Assessing community-level flood risk at the micro-scale by owner/occupant type and first-floor height
• +2
• Ayat Al Assi,
• Rubayet Bin Mostafiz,
• Carol Friedland,
• Robert Rohli
Ayat Al Assi
Louisiana State University
Author Profile
Rubayet Bin Mostafiz
Louisiana State University

Corresponding Author:rbinmo1@lsu.edu

Author Profile
Carol Friedland
Louisiana State University Agricultural Center
Author Profile
Evaluating flood risk is an essential component of understanding and increasing community resilience. A robust approach for quantifying flood risk in terms of average annual loss (AAL) in dollars at the community level is needed to provide valuable information for stakeholder decision-making. This research develops a computational framework to evaluate AAL at the community level by owner/occupant type (i.e., homeowner, landlord, and tenant) for increasing first-floor heights. The AAL values are calculated here by numerically integrating loss-exceedance probability distributions to represent economic annual flood risk to the building, contents, and use. A case study for a census block in Jefferson Parish, Louisiana, reveals that homeowners bear a mean AAL of $4,390 at the 100-year flood elevation (E_100), compared with$2,960, and \$1,590 for landlords and tenants, respectively, because the homeowner incurs losses to building, contents, and use, rather than only two of the three, as for the landlord and tenant. The results of this case study show that increasing first-floor heights reduces AAL proportionately for each owner/occupant type, and that two feet of additional elevation above E_100 may provide the most economically advantageous benefit. The modeled results suggest that Hazus Multi-Hazard (Hazus-MH) output underestimates the AAL by 11% for building and 15% for contents. Application of this technique to the community level while partitioning the owner/occupant types will improve planning for improved resilience and assessment of impacts attributable to the costly flood hazard.