Rain Falls Too Much: Assessing Flood Risk Through Simple Exposure-Based Approach
Keywords:
Rainfall intensity, Flood levels, Simple exposure computation, Urban flood vulnerability, Cebu CityAbstract
In this study, the relationship between rainfall intensity and flood levels in Cebu City, Philippines, was examined using a simple exposure computation method. The study involved analyzing the rainfall (mm) and accompanying flood levels (cm) for the year 2025 using simple arithmetic procedures such as the mean, difference, and rate of increase. The results indicated a distinct pattern between the rainfall and flood levels, characterized by lower rainfall and steady levels (5 cm) from January to April and evidently higher rainfall and levels during the wet months from June to October. The mean annual rainfall was determined to be 132.08 mm, and the average flood levels reached were 12.75 cm. The difference computation indicated regular increments in the levels by 5 cm from April to July, indicating the start and intensification of floods during the wet months, followed by irregularicreases near the end of the year. Finally, the rate of increase computation portrayed increasing vulnerability to floods for a whole year with a peak in October at 0.12cm/mm precipitation, signifying a lower efficiency and higher degrees of saturation during peak precipitation months. In conclusion, this study verifies a direct relationship between rainfall and levels and validates the capability and usability of simple computational mathematics to accurately examine and infer floods and aid in risk preparations and studies at the school and LGU levels.
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Copyright (c) 2026 Marla Charmaine Z. Mindoro, Lindsay G. Vallega, Jacob T. Lazarra (Author)
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