DREAM completes flood hazard maps for 13 river basins

The Flood Modeling Component (FMC) of the DREAM Program, which uses processed LiDAR data for flood modeling, has announced that as of February 17, 2014, it has accomplished accurate and highly-relevant flood hazard maps for 13 river basin areas.

These are:

Cagayan de Oro
Magasawang Tubig
Ilog Hilabangan
Buayan Malungon

Currently in progress are flood hazard maps for Tagum-Libuganon, Agusan, Panay and Agno. Most of the aforementioned river basins have hazard maps for the 100-year rainfall return and will just need more processing time for the other scenarios such as the 50-year, 25-year, 10-year, and 5-year rainfall return. These scenarios simply show the magnitude of flood hazards and its possibility of occurrence for a certain period of time.

For the early warning system, the DREAM FMC has a total of 11 HEC-HMS (watershed) models online. These include stations for Jalaur, CDO, Iponan, Mandulog, Panay, Ilog Hilabangan, Agno and Tagoloan. Meanwhile, HEC-HMS models for Iligan, Angat, Davao, Infanta, Pampanga, Agusan and Bicol have already been calibrated but issues arise from their respective sensors thus the team has postponed uploading these models online until the all the sensors have been checked for accuracy.

HEC-RAS (floodplain) models are also being done by the FMC. Currently online to serve as the real time inundation flood monitoring are models for CDO and Mandulog. In the queue for uploading are models for Tagoloan, Ilog Hilabangan and Iponan. Similar to some HEC-HMS models, other HEC-RAS models are available but cannot be uploaded online due to water level sensor issues for the areas of Angat, Davao, Iligan, and Agusan river basins.

To provide more information on the areas which would benefit from the flood models, the Bicol river goes through the provinces of Albay, Camarines Norte, Camarines Sur, and Quezon. Thus, Regions 5 and 4A (CALABARZON) are stakeholders and would have valuable uses for FMC’s flood hazard maps. The Cagayan de Oro river basin stretches out to the provinces of Bukidnon, Lanao del Norte, and Misamis Oriental, primarily Region 10 or Northern Mindanao. The Iligan river basin is found in Lanao del Norte, also in Region 10. The Pampanga river winds its way through a multititude of provinces, specifically Aurora, Bataan, Bulacan, Metro Manila, Nueva Ecija, Nueva Vizcaya, Pampanga, Pangasinan, Rizal, Tarlac, and Zambales, thus covering Region 3 (Central Luzon), National Capital Region, Region 2 (Cagayan Valley), Region 1 (Ilocos Region), and Region 4A (CALABARZON) as well. Lucena river basin is also present in Region 4A.

Jalaur river is located across the provinces of Antique, Capiz, and Iloilo—all in Region 6 (Western Visayas). Similarly, Ilog-Hilabangan is situated in Region 6 (Western Visayas) and Region 7 (Central Visayas), but this time in Negros Occidental and Negros Oriental. Davao river encompasses the provinces of Bukidnon, Davao del Norte, Davao del Sur, and North Cotabato, thus covering Regions 10, 11, and 12, which are Northern Mindanao, Davao Region, and SOCCSKARGEN, respectively. Magasawang-Tubig river basin in Oriental Mindoro under Region 4B (MIMAROPA). Tagoloan river passes through Bukidnon and Misamis Oriental as well, both in Region 10 (Northern Mindanao). Buayan-Malungun river basin is part of the provinces of the Davao del Sur, Sarangani, and South Cotabato. These provinces are in Regions 11 (Davao Region) and 12 (SOCCSKARGEN), respectively. Other river basins with flood hazard maps are the Mandulog and Iponan rivers, both spreading out into Lanao del Norte, Lanao del Sur, and Bukidnon—under Region 10 and ARMM, respectively. With the 100-year rainfall looming in the horizon, as evidenced by Typhoon Yolanda, all these critical river basins need to be managed by government agencies, LGUs, NGOs, and the private sector alike with the use of flood hazard maps.

What’s next for the FMC to model as part of the DREAM Program deliverables are the Agus, Cagayan, Infanta, and Mindanao river basins. Mindanao river is one of the major rivers affecting Regions 10, 11, 12, and ARMM by its sheer size. These river basins are targeted to be completed by 2014.