Flood Hazard GIS Files of portions of Loreto, Province of Dinagat Islands

The dataset consists of zipped GIS Shapefiles of numerical model simulated flood extents and hazard levels for portions of Loreto, Province of Dinagat Islands, under various rainfall scenarios. Each scenario has a corresponding probability of occurrence in any given year based on Rainfall-Intensity Duration Frequency (RIDF) curves generated by PAGASA for its Surigao City Station (the nearest to this municipality).

The GIS files were generated through flood modeling by the Phil-LiDAR 1.B.14 Project of Caraga State University using LiDAR-derived geospatial datasets, particularly Digital Terrain Model (DTM) as main source of topographic information. HEC HMS and HEC RAS 2D were utilized in the flood modeling and simulation.

To learn more about how the flood hazard GIS files were generated, please refer to the CSU Phil-LiDAR 1.B.14 Project Terminal Report at https://drive.google.com/file/d/1unJYxltWPWZe7kWyYTLYhsD0FBDR30wV/view?usp=sharing

The RIDF-based rainfall scenario-based flood hazard maps (FHM) are described as follows:

*2-year Rain Return Period GIS Files

This GIS file depicts the numerical model simulated flood extent and hazard levels that may be experienced if the rain falling in the watersheds within and upstream of the municipality reaches 188.70 mm in 24 hours. This rainfall scenario has 50% probability of occurrence in any given year.

*5-year Rain Return Period GIS Files

This GIS file depicts the numerical model simulated flood extent and hazard levels that may be experienced if the rain falling in the watersheds within and upstream of the municipality reaches 386.50 mm in 24 hours. This rainfall scenario has 20% probability of occurrence in any given year.

*10-year Rain Return Period GIS Files

This GIS file depicts the numerical model simulated flood extent and hazard levels that may be experienced if the rain falling in the watersheds within and upstream of the municipality 351.20 mm in 24 hours. This rainfall scenario has 10% probability of occurrence in any given year.

*25-year Rain Return Period GIS Files

This GIS file depicts the numerical model simulated flood extent and hazard levels that may be experienced if the rain falling in the watersheds within and upstream of the municipality reaches 433.00 in 24 hours. This rainfall scenario has 4% probability of occurrence in any given year.

*50-year Rain Return Period GIS Files

This GIS file depicts the numerical model simulated flood extent and hazard levels that may be experienced if the rain falling in the watersheds within and upstream of the municipality reaches 493.70 mm in 24 hours. This rainfall scenario has 2% probability of occurrence in any given year.

*100-year Rain Return Period GIS Files

This GIS file depicts the numerical model simulated flood extent and hazard levels that may be experienced if the rain falling in the watersheds within and upstream of the municipality reaches 553.90 mm in 24 hours. This rainfall scenario has 1% probability of occurrence in any given year.

The flood hazards are categorized into three (3):

  • Low Hazard: 0.1 m - 0.5 m flood depth

  • Medium Hazard: 0.5 m - 1.5 m flood depth

  • High Hazard: greater than 1.5 m flood depth

The dataset's terms of use are governed by the Geo-SAFER Mindanao Program EULA available at https://drive.google.com/file/d/1jhPTezK6vUE0UaqCgYK8V3Y2UPwoeaLC/view?usp=sharing

Data and Resources

Additional Info

Field Value
Source
Version
Author Phil-LiDAR 1.B.14 Project, Caraga State University
Author Email Phil-LiDAR 1.B.14 Project, Caraga State University
Maintainer Caraga Center for Geo-Informatics (CCGeo), Caraga State University, Philippines
Maintainer Email Caraga Center for Geo-Informatics (CCGeo), Caraga State University, Philippines