Building Damage in Manhattan
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BUILDING DAMAGE IN MANHATTAN N NO DAMAGE The most vulnerable district in S SLIGHT DAMAGE Minor cracks Manhattan would not be the one M MODERATE DAMAGE Larger cracks and some connection failures. closest to the epicenter, but rather E EXTENSIVE DAMAGE Although people may escape safely, the building the Upper East Side, due to vulner- will eventually have to be demolished. Significant able unreinforced masonry buildings cracks and connection failures. C COMPLETE DAMAGE M7 on soft soils. Structure is collapsed or in imminent danger of collapse. Extensive member and connection failures and major foundation cracking. HAZUS subdivides building damage into five Washington Heights 1 categories: 916 Inwood 543 493 No Damage (N on the figures to the right) Morningside Heights 140 30 Slight Damage (S) Hamilton Heights N S M E C Manhattanville 671 506 524 Moderate Damage (M) 148 32 Extensive Damage (E) N S M E C Complete Damage (C) Central Harlem 760 863 Manhattan Most at Risk Polo Grounds 685 307 The figure on this page shows the distribution 85 1153 of damage likely in 12 Manhattan neighborhoods Lincoln Square 1047 1223 Upper West Side N S M E C for an earthquake with Magnitude 7.0 intensity, Manhattan Valley 373 centered at the 1884 historic site. The results indi- 77 cate that an earthquake of this magnitude and loca- N S M E C East Harlem tion would result in the collapse or in the imminent 547 578 danger of collapse of 1,667 buildings in Manhattan 521 252 71 (the sum of all bars marked C, on the figures to the Flatiron N S M E C Midtown 1174 right). In this scenario, due to particularly soft soil 782 555 481 conditions on the Upper East Side, this location 136 would experience a PGA of 0.49, almost double the N S M E C 1542 Upper East Side PGA that the Financial District would experience, 1434 1308 Yorkville despite being located further from the epicenter. Chelsea 393 Carnegie Hill 76 Lenox Hill As this area also has a high percentage of unre- Clinton 1177 669 790 N S M E C 492 inforced buildings, it is particularly vulnerable to 151 earthquakes. N S M E C Reasons for Vulnerability Gramercy Soho 1221 As you can see from the figure to the right, the Greenwich Village 775 Murray Hill 584 Chinatown 517 Turtle Bay Upper East Side has the most buildings (4,753, 143 Little Italy Tudor City about 13 percent) and the most unreinforced N S M E C Noho Financial District masonry buildings (1,434, also 13 percent). In 1737 1040 Tribeca 883 fact, these buildings account for 18 percent of the 491 406 Seaport total square footage in Manhattan and, therefore, Battery Park CIty N S M E C 1404 East Village are the most at risk, contributing to a large por- 667 301 824 Lower East Side 183 382 141 707 477 Tomkins Square tion of the total loss in a seismic event. Buildings 319 N S M E C in Chinatown are also at greater risk for complete N S M E C collapse as a result of the same two factors: softer 1 The version of HAZUS used in this study (HAZUS-SR2) derives the number of buildings in each of the five damage states from the damage state soils and the predominance of masonry buildings. distributions of the total square footage in a census tract. The number of buildings assigned to each category is based on average building square footage size. Consequently, the actual number of buildings assigned to each damage state may be over estimated. 28 | NY | NJ | CT EARTHQUAKE RISKS AND MITIGATION.