CoreLogic: 6.8M Homes at Risk for Hurricane-Related Storm Surge Damage

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More than 6.8 million homes located on the Atlantic and Gulf coasts are in danger of hurricane storm surge damage, according CoreLogic’s latest storm surge report.

The total cost for reconstruction of the homes located in 19 states and the District of Columbia is more than $1.5 trillion.

The property information and analytics provider’s 2016 Storm Surge Report release coincides with the June 1 start of the Atlantic hurricane season. Using more advanced and granular data than in previous years, the 2016 analysis shows an increase from 2015 in the overall number of homes at risk of storm surge as well as an increase in the reconstruction value of these homes. Despite the overall increases, the 2016 analysis shows a decrease in the most extreme category for both the number and value of homes at risk.

Table 1 – Total Number of Homes at Risk Nationally and Estimated Reconstruction Cost Value

Storm Surge Risk Level (Storm Category)	Total Homes Potentially Affected	Total Estimated RCV (U.S. Dollars)
Extreme (Category 1-5 storm)	813,587	$191,973,679,305
Very High (Category 2-5 storm)	1,658,151	$398,669,536,279
High (Category 3-5 storm)	2,006,258	$455,622,094,460
Moderate (Category 4-5 storm)	1,471,389	$332,852,780,000
Low (Category 5 storm)	880,799	$166,974,115,052
Total	6,830,184	$1,546,092,205,096

“Using more granular-level data has given us an even clearer picture of which homes are at risk of storm surge damage,” said Dr. Tom Jeffery, senior hazard risk scientist for CoreLogic. “Despite the overall increases in risk, we were glad to see that the number and value of homes in the most extreme, and dangerous, category actually declined. It just goes to show the power of how advanced data can improve risk assessment at the property level.”

At the regional level, the Atlantic Coast has just under 3.9 million homes at risk of storm surge with an RCV of $953 billion, and the Gulf Coast has just over 2.9 million homes at risk with $592 billion in potential exposure to total destruction damage (Table 2).

Table 2 – Residential Exposure by Coastal Region

Regional Risk	Atlantic Coast Homes	Atlantic Coast RCV (U.S. Dollars)	Gulf Coast Homes	Gulf Coast RCV (U.S. Dollars)
Extreme	449,466	$118,228,887,418	364,121	$73,744,791,887
Very High	965,063	$260,930,498,221	693,088	$137,739,038,058
High	1,058,829	$257,010,009,560	947,429	$198,612,084,900
Moderate	945,587	$229,021,402,222	525,802	$103,831,377,778
Low	459,099	$88,344,523,473	421,700	$78,629,591,579
Total	3,878,044	$953,535,320,894	2,952,140	$592,556,884,202

At the state level, Texas and Florida, which have the longest coastal areas, consistently have more homes at risk than other states. Florida ranks first with 2.7 million at-risk homes across the five risk categories and Texas ranks third with 531,169 at-risk homes (Table 3). Since the number of homes at risk strongly correlates with the accompanying RCV, these two states rank first and fifth, respectively for having the largest RCV (Table 4). States with less coastal exposure but lower-lying elevations that extend farther inland, such as Louisiana (ranked second at 800,521 at-risk homes) and New Jersey (ranked fourth at 468,823 at-risk homes), tend to have more total homes at risk because of the potential for surge water to travel farther inland. Louisiana and New Jersey are also near the top of the list for RCV, with Louisiana totaling $184 billion (ranked second) and New Jersey totaling $139 billion (ranked fourth).

Table 3 – State at-Risk Totals (Ranked by the Number of Homes at Risk)

Rank	State	Extreme	Very High	High	Moderate	Low*	Total
1	Florida	343,089	701,739	674,817	532,217	479,764	2,731,626
2	Louisiana	91,385	121,573	399,898	118,019	69,646	800,521
3	Texas	40,277	75,021	132,507	127,393	155,971	531,169
4	New Jersey	94,643	180,269	104,010	89,901	N/A	468,823
5	New York	74,654	147,129	122,044	114,903	N/A	458,730
6	Virginia	26,081	65,946	150,883	118,253	42,450	403,613
7	South Carolina	35,514	88,485	81,039	82,177	51,425	338,640
8	North Carolina	30,785	58,829	62,456	46,086	46,556	244,712
9	Massachusetts	10,762	36,412	57,243	56,977	N/A	161,394
10	Georgia	9,290	41,003	53,398	34,272	10,755	148,718
11	Maryland	18,809	43,495	39,563	29,005	N/A	130,872
12	Mississippi	9,254	20,795	29,715	28,962	11,440	100,166
13	Pennsylvania	852	19,843	36,071	26,485	N/A	83,251
14	Connecticut	6,997	21,634	17,955	21,016	N/A	67,602
15	Delaware	8,686	14,859	14,560	16,049	N/A	54,154
16	Alabama	4,880	8,171	13,993	11,129	12,792	50,965
17	Rhode Island	1,869	6,182	9,138	9,404	N/A	26,593
18	Maine	5,484	2,683	4,036	6,148	N/A	18,351
19	New Hampshire	276	4,083	2,924	2,233	N/A	9,516
20	District of Columbia	N/A**	N/A**	8	760	N/A	768
Total	813,587	1,658,151	2,006,258	1,471,389	880,799	6,830,184

*The “Low” risk category is based on Category 5 hurricanes which are not likely along the northeastern Atlantic Coast. States in that area have N/A designated for the Low category due to the extremely low probability of a Category 5 storm affecting that area.

** Washington, D.C. has no Atlantic coastal homes, but can be affected by larger hurricanes that push storm surge into the Potomac River. Category 1 and 2 storms will likely not generate sufficient storm surge to affect homes in Washington, D.C.

Table 4 – Reconstruction Cost Value of Homes at Risk by State

Rank	State	Extreme	Very High	High	Moderate	Low*	Total
1	Florida	$70,047,668,435	$144,324,089,970	$133,941,137,129	$99,021,281,198	$88,332,267,100	$535,666,443,832
2	Louisiana	$19,261,303,207	$26,484,796,128	$94,037,897,235	$27,372,451,734	$17,186,539,031	$184,342,987,335
3	New York	$27,192,190,159	$59,542,751,090	$46,345,353,434	$43,938,734,695	N/A	$177,019,029,378
4	New Jersey	$26,447,682,381	$53,059,619,267	$31,790,469,470	$28,301,355,113	N/A	$139,599,126,231
5	Texas	$5,835,289,703	$11,550,329,115	$23,317,525,550	$24,438,975,019	$26,505,485,218	$91,647,604,605
6	Virginia	$6,558,725,763	$15,489,587,692	$31,072,040,615	$24,525,113,051	$9,708,289,679	$87,353,756,800
7	South Carolina	$10,119,452,942	$22,371,712,736	$17,892,600,081	$17,224,909,503	$10,050,257,900	$77,658,933,162
8	Massachusetts	$3,192,412,745	$10,867,434,276	$17,351,600,509	$18,135,938,844	N/A	$49,547,386,374
9	North Carolina	$5,866,070,772	$11,772,926,993	$12,629,945,559	$9,452,537,798	$9,272,277,927	$48,993,759,049
10	Georgia	$2,823,103,183	$10,173,092,963	$10,750,858,962	$6,419,508,663	$1,885,691,326	$32,052,255,097
11	Maryland	$4,533,798,320	$10,363,999,665	$9,197,276,146	$7,045,549,151	N/A	$31,140,623,282
12	Connecticut	$2,470,802,868	$7,222,627,340	$5,956,081,705	$6,841,880,454	N/A	$22,491,392,367
13	Mississippi	$1,962,934,062	$3,971,758,807	$5,408,276,830	$5,182,968,425	$1,998,298,521	$18,524,236,645
14	Delaware	$2,592,865,851	$4,136,821,593	$4,238,888,654	$4,465,099,655	N/A	$15,433,675,753
15	Pennsylvania	$205,882,424	$2,509,057,342	$4,742,484,301	$3,554,045,351	N/A	$11,011,469,418
16	Alabama	$951,444,860	$1,419,732,376	$2,366,412,240	$1,964,047,014	$2,035,008,350	$8,736,644,840
17	Rhode Island	$534,329,842	$1,830,867,728	$2,674,150,401	$2,673,066,234	N/A	$7,712,414,205
18	Maine	$1,316,675,180	$687,634,190	$1,058,854,921	$1,589,131,085	N/A	$4,652,295,376
19	New Hampshire	$61,046,608	$890,697,008	$846,888,075	$593,570,376	N/A	$2,392,202,067
20	District of Columbia	N/A**	N/A**	$3,352,643	$112,616,637	N/A	$115,969,280
Total	$191,973,679,305	$398,669,536,279	$455,622,094,460	$332,852,780,000	$166,974,115,052	$1,546,092,205,096

At the local level, 15 Core Based Statistical Areas (CBSAs) account for 67.3 percent of the 6.8 million total at-risk homes and 68.3 percent of the total $1.54 trillion RCV (Table 5). This disproportionate distribution of homes suggests that the location of hurricanes that hit land is often a more important factor than the number of storms that may occur during the year. The Miami CBSA, which includes Fort Lauderdale and West Palm Beach, has the most homes at risk totaling 780,482 with an RCV of just under $144 billion. By comparison, the New York City CBSA has slightly fewer homes at risk at 719,373, but a significantly higher total RCV totaling $260 billion.

Table 5 – Storm Surge Risk for Top 15 Metropolitan Areas

Rank	Metropolitan Area	Total Homes Potentially Affected By All Categories of Hurricane	Total Estimated RCV (U.S. Dollars)
1	Miami, FL	780,482	$143,949,383,422
2	New York, NY	719,373	$260,195,234,842
3	Tampa, FL	454,746	$80,627,283,072
4	New Orleans, LA	390,806	$94,043,948,226
5	Virginia Beach, VA-NC	385,084	$83,472,805,334
6	Cape Coral, FL	306,953	$61,989,183,591
7	Houston, TX	280,112	$51,868,761,737
8	Bradenton, FL	250,615	$47,331,097,845
9	Naples, FL	180,919	$43,178,509,775
10	Jacksonville, FL	166,709	$35,807,031,655
11	Philadelphia, PA	165,940	$31,884,862,628
12	Charleston, SC	145,356	$36,193,547,227
13	Boston, MA	129,167	$38,480,093,842
14	Myrtle Beach, NC	123,645	$21,588,181,602
15	Lafayette, LA	119,942	$25,831,094,601
Total	4,599,849	$1,056,441,019,399

To illustrate varying degrees of flood risk exposure, the analysis compares homes that are not located within FEMA 100-year floodplains against the number of homes located in surge inundation zones, as well as those located in both surge and FEMA Special Flood Hazard Areas (SFHA). This data can be found in the full report at:

http://www.corelogic.com/landing-pages/2016-corelogic-storm-surge-risk-report.aspx?WT.mc_id=prnw_160526_uk8kN

All charts produced by CoreLogic

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