Mandatory rainwater system in houses to reduce flooding sought

MANILA, Philippines —  With the regular recurrence of dry spells, it is time to make the installation of a rainwater collection system (RCS) “mandatory” in all buildings, residential or commercial, if only to mitigate flooding, according to a senior administration lawmaker.

“The global extreme weather conditions apparently due to climate change prompted the idea calling for the mandatory RCS installation in all residential, commercial and institutional buildings that would be built in the future,” Surigao del Norte 2nd District Rep. Robert Ace Barbers said.

Barbers urged his colleagues in the House of Representatives to approve House Bill 4837 that he authored, mandating an RCS in all new residential, commercial and institutional buildings, particularly in densely populated areas of the country.

Barbers, who chairs the House committee on dangerous drugs, said the primary objective of his bill was to “promote sufficient potable water supply in times of calamities or weather disturbances like El Niño and reduce floodings in times of La Niña in the country.”

He explained that an RCS shall mean a facility designed to capture, retain and store rainwater flowing off a building, parking lot or any other man-made, impervious surface, for subsequent onsite use.

The RCS concept is not new in the country, particularly in rural areas with limited water supply, where pipes or diverters connected to big barrels are used to collect and store rainwater.

“But in urban or densely populated areas like Metro Manila, people put little to no emphasis on rainwater collection due to the presence of service companies, like Maynilad and Manila Water that provide stable and abundant water supply,” Barbers said.

With the onset of El Niño, however, the Mindanaoan legislator said water in Angat Dam continues to evaporate and decline due to extreme heat and may soon cause water service interruptions considering a possibly great demand but low supply of the basic commodity.

Barber’s bill mandates the owner or developer of new residential, commercial and institutional buildings to include in its building plan an RCS, while local government units (LGUs) and the Housing and Land Use Regulatory Board are mandated to deny construction permits of such edifices that are without an RCS design or plan.

The Department of Public Works and Highways, through its concerned attached agencies, will be required to install RCS to all new government buildings, and shall supervise the filtration and purification process to ensure that the stored rainwater is safe for drinking.

Barbers said private institutional buildings such as private schools and universities, including large commercial establishments like malls, supermarkets and companies, will be required to install rainwater filtration facilities connected to an RCS for onsite use as potable water.

Property owners who comply with the RCS installation will be extended a 10-percent tax credit of their total real property tax, but not exceeding P10,000.

Concerned LGUs, through their engineering office, shall inspect and issue certifications, which will be used by the property owner as proof for tax credit purposes, on RCS installation compliance.