IF PUMP systems of the metropolis are fixed, will devastating floods sinking Manila and nearby areas every year finally stop?
To reduce heavy flooding in the metro especially during wet season, 1.6 billion pesos was released by the Department of Budget and Management last March for the repair and upgrade of 12 water-pumping stations.
According to Budget Secretary Florencio Abad, the rehabilitation of selected pumps will help ease flooding in Metro Manila and suburbs.
“The recently approved funds will allow us to enhance the capacity of our pumping facilities and upgrade them as needed, well before the rainy season,” Abad said on the department’s website.
Michael Doce, pumping stations and floodgates division engineer of the Metro Manila Development Authority (MMDA), said the rehabilitation was necessary to combat flooding.
“Flooding will be lessened because the pumping capacity of the water pumps will be improved,” Doce told the Varsitarian in an interview.
These facilities, which have a diameter ranging from one to 1.6 meters and pumping capacity of 2.5 to seven cubic meters per second, drain water from low-lying places and remove sewage from industrial areas. The’yre supposed to do the work when drainage cannot be accomplished by the pull of gravity alone.
“Water pumping stations are delegated to low-lying areas,” Doce said. “They pump water from an estero to a body of water, like the Manila Bay, during the rainy season or when there is a typhoon.”
High tide, or when a body of water reaches its highest point of elevation, also stimulates the driving action of pumps, he said.
“Before high tide, the gate of the water pump is closed so that the main land will not be affected. The pump flushes water out so there will be impounding in the retarding area. This way, flooding can be prevented because there will be a place for incoming water,” Doce explained.
Pumping stations up for rehabilitation are in Libertad, Quiapo, Tripa de Gallina, Pandacan, Valencia, Binondo, Aviles, Paco, Makati, Sta. Clara, Balete and Arroceros.
Old, clogged
Aside from perennial flooding, one of the main reasons why pumping systems needed to undergo rehabilitation was that the facilities have exceeded their ideal life span.
“Each equipment has its own life span. In cases where the equipment exceeds its service life, its capacity and efficiency deteriorate,” Doce said.
The pumping stations are now about 40 years old, exceeding the ideal life span of 25 to 30 years. They were designed in the late 1960s to have a runoff coefficient of 60 percent. The runoff coefficient pertains to the proportion of rainwater that reaches the streams along with liquefied and suspended materials. The rest are absorbed by the soil.
“Nowadays, more domestic water and wastes are going directly to canals, as there had been a rapid increase in the number of cemented areas and high-rise buildings,” he said, adding that pumping stations are now falling short in handling floodwaters and wastewater because of lack of absorption.
Rehabilitation will also increase the capacity of pumping stations, to prepare for strong weather disturbances such as Tropical Storm Ondoy that killed 464 people and damaged P11 billion worth of property in 2009.
“Each pumping station was designed to have a specific pumping capacity and in order to contain strong typhoons, bigger pumping stations with larger capacities must be built,” Doce said. “Our pumping stations were only designed to encapsulate 80 to 90 millimeters of rain per hour, but Ondoy’s was around 500 millimeters.”
Aside from old age, garbage has also contributed to the inefficiency of water-pumping facilities. “Garbage may cause clogging in the pump. In cases where solid wastes get stuck, the mechanical seal of the pump will malfunction, causing leakage and putting a halt to the operation of the pump,” Doce said.
Doce said proper collection and disposal of waste still play a key role in preventing flooding.
“The local government units should religiously and efficiently collect wastes, because there is a tendency that uncollected garbage gets disposed of in drainage canals,” the MMDA engineer said.
He said citizens should be aware of the poor conditions of pumping stations and how these facilities are being damaged by improperly disposed garbage.
“For people to further understand the reason why garbage must be disposed of properly, they can go to the location of the water pumping stations so they can see how the facility works and how garbage and solid wastes cause damage and problem to the equipment,” Doce said. Altir Christian D. Bonganay
