The editorial “Reforestation is key” (11/20/20) observed how even if the amount of rainfall brought by Typhoon “Ulysses” was only a third of Typhoon “Ondoy’s” in 2009, the water level in Marikina River still breached the 21.5-meter depth during Ondoy. The apparent narrowing of the Marikina River stretching between the outlying barangays of Banaba and Ampid, San Mateo, Rizal, or thereabouts, could partly be the culprit.
The newly built concrete dikes on the opposite banks along the said stretch perched with concrete “biking and jogging lanes” (construction of the lanes is still ongoing on the upstream side) resulted in the narrowing of the river and the consequent decrease in its carrying capacity. The elevated dikes or retaining walls were rendered less or ineffective to contain the rising water from spilling over to the outlying areas and subdivisions at the height of Ulysses because of the river’s resultant contraction. The project could have even contributed to the river’s precipitate swelling.
Because of their impact to lives and properties, not to mention their huge financial costs, flood control projects should not be left to engineers and, more so, to politicians alone, but planned and designed in consultation with hydrologists, geologists, environmentalists, and other experts in the geosciences. They should be undertaken beyond what columnist Richard Heydarian termed as “performative populism.”
DIOSDADO V. CALONGE, dvccalo@yahoo.com