Date of Award


Degree Name

Master of City and Regional Planning


City and Regional Planning


W. David Conn


This report focuses on using the Papathoma Tsunami Vulnerability Assessment Model (PTVA) to demonstrate the vulnerability of Cayucos to a 500-year tsunami, and using the results to inform specific planning recommendations. By modeling inundation with GIS and analyzing building attributes via the PTVA model, this study has gone beyond any previous vulnerability assessments of Cayucos. Findings include: delineation of the most vulnerable areas, estimates of numbers of lost civic buildings, commercial buildings and houses, as well as estimates of people displaced from tsunami damaged homes. The report goes on to discuss what mitigation measures are in place and what further specific steps could be taken to ensure the long term sustainability of the town and help reduce future tsunami losses.

Cayucos is a small coastal town in San Luis Obispo County, California; popular with tourists and locals for its beach, pier, and downtown. Intense coastal development and low lying topography makes Cayucos among the most tsunami vulnerable communities in the county. Many civic and economically important buildings, as well as homes, are within the 500-year tsunami inundation area.

In the absence of fully developed, and accessible assessment tools like FEMA’s HAZUS tsunami program; local planners have had only basic information to assess the community’s tsunami vulnerability. The Papathoma Tsunami Vulnerability Assessment Model (PTVA) is a method that uses available tsunami runup estimations and field data collection to produce a detailed assessment of individual building survivability and overall community vulnerability.