Science-based drainage plan

CEBU, Philippines — A science-based Drainage Master Plan is what the city council is asking Mayor Nestor Archival to create, urging him to confront the flooding crisis with a comprehensive solution rather than another study left on the shelf.

This call comes from a resolution filed by Councilor Harold Go and approved by the council, urging Archival to engage a qualified consultant, engineering firm, consortium, academic institution, or multidisciplinary technical team to prepare and update the plan.

It mandates that the work be undertaken using an integrated watershed-based and coastal-to-upland approach, beginning with coastal and low-lying barangays and their drainage outfalls, then progressively moving toward interconnected inland and upland catchment areas.

The scope of the plan requires a full inventory, survey, and mapping of existing drainage infrastructure, rivers, creeks, waterways, culverts, canals, and coastal outfalls.

It calls for the delineation and analysis of watersheds and drainage catchments, hydrologic and hydraulic modeling based on updated rainfall and land-use data, and the identification of flood-prone areas, bottlenecks, undersized facilities, and obstructions.

The plan is also expected to assess coastal outfalls and tidal influences, protect or rehabilitate natural waterways, and prioritize both structural and non-structural flood mitigation interventions.

Preliminary engineering concepts with indicative cost estimates, a phased implementation program, and objective criteria for prioritizing projects according to flood risk, population affected, connectivity, urgency, cost-effectiveness, and feasibility are also required.

Finally, the plan, as presented by Go, must identify at least one pilot barangay for initial implementation and establish measurable performance indicators to determine whether interventions reduce flood depth, duration, and impacts on households and critical facilities.

Go, an architect and chairman of the Committee on Urban Planning, said in a press conference that the city must first secure an accurate as-built plan of its drainage system.

“Importante kayo sa tanan, ang himuon sa city nato is mukuha gyud ta ug third party or if kaya sa atong kaugalingon nga departments, silay muhimo ug as-built plan sa tanang drainage system sa Cebu City. So e-mapping na nila tanan, ang kanang mga kanal, unsa kadako, asa niagi,” he explained.

He added that only by knowing the system’s true capacity can the city identify bottlenecks and hotspots before introducing pilot projects.

This year alone, floods have repeatedly submerged Cebu’s communities. On July 30, waters rose three to six feet in Sitio Tambisan, Barangay Tisa, displacing families and forcing residents to wade through waist-deep streets.

Similar inundations hit several other barangays, stressing the limits of the existing drainage system.

“Kon igo ra na siya, unya mapun-an kay nay uwan, mu overflow gyud. So that is the first thing nga kinahanglan himuon,” Go said, pointing out that current capacity is already strained by daily water use even before heavy rains.

Archival has launched declogging drives, the latest of which was conducted in the Suba-Pasil area.

He also revived the three-meter easement campaign along rivers and announced plans for a stormwater reservoir in Tisa-Labangon.

He has also directed engineers to revisit past drainage studies and coordinate with the Department of Public Works and Highways.

But Go insists these efforts must be tied together under a master plan.

“Hopefully ma review ni sa mga consultant ni Mayor, makakuha ta ug sakto nga third party nga makakuha gyud sa accurate nga asbuilt plan sa atong drainage system sa Cebu City,” he said.

Go also warned that garbage disposal and enforcement must be part of the solution.

“Kana siyang dapita, kinahanglan na siyag strong enforcement ug disiplina sa mga tawo. Interconnected gyud tanan,” he noted, adding that clogged waterways caused by waste dumping worsen flooding.

“Daghan kaayog tan-awunon. For all we know, naa na nay pundasyon o haligi nga nibabag sa mga drainage. Mao na siya nga kinahanglan gyud nato ug long-term solution,” he added. (CEBU NEWS)