Tecnología y ciencias del agua (Aug 2011)
Most probable cost of flood damage in residential areas in Mexico.
Abstract
Stage-damage curves for calculating flood loss based on the maximum water height reached allow for the economic assessment of damages generated by floods in river basins. This is one of the most commonly used direct evaluation methods. This work presents a proposal for an innovative method to define these curves, based on the beta distribution function as a probabilistic model. The curves obtained were used to quantify tangible direct damage in residential zones in Mexico. The residential areas were classified based on the urban marginalization index (MI) for the Basic Geo-Statistical Area (BGSA), obtaining five BGSA categories (very high MI, high MI, average MI, low MI and very low MI). The type and quantity of goods was then identified for each BGSA category, as well as their economic value, and the percentage of affectation of these goods was determined according to the highest level that the water could reach inside a home. The minimum, maximum and most probable stage-damages curves were then determined for each BGSA category and a mathematical regression model was obtained in order to calculate the economic damage corresponding to each water level. The use of this new method will provide an estimate of the magnitude of flood affectation in residential zones in Mexico, which would improve the evaluation of relevant measures to prevent, mitigate or reduce the direct cost of floods.