Man planting mangrove

Planting mangroves to save a province from drowning

Mangroves may not be a part of a beachcomber or surfer’s vision of a coastal paradise. Nonetheless, these tropical coastal forests play a crucial role in favor of human habitation, especially during typhoon season.

Mangroves—shrubs or small trees that grow in coastal saline or brackish water—move carbon dioxide “from the atmosphere into long-term storage” in greater quantities than other forests, making them “among the planet’s best carbon scrubbers” according to a NASA-led study based on satellite data. Furthermore, the aerial roots of these “multi-taskers in the world of ocean wealth”, as described by oceanwealth.org (https://oceanwealth.org/accounting-for-mangroves-in-flood-protection/), “retain sediments and prevent erosion, while the roots, trunks and canopy reduce the force of oncoming waves and storm surge and thus reduce flooding.”

According to the journal “BioEcology and Geography”, the total mangrove forest area of the world in 2000 was 137,800 square km—roughly the size of the US state of Arkansas—spanning 118 countries and territories.

That number is dwindling, however. According to a World Bank blog posted by Michael Beck and Glenn-Marie Lange in September 2017 (https://blogs.worldbank.org/eastasiapacific/mighty-mangroves-of-the-hilippines-valuing-wetland-enefits-for-risk-reduction-conservation), 19% of the world’s mangroves were lost between 1980 and 2005.

In the Philippines, the sad story hasn’t been that different. In an August 2018 story in the Business Mirror (https://businessmirror.com.ph/2018/08/05/worlds-mangroves-struggling-to-survive/), Silliman University Marine Biologists Frances T. Bengwayan and Marjho Cardoza said in their report “Current Status and Threats of Philippine Mangals”: “Of the estimated 250,000 hectares of mangrove forests, only 80,000 hectares are left,” a result of a mangrove-depletion rate of as much as 8 percent annually for the past 10 years.

And what would a nation that sits right smack in the middle of the path of about 20 typhoons a year look like without mangroves? Beck and Lange put it bluntly: “Without mangroves, flooding and damages to people, property and infrastructure would increase annually by approximately 25%.”

That sort of increase is even more alarming when one considers the amount of destruction flooding has caused relative to other natural calamities the country has suffered. “Between 2005 and 2015, 56% of property damage in the Philippines was due to typhoons and storms, and another 29% due to floods,” Beck and Lange revealed.

On the flipside, if we had much more of these mangroves, the benefits to human habitation and livelihoods would be immense. Beck and Lange wrote further: “Across the Philippines, mangroves reduce flooding to 613,000 people annually, of whom more than 23% live below poverty, and avert more than $1 billion in damages to residential and industrial property. If mangroves were restored to their 1950 distribution, there would be additional benefits to 267,000 people annually, including 61,000 people below poverty, and $450 million in annual averted damages.”

These figures were probably foremost in the minds of executives of the country’s largest company when they decided that planting mangroves in flood-prone Bulacan province was one of the best ways to avert an impending disaster.  

Last July 28, San Miguel Corp (SMC) started planting 25,000 mangroves on 10 hectares of coastal area in Hagonoy, Bulacan—the first of a total 190,000 mangroves to be planted in over 76-hectares in Bulacan and Central Luzon.

The initiative is part of a massive, wide-ranging plan to address perennial flooding in the province, ahead of construction of the country’s newest and largest international gateway just north of Metro Manila.

“This project is a major component of our strategy to help solve flooding in Bulacan once and for all,” said SMC president Ramon S. Ang.

“This effort is part of our larger flood-mitigation strategy for Bulacan. The first is our P1-billion plan to dredge and clean-up the Tullahan-Tinajeros River system, which began earlier this year. This involves cleaning major river systems and tributaries that have been clogged up with garbage and sediment for so many decades, preventing flood waters from draining into the Manila Bay,” Ang said.

“But apart from cleaning and clearing major waterways, the planting of mangroves in strategic areas is also important, because it acts as the first line of defense against inundation for those living along the shorelines, whenever there are storms or strong tides. They are also key to maintaining the marine eco-system and water quality, as they are a natural habitat for marine species,” he added.

In Hagonoy, Ang said the plan is to plant 10 hectares of coastal area in Bgy. Tibaguin with 25,000 mangrove seedlings, in order to help protect locals from floods brought on by the rainy season, tidal floods, and waters coming from the Pampanga basin.

Hagonoy Mayor Raulito Manlapaz Sr led the planting of an initial 8,000 mangrove seedlings over an area of three hectares. The next planting activity is scheduled for November, and all 10 hectares are expected to be completed within the year.

Manlapaz was joined by regional officials of the Department of Environment and Natural Resources (DENR), other national and local officials, representatives from SMC, and volunteers.

It was DENR that identified Hagonoy as one of the priority areas for mangrove-planting. “Hagonoy is one of the lowest-lying towns in Bulacan that perennially experience floods. But this is just the first of many areas. We are working with the DENR, who is helping us identify critical areas. The goal is to cover 76 hectares of coastal area all over Central Luzon, and plant a total of 190,000 mangrove saplings,” Ang said.

Prior to the mangrove planting and start of the Tullahan River rehabilitation and cleanup—which is also a key component of government’s major effort to clean up the Manila Bay—SMC said that it had consulted both local and foreign experts on how to address Bulacan’s flooding problem.

This, even before it begins actual work on the new Manila international Airport project, to be built in Bulakan, Bulacan.

“It’s all part of the airport development master plan. We will not be investing over P700 billion if flooding and environmental concerns are not addressed. This airport will not only be modern, sustainable, and game-changing for the economy and the people, it will also bring a lot of good for Bulacan, its local industries, and neighboring provinces–one of which is it will help solve flooding,” he said.

“There is no one solution to flooding. It is a combination of solutions, and is a continuous process. That is why for the Tullahan River project, we decided to just buy all the heavy equipment—dredging machines, barges, dump trucks–and train our people to operate the machines themselves. Solving flooding will go beyond the five-year period that we committed to clean-up Tullahan. It will need maintenance. All our efforts are for the long-term and will come at no cost to government,” Ang said.

Ang added: “Despite the coming of the CoViD-19 pandemic, we said that we will continue all our major infrastructure and expansion projects. I’m proud to say that our commitment to the people of Bulacan to help solve their flooding problem also continues.”