Quantifying resilience to flooding among households and local government units using system dynamics : the case of metro manila

System dynamics is a flexible approach for modeling stocks, flows and feedbacks within a system and for tracing behaviors through time. In the context of flood resilience modeling, it can be used to track the loss of system performance due to adverse impacts of flooding at the onset of extreme rainfall, as well as the potential recovery of the system in time due to adaptive measures. A generic system dynamics model for resilience developed by Simonovic and Peck (2013) is adapted to analyze flooding impacts in Metro Manila cities for the socio-economic and organizational sectors. For the socioeconomic sector, monetized household assets were selected as the key stock, with the expenditures and damages due to flooding as outflows from the stock, and income and relief/donations as inflows. Complementing this, the organizational sector model mainly tracks the Local Government Unit (LGU) monetized assets and resources. Similarly, damages due to flooding and spending for relief and recovery decrease the stock of resources while inflows from local and external sources (e.g. funds from the national budget or foreign aid) increase the stock. The household and LGU models are tested and used to evaluate potential adaptation scenarios that seek to make resources available for households and LGUs to build resilience.