.

The stations are also already furnishing PAGASA central office real-time data on weather-related conditions in respective areas of coverage, he noted.

“We’re prepared for full-blast operation,” he said.

As its counterpart for the project, Peralta said PAGASA earlier commenced conducting an information campaign aimed at orienting LGUs concerned about the sirens and other components of the project.

The LGUs must brief respective constituents about the sirens and meaning of sounds from these, he noted.

“We’ll provide technical assistance to such LGUs,” he said.

Among PAGASA’s existing services are providing hydro-meteorological information.

PAGASA relays such information through its flood bulletins for monitored major river basins, reservoirs and dams.

The agency also issues general flood advisories for non-telemetered river basins as well as hydrological forecasts during non-flood watches.