Mitigating effects of flooding
Earlier this year, the Philippine government had sought financing for a $500-million flood control project in Metro Manila.
According to an Inquirer report, the said project would include “constructing new and modernizing existing selected pumping stations and their supporting infrastructure; improving solid waste management practices within the vicinity of drainage systems served by the selected pumping stations, and supporting the resettlement of project affected people.”
Citing project documents, the Inquirer report stated that the project would focus on 56 potentially critical drainage areas with an approximate land area of 11,100 hectares or over 17 percent of the total area of Metro Manila. This will include an area covered by new pumping stations of about 2,900 hectares, with a total population of about 970,000 people or about 210,000 households.”
The reason behind this proposal is more than obvious: the Philippines is “highly vulnerable to natural disasters with exceptionally high exposure to cyclones and floods.”
“The country, on average, is struck by 20 cyclones every year causing widespread flooding across the country including Metro Manila,” it added.
A 2015 study by the government’s Nationwide Operational Assessment of Hazards (NOAH) said that “humans have altered the landscape in the metropolis which has grown rapidly but with poorly planned urbanization.”
It broke down the factors that cause Metro Manila flooding, including encroachment of concrete surfaces, densification of buildings and residential areas, silting of riverbeds and canals, obstruction of waterways by informal settlers, clogging of floodways by garbage and reclamation of coastal land.
Many parts of the metro were also subsiding because water that occupies the ground below is extracted by humans faster than it is replenished by nature, Project Noah executive director Alfredo Mahar Lagmay was quoted as saying.
And when heavy rains hit Metro Manila, which sits on a flood plain for three rivers—the Marikina, Napindan and Pasig rivers—it sinks even further, such as in 2012 when nonstop rains hit the metropolis.
Among the devastating typhoons that had hit Metro Manila include Typhoon Ondoy (international name: Ketsana )in 2009, which killed 464 people, flooded 239 barangays in the metro, with Marikina City affected the most, government data showed. Flood waters ran from knee to rooftop deep.
About 37 roads were not passable to light vehicles due to flooding at the height of the typhoon. Cost of damage to infrastructure alone stood at P4.3 billion, including school buildings and health facilities.
In 2015, the Metro Manila Development Authority (MMDA) identified 23 flood-prone areas which included major thoroughfares such as the streets of España, Buendia, Osmeña Highway, Quezon Avenue, C-5 and Edsa.
Flood control projects
This is perhaps why flood mitigating projects will always be high on the agenda of every administration.
The Duterte administration’s ambitious infrastructure projects under its “build, build, build” strategy include flood control measures for Metro Manila. Among these projects are the P7.5-billion Pasig-Marikina river channel improvement project phase three, and the P359-million Mandaluyong drainage project along Maysilo Circle.
Under the Aquino administration, 96 flood-mitigating projects under the P5-billion high-impact flood control program were completed in 2015 for three regions, including Metro Manila.
Sources: Inquirer Archives, blog.noah.dost.gov.ph, build.gov.ph, dpwh.gov.ph
Subscribe to INQUIRER PLUS to get access to The Philippine Daily Inquirer & other 70+ titles, share up to 5 gadgets, listen to the news, download as early as 4am & share articles on social media. Call 896 6000.