DOST: Conserve mountains, build retention basins to address flood woes

The Department of Science and Technology (DOST) on Thursday raised suggestions to help address the country's long-standing problem of flooding in times of heavy rains.

During the House committee on appropriations' deliberations on DOST's proposed P28.77-billion budget for next year, Secretary Renato Solidum Jr. underscored the need to have water retaining structures or series of dams in Metro Manila and other areas where rainwater can be stored temporarily.

"Even in other areas na hindi kaya ng dam kung flat ang area—kung may bundok okay—[the solution] is to have water retention basins. Ibig sabihin, temporarily store the water in some dams or basins and then release it slowly so that the water will not be very high," Solidum said.

(Even in other areas where the dams couldn't be built because the area is flat [the solution] is to have water retention basins. This means that we should temporarily store the water in some dams or basins and then release it slowly so that the water will not be very high," Solidum said.

The increasing amount of rain due to climate change, topped with the urbanization of areas, Solidum said, "will really cause a lot of flooding" unless structures that will manage the flow of water will be built.

"The second issue will be land use. If we put concrete or asphalt over our surfaces, then essentially, the water will not seep through the soil and [eventually] will make the runoff of the water faster towards drainages, kanal, or the ilog (will make the runoff of the water faster towards drainages, canals or rivers)," he said.

"So nako-concentrate ngayon sa mga ilog and drainage, at ang drainage naman natin ay sinauna, 'di naman sapat pa. So kailangang ayusin 'yan. At mababa ang mga lugar—we have settled in areas that will really be flooded kahit maliit lang ang ulan," he added.

(So the water is concentrated on rivers and drainage, but our drainage systems are old and not enough. That needs to be fixed. There are areas that are also low—we have settled in areas that will really be flooded even if there's only a little rain.)

Solidum also stressed the importance of conserving mountains by not building residential areas on it.

"The overall solution, of course, is engineering intervention, but we also need to retain green spaces up there in the mountain," Solidum said, adding that, "Kasi 'pag puro subdivision ang bundok, didiretso lang sa Metro Manila ang tubig (if there are many subdivisions on the mountains, the water will just go straight to Metro Manila)."

The DOST chief also called on the passage of the National Land Use Act to help with addressing the flood problems.

If enacted into law, the National Land Use Act will provide a framework on proper utilization and management of land resources in the country.

The proposed law also seeks to create the National Land Use Commission under the Office of the President, the highest policy-making body that would handle the management and planning of land use, and resolve land use policy conflicts.

Aside from these, Solidum also stressed the need to have an integrated river basin management and to fix the drainage system in the country.

Rivers need to be dredged from time to time, Solidum said, in order not to get silted.

Band-aid solution

The Science and Technology chief, however, emphasized that dredging operations are only a "band-aid solution" if it is being done without accompanying measures to solve the problem.

"If it's done alone, it's band-aid. But you need to be dredging rivers because with time, rivers will be silted. So even if you have dams but you don't dredge, then the capacity of that river to accommodate a certain volume will get smaller and it will overflow," he said.

Severe Tropical Storm Enteng and the Southwest Monsoon (Habagat) have recently brought floods and swollen rivers in the country, mostly in Luzon areas. In July, Typhoon Carina and the enhanced Habagat also brought intense rains and flooding.

For his part, President Ferdinand "Bongbong" Marcos Jr. had ensured that his administration was exhausting innovative measures to address the country's flood problems. — VDV, GMA Integrated News