Impacts of Hurricane Dorian on the Bahamas: field observations of hazard intensity and performance of the built environment

ABSTRACT

On September 1 2019, Hurricane Dorian made landfall in Elbow Cay in the Bahamas with sustained winds of 295 km/h and a central pressure of 910 mb, with subsequent landfalls in Marsh Harbour and Grand Bahama Island, where it stalled for two days. This paper presents field observations of Dorian’s coastal hazards and impacts on the built environment in these locales, collected by the Structural Extreme Events Reconnaissance (StEER) Network. Data were collected using a mixed methodological approach: (1) surveying high-water marks and inundation extent, including an approximately 8 m high water mark in Marsh Harbour, (2) conducting surface-level forensic assessments of damage to 358 structures, and (3) rapidly imaging 475 km of routes using street-level panoramas. Field observations are complemented by a debris field analysis using high-resolution satellite imagery. Observed performance reiterates the potential for well-confined, elevated construction to perform well under major hurricanes, but with the need to codify such practices through the addition of storm surge design provisions and an increase in the design wind speeds in the Bahamas Building Code. This study further demonstrates the value of robust reconnaissance infrastructure for capturing perishable data following hurricanes and making such data rapidly available using publicly accessible platforms.

KEYWORDS:

• Hurricane
• Dorian
• Bahamas
• storm surge
• wind
• damage assessment

Acknowledgments

This material is based upon work supported by the National Science Foundation (NSF) under Award No. CMMI 1841667. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. Data was in part collected using equipment provided by NSF as part of the RAPID Facility, a component of the Natural Hazards Engineering Research Infrastructure, under Award No. CMMI: 1611820. The authors thank the RAPID Facility’s Andrew Lyda for traveling with FAST-1 for data collection, as well as Catlin Bourassa and Jacqueline Peltier for their support during this challenging mission. The authors especially recognize Steve Pece and his associates for their active participation and outstanding logistical support in the FAST-1 deployment. The authors also appreciate the partnership with contractor Mike Vorce of Site 360 who collected panoramas as part of FAST-2, as well as Davon Edgecombe, Terran Brice, and Kevin Brown of Caribbean Coastal Services in Nassau who assisted with the FAST-2 assessments on Great Abaco Island. The authors also appreciate the support provided by Steven Soehlig of Anthony Travel, and all the individuals who provided critical transportation services over the mission. The authors further appreciate James Done from the University Corporation for Atmospheric Research (UCAR) for developing and sharing the Hurricane Dorian wind field referenced in the paper. Special thanks also to Spatial Networks and Fulcrum Community for providing the platform for structural assessments, as well as NHERI DesignSafe-CI for the services supporting mission coordination and data curation.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data Availability Statement

• Data is curated under project ID PRJ-2555 in DesignSafe: https://www.designsafe-ci.org/

• StEER’s Fulcrum Community page

• Mapillary website for street-level panoramas: Mapillary - Street-level imagery, powered by collaboration and computer vision

• Marsh Harbour and Treasure Cay StreetView Scans (September 24-25, 2019): http://streetview.rapidfacility.org/Projects/Bahamas-Fast-1/player/

• Marsh Harbour and Treasure Cay StreetView Scans hosted on Google: https://goo.gl/maps/yLrBt52uP2tjsqPs5

• Grand Bahama StreetView Scans (October 5-8, 2019): http://streetview.rapidfacility.org/Projects/Bahamas-Fast-2/player/

• Grand Bahama StreetView Scans hosted on Google: https://goo.gl/maps/vaqeunYGFSG1QdFy5

  • Specific sites:

    • Sweeting’s Cay

    • Golden Grove Road - washed away

    • Golden Grove Rd - ocean front

    • Neighborhood near Golden Grove

    • Grand Bahama University

    • Jack Hayward Bridge

Additional information

Funding

This work was supported by the Division of Civil, National Science Foundation, Mechanical and Manufacturing Innovation [1841667].