Superstorm Sandy Willis Re s post-event field damage survey preliminary report

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1 HURRICANE DAMAGE SURVEY REPORT event November 8, 2012 Superstorm Sandy Willis Re s post-event field damage survey preliminary report Immediately after Sandy s landfall, representatives of Willis Re s Catastrophe Management Services team spent four days in the field assessing the damage caused by Superstorm Sandy. This report summarizes the initial observations from this damage survey. Executive Summary Sandy made landfall on Monday night around 8 pm EDT, October 29, near Atlantic City, NJ with estimated maximum sustained winds at 80 mph. Sandy was an extraordinary storm because of its large windfield. In addition, it became complex when interacting with another weather system to the west, creating a large superstorm. The high spring tide (when the sun, moon and earth are in alignment, causing the tide range to be at maximum) at the time of Sandy worsened the storm surge impact on the East Coast. Immediately after Sandy s landfall, representatives of Willis Re s Catastrophe Management Services team spent four days in the field assessing the damage caused by Sandy. The objective of Willis Re s damage survey was to research and to collect examples of property damage due to wind and surge. Despite the various challenges accessing these damaged areas we were able to survey various properties exposed to the storm in Ocean City, Atlantic City, Spring Lake, Belmar and Avon-by-the-Sea in New Jersey and Staten Island, Coney Island and Rockaway Beach in New York. We observed many examples of significant structural damage to buildings from the storm surge and related flooding. Storm surge damage to buildings ranges from moderate to complete collapse. Damage to boats and automobiles due to storm surge was widespread and extensive. In general, the direct damage to properties due to the wind component of the storm was none to minor in the surveyed areas. However, in a few highly localized areas, minor to moderate wind damage was observed. In addition, damage to buildings from tree fall was widely observed in all areas. Copyright 2012 Willis Limited / Willis Re Inc. All rights reserved: No part of this publication may be reproduced, disseminated, distributed, stored in a retrieval system, transmitted or otherwise transferred in any form or by any means, whether electronic, mechanical, photocopying, recording, or otherwise, without the permission of Willis Limited / Willis Re Inc. Some information contained in this document may be compiled from third party sources and we do not guarantee and are not responsible for the accuracy of such. This document is for general guidance only and is not intended to be relied upon. Any action based on or in connection with anything contained herein should be taken only after obtaining specific advice from independent professional advisors of your choice. The views expressed in this document are not necessarily those of Willis Limited / Willis Re Inc., its parent companies, sister companies, subsidiaries or affiliates (hereinafter Willis ). Willis is not responsible for the accuracy or completeness of the contents herein and expressly disclaims any responsibility or liability for the reader's application of any of the contents herein to any analysis or other matter, or for any results or conclusions based upon, arising from or in connection with the contents herein, nor do the contents herein guarantee, and should not be construed to guarantee, any particular result or outcome. Willis accepts no responsibility for the content or quality of any third party websites to which we refer.

2 Damage from Storm Surge Extensive storm surge damage to buildings and contents was observed in all cases. Flood depths, as indicated by watermarks up to four feet above the first floor was observed in almost all properties located less than 0.2 miles from the coast. Watermarks on properties as far as 0.3 miles from the coast indicated storm surge of five to six feet. Storm surge height up to 7.5 feet was also observed along the coast of Rockaway Beach and Coney Islands. Picture 1 and Picture 2 at right respectively show the flood depth above the first occupied floor and the storm surge height watermarks measured outside a residential building located 0.14 miles away from Avon-by-the-Sea, NJ s coast. A massive amount of sand was moved on shore by the storm surge, indicating huge amounts of wave energy generated by Superstorm Sandy. We observed ocean sand up to two feet on many streets and inside many properties located as far as 0.15 to 0.25 miles from the coast. Picture 1 Picture 2 Picture 3 and Picture 4 respectively show sand deposits inside a beach front house in Ocean City and piles of sand from shoveling part of a street in Rockaway Beach. Picture 3 Picture 4 Extensive damage to boats and automobiles was observed in all surveyed areas. Cars parked along the streets were piled up and pushed away from their parked locations due to the high velocity storm surge. In addition, many boats were pushed on to the streets by the storm surge and smashed into neighboring buildings, causing additional structural damage. Pictures 5 and Picture 6 respectively show damage to boats and automobiles. Page 2 of 5

3 Picture 5 Picture 6 Damage to contents was widespread and extensive. In some cases, total loss of contents was observed due to high storm surge and related flood levels. In areas like the neighborhood of Lake Como in Belmar, some buildings are still under water. Storm surge brought a large volume of ocean water into the lake, resulting in rising water levels and flooding on all properties surrounding this lake up to 1000 feet in distance. Total loss to these properties can be expected as water is receding very slowly. We observed two to four feet of flood water in the crawl spaces of many properties in the surveyed areas. Structural damage due to flooded crawl spaces and foundations should be expected in the future for many of these properties. We noticed that structures elevated and on stilts experienced relative less damage compared to other structures. We also observed in a few areas that sea walls and sand dunes along the coast helped to reduce storm surge impact on waterfront structures to some extent. However, in many cases, storm surge was able to overtop these sea walls. Picture 7 and Picture 8 respectively show piles of damaged contents on a street and properties that are still under water around Lake Como in Belmar, NJ. Picture 7 Picture 8 Damage from Wind Overall, none to minor damage to buildings from direct winds of Sandy was observed. However, damage to roofing and wall siding was observed in a few localized areas. We recommend further investigation of Sandy s complex windfield to help determine the reasons for the spotty wind damage patterns observed on the ground. Page 3 of 5

4 We noted that the majority of buildings damaged due to wind represented older construction. Overall the newer construction performed well and any damage to the newer construction could be attributed to poor workmanship. Wind damage to a few small commercial oceanfront structures was also observed in Spring Lake, NJ. Picture 9 and Picture 10 respectively show wind damage to vinyl siding of a residential building and to a low-rise waterfront commercial building in Spring Lake, NJ. Picture 9 Picture 10 Extensive tree damage was observed in all areas due to strong winds. In some areas of New Jersey and New York every other house had a tree fall. It was also observed that tree fall caused extensive damage to parked vehicles, car ports / garages, building envelope and electrical power lines. Picture 11 and Picture 12 respectively shows roofing damage to an old small commercial building and to a mid-rise commercial multifamily dwelling. Picture 11 Picture 12 Page 4 of 5

5 Conclusions We observed many examples of extensive structural damage to buildings from storm surge and the related flooding in the surveyed areas. Building damage due to storm surge ranged from moderate to complete collapse. Storm surge damage to boats and automobiles was extensive and widespread. In general, the direct damage to buildings due to the wind component of the storm was none to minor in the surveyed areas. We did observe, though, significant and widespread damage to buildings due to tree fall. Willis Re s Catastrophe Management Services team hopes to perform another damage survey to cover more severely damaged areas, like Hoboken (NJ), Long Island Beach (NY) and downtown Manhattan, once these areas became accessible to the general public. In the coming weeks we will evaluate all the scientific data, observations from our field surveys and other information available for this event. We are confident that the results of this detailed study in conjunction with insurers actual experience from Superstorm Sandy will be useful for companies to make business decisions in the future. Contact us Prasad Gunturi 7760 France Avenue South Minneapolis, MN prasad.gunturi@willis.com The contents herein are provided for informational purposes only and do not constitute and should not be construed as professional advice. Any and all examples used herein are for illustrative purposes only, are purely hypothetical in nature, and offered merely to describe concepts or ideas. They are not offered as solutions to produce specific results and are not to be relied upon. The reader is cautioned to consult independent professional advisors of his/her choice and formulate independent conclusions and opinions regarding the subject matter discussed herein. Willis is not responsible for the accuracy or completeness of the contents herein and expressly disclaims any responsibility or liability for the reader's application of any of the contents herein to any analysis or other matter, nor do the contents herein guarantee, and should not be construed to guarantee, any particular result or outcome. Page 5 of 5