This technical report provides information on the social and economic valuation of the flood protection benefits from mangroves in the Philippines. This work aims to support decisions across development, aid, risk reduction and conservation sectors as they seek to identify sustainable and cost-effective approaches for risk reduction.
The research applied the Expected Damage Function approach recommended by the World Bank to quantify the risk reduction benefits from mangroves in the Philippines. Using high-resolution flooding models, the researchers examined the flooding that would occur with and without mangroves under different storm conditions throughout the Philippines, and estimates the annual expected benefits of mangroves for protecting people and property in social and economic terms. The brief provides information on flooding under regular storms and under extreme conditions (e.g. typhoon) and compares the people and property damaged under 3 different scenarios of mangrove cover: historical mangrove cover (1950), current mangrove cover (2010), and no mangrove cover. The protection services of mangroves are valued nationally across the Philippines using national models. The values obtained from these national models are compared to values from sensitivity analyses in a few locations (i.e., Pagbilao and Busuanga) calculated with very high-resolution data and models, so that the results of the national models may be verified.