INSTEAD of constructing new drainage systems, the Department of Public Works and Highways (DPWH) Sixth District Engineering Office is enhancing the capacity of existing culverts and drainages in all flood-prone barangays to mitigate flooding in Mandaue City.
The DPWH has begun improving existing drainage infrastructure instead of constructing new structures. This measure, implemented in coordination with the Mandaue City Engineering Office, aims to address the worsening flooding problem amid the rainy season.
District Engineer Gumer Castillo said in a phone interview on Wednesday, June 11, 2025, that their focus is on boosting the water-carrying capacity of culverts and drainages by removing obstructions and silt.
“The enhancement we are doing aims to increase the volume of water these drainages can handle. Even though we haven’t built new drainage structures yet, we are cleaning the existing ones thoroughly to expand their capacity and ensure smoother water flow during heavy rains,” Castillo said in a mix of Cebuano and English.
Flood-prone barangays include Tipolo, Subangdaku, Ibabao-Estancia and Banilad.
Castillo said the city already has several existing culverts, but he could not provide a specific count.
Cleaning culverts
Maintenance teams have been deployed to clean blocked culverts and drains clogged due to years of neglect or improper waste disposal. Several drainage sections have already been improved.
However, Castillo said a major issue remains unresolved: the outfall of drainage water into the sea.
“During high tide, the water cannot flow out because it gets stuck. There are existing proposals on how to address this, but these still need to be discussed with the local government,” he said.
He emphasized that well-designed flood control structures will not work without public cooperation.
“The culvert will only be effective if people take responsibility for their waste. Even if the structure is good, if people are negligent, it still won’t be effective,” he said.
Larger flood control infrastructure under the master plan will require further discussions with the City Government, especially for installing additional culverts in strategic locations.
There is also a proposal to widen culverts in areas near rivers and creeks to help floodwaters drain faster.
Inventory
Castillo said the DPWH’s planning, maintenance and construction divisions have been tasked with conducting a two-week inventory of all culverts and drainage systems starting this week.
“This will help us assess whether these systems are still in good condition or if they need to be replaced or further enhanced,” he said.
Funding for these projects, he said, will be requested either from the City Government or from national agencies.
Meanwhile, City Engineering Office Building Inspector Joel Sayson, who oversees the Maintenance Division, echoed Castillo’s remarks. He said narrow drainage systems are one of the main causes of flooding in Mandaue City, worsened by garbage accumulation and poor community discipline.
Sayson said the City should begin adopting wider drainage systems to handle larger volumes of water.
On Wednesday morning, personnel from the DPWH and City Engineering Office conducted a drainage cleanup operation in Barangay Tipolo, one of the most flood-prone areas in the city.
“The drainage system along this road leads to the outfall at Tipolo Creek, but the water cannot flow properly because it is blocked by trash and mud,” he said.
Garbage
During the operation, about 10 cubic meters of garbage were extracted, much of it stuck around the manhole near the Tipolo Shipyard. The manhole, which measures 30 inches in diameter and is 5 to 6 feet deep, should ideally be at least 8 feet deep to allow floodwaters to drain quickly during heavy rainfall.
“The drainage really needs to be widened because the water volume during rain is too much. It can still subside, but not fast enough mainly due to garbage,” Sayson said.
The operation sought to address flooding caused by non-biodegradable waste such as plastic bottles, cups, and other debris.
Sayson said the garbage removed would be transported to the city’s dumpsite. He stressed the need for regular cleanup operations while major drainage projects remain under planning.
“If not for all this trash, the water from the rain would flow properly and would not cause as much flooding, which affects residents in the barangay,” he said. / CAV WITH ZENN DEE TEJERO, CNU INTERN AND TRIXCY SHIEN COBARDE, BENEDICTO COLLEGE INTERN