Assessing storm surge risk in the context of urban informal settlements : A case of Navotas City, Metro Manila, The Philippines. | |
| Author | Morin, Veronique Marie |
| Call Number | AIT Diss. no.DM-14-07 |
| Subject(s) | Storm Surges Storm Surges--Philippines Disaster relief Risk management |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Disaster Preparedness, Mitigation and Management, |
| Publisher | Asian Institute of Technology |
| Series Statement | School of Environment, Resources and Technology |
| Abstract | Approximately one third of Metro Manila's 11.5 million residents live in informal communities. Coupled with high population densities, inadequate housing and infrastructure, and insecure residential status, a large proportion of the informal settlements in the region are situated in ha zard prone areas along waterways and the coast. Since the Philippines is one of the most tropical cyclone exposed countries in the world, informal settlers along Manila Bay are frequently affected by flooding from high tides and storm surges. In 2011, Typhoon Pedring generated one of the largest storm surges on record in Manila Bay and devastated the informal coastal communities, many of which were forcefully evicted after the di saster. The objective of this thesis is to use the case study of Typhoon Pedring to examine the storm surge risk to informal settlers, such that more effective risk reduction strategies can be devised for this rapidly growing population group. Research methods from both physical (natural sciences/ engineering) and human geography (social sciences) were applied to provide a more holistic understanding of disaster risk. For the hazard assessment, numerical simulations and a historical analysis of more than 50 years of recorded data were completed. To examine the vulnerability and capacity of informal settlers at the household level, mixed qualitative/quantitative methods were used. The analysis was mostly based on primary data that included field observations, survey questionnaires (434) with typhoon-affected families, focus group discussions and key informant interviews. The results of the hazard assessment revealed that Manila Bay is affected by about 1.7 storm surges per year, and that th e existing cyclone warning system is inadequate to alert coastal populations to storm surge hazards. The cyclone warning system uses the predicted maximum sustained wind speed to measure storm intensity, and then associates more intense storms with more intense storm surges. While Typhoon Pedring was neither the most intense nor the storm passing closest to the site (Category 2 storm passing more than 200 km to the north), it generated one of the largest storm surges on record. The investigation revealed that strong southwest monsoon winds interacted with the typhoon, resulting in a highly asymmetric shape, and thereby increasing the wind field and storm surge in Manila Bay. As a result, both households and local city officials were grossly unprepared for the damaging event. For the informal settlers in the study area, it was found that their vulnerability is increased and their capacity to cope with flood hazards is limited by Jack of access to various physical, social, financial and human reso urces. It was further found that structural and institutional barriers prevent them from accessing many such assets and resources. For example, extensive (and costly) documentation is required for informal settlers to gain access to various socialized programs, such as housing and health, which often limits the most vulnerable (target population) from availing of these services. Their vulnerability is rooted in everyday ha za rdous conditions, and the mechanisms used to cope with extreme events are not extraordinary, but rather an extension of daily measures. Informal settlers rely heavily on social capital because it is one of the few resources that is not controlled or restricted to any great extent by the political and economic elite. Both human and environmental changes driven from the global (climate change impacts) and local (land subsidence, population increases) levels are likely to keep ipcreasing the risk of informal settlers in coastal zones. Thus, it is critical that community based approaches be integrated with top down strategies to promote opportunities and remove barriers to increase the access profiles of the urban poor. |
| Year | 2014 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. DM-14-07 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Development and Sustainability (DDS) |
| Academic Program/FoS | Disaster Preparedness, Mitigation and Management (DM) |
| Chairperson(s) | Pennung Warnitchai; |
| Examination Committee(s) | Ahmad, Mokbul Morshed ;Sutat Weesakul ; |
| Scholarship Donor(s) | Natural Science and Engineering Research Council of Canada (NSERC) ;Asian Institute of Technology Fellowship; |
| Degree | Dissertation (Ph.D.) - Asian Institute of Technology, 2014 |