1. RiskMeter Lessons from
Hurricane Sandy
©Copyright 2012, CDS Business Mapping, LLC. All Rights Reserved.

2. Agenda
 Overview of Surge Modeling
 Difference Between Flood and Surge
Maps
 Sizing the Problem
 Examples from Sandy

3. Introduction
 Insurance companies, particularly commercial
insurers, are concerned with coastal flooding
 Hurricane Sandy caused significant losses from
surge
 Hurricane Sandy was more of a flood event than
a wind event
 Recent court rulings have held insurers liable for
hurricane flooding even if not technically
covered

4. About CDS Storm Surge Model
Model is based upon two different sources
 SLOSH Model
 Most well known storm surge model
 Elevation Data
 Using 30m digital elevation models

5. What is SLOSH Data?
 Slosh predicts storm surge levels based
upon different hurricane categories
 The data we use predicts storm surge
heights at high tide
 worst case scenario
 The heights shown are the surge heights
above sea-level, not above the ground

6. Texas SLOSH Basins
Overlapping basins

7. Slosh Basins-Long Island 7.3,11.2,15.1,18
7.3,11.2,15.1,18
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9 6.5,9.8,13.2,16.5
6.5,9.8,13.2,16.5
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9 7,10.8,14.3,17.9
7,10.8,14.3,17.9
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9 99.9,99.9,99.9,16.6
99.9,99.9,99.9,16.6
7.1,10.3,13.8,17.2 6.1,9,12,15.1
6.1,9,12,15.1 6.5,9.8,13.2,16.5
6.5,9.8,13.2,16.5
7.1,10.3,13.8,17.2
7.9,11.5,15.4,18.9
7.9,11.5,15.4,18.9
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9 6.6,9.5,12.5,15.7
6.6,9.5,12.5,15.7 6.8,10.2,13.6,16.9
6.8,10.2,13.6,16.9
6.2,9.3,12.4,15.5
6.2,9.3,12.4,15.5
7.9,11.3,15,18.6
7.9,11.3,15,18.6
The label show8.4,12.2,16.1,20
8.4,12.2,16.1,20 7.3,10.6,14,17.3
7.3,10.6,14,17.3 6.3,9,11.8,15
6.3,9,11.8,15 6.5,9.7,12.9,16.1
6.5,9.7,12.9,16.1
surge heights for 8.4,12.1,15.9,19.6
8.4,12.1,15.9,19.6 7.8,11.2,14.8,18.3
7.8,11.2,14.8,18.3 6.9,10,13.3,16.4
6.9,10,13.3,16.4
6.1,9.4,12.8,16.3
6.1,9.4,12.8,16.3
6.5,9.8,13.2,16.6
6.5,9.8,13.2,16.6 6.2,9.2,12.2,15.1
6.2,9.2,12.2,15.1
8.2,11.7,15.5,19.1
8.2,11.7,15.5,19.1 7.6,10.9,14.5,17.8
7.6,10.9,14.5,17.8 6.3,9.3,12.3,15.5
6.3,9.3,12.3,15.5
Cat 1, 2, 3, 4 8.4,12.1,16,19.8 8,11.4,15.1,18.6
8.4,12.1,16,19.8 8,11.4,15.1,18.6 7,10.1,13.5,16.6
7,10.1,13.5,16.6 6.4,9.8,13.1,16.5
6.4,9.8,13.1,16.5
7.6,10.9,14.5,17.9
7.6,10.9,14.5,17.9 6,9.1,12.4,15.9
6,9.1,12.4,15.9 99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
The gray cells 8.4,12.1,16,19.7
8.4,12.1,16,19.7 7.9,11.4,15,18.5
7.9,11.4,15,18.5 99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9 6.5,9.9,13.2,16.4
6.5,9.9,13.2,16.4
7.6,11,14.5,17.9
have no surge 8.4,12.1,15.9,19.6
8.4,12.1,15.9,19.6
8.1,11.6,15.3,18.8
8.1,11.6,15.3,18.8
7.6,11,14.5,17.9
5.4,8.3,11.5,14.7
5.4,8.3,11.5,14.7
6.4,9.9,13.5,17.2
6.4,9.9,13.5,17.2
6,9.2,12.3,15.3
6,9.2,12.3,15.3
values 99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
6.8,10.6,14.4,17.8
6.8,10.6,14.4,17.8
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9 99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9 5.6,8.7,12.3,15.9
5.6,8.7,12.3,15.9 5.3,7.8,10.4,12.9
5.3,7.8,10.4,12.9
There are cells 99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
7,11.1,15.1,18.8
7,11.1,15.1,18.8
6.6,10.3,14,17.3
6.6,10.3,14,17.3
6.1,9.3,12.5,15.4
6.1,9.3,12.5,15.4
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
which clearly 99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9
5.3,7.9,10.6,13.2
5.3,7.9,10.6,13.2
would experience
99.9,99.9,99.9,99.9
99.9,99.9,99.9,99.9 5.9,9,12,14.9
5.9,9,12,14.9
6.5,10,13.4,16.7
6.5,10,13.4,16.7
6.9,10.9,14.7,18
6.9,10.9,14.7,18
99.9,12,15.5,19.7
99.9,12,15.5,19.7
99.9,99.9,99.9,99.9 7,11,15.1,20.5
99.9,99.9,99.9,99.9 7,11,15.1,20.5
storm surge, that Storm Surge
5.1,7.6,10.1,12.6
5.1,7.6,10.1,12.6
7.3,11.6,15.1,19
7.3,11.6,15.1,19 6.6,10.1,13.5,16.6 6.1,9.1,12.3,15.1 5.5,8.3,11.1,13.9
6.6,10.1,13.5,16.6 6.1,9.1,12.3,15.1 5.5,8.3,11.1,13.9 Category 4 Heights
have no values 3.5,7.4,13.6,18.1 6.8,11.1,15.2,20.1
3.5,7.4,13.6,18.1 6.8,11.1,15.2,20.1
99.9 to 99.9 (3520)
3.3,7.3,13.5,17.6 7.8,12.2,16.1,19.3
3.3,7.3,13.5,17.6 7.8,12.2,16.1,19.3 24.5 to 99.9 (725)
7,10.9,14.2,17.5 6.4,9.8,13,15.9 5.9,8.9,11.9,14.7
7,10.9,14.2,17.5 6.4,9.8,13,15.9 5.9,8.9,11.9,14.7 18.6 to 24.5 (761)
5.4,8.3,11.2,13.8
5.4,8.3,11.2,13.8 5.1,7.6,10.2,12.6
5.1,7.6,10.2,12.6
12.3 to 18.6 (979) 4.7,6.9,9.2,11.5
4.7,6.9,9.2,11.5
8.3,13,17.3,20.2
8.3,13,17.3,20.2 7.6,11.7,15.5,18.4 4.7 to 12.3 (1313)
7.6,11.7,15.5,18.4 6.6,10.1,13.3,16.1
6.6,10.1,13.3,16.1
5.8,8.8,11.8,14.7 5.4,8.2,11.1,13.7
5.8,8.8,11.8,14.7 5.4,8.2,11.1,13.7
8,12.4,16.5,19.8
8,12.4,16.5,19.8 5.1,7.6,10.2,12.6
5.1,7.6,10.2,12.6
7.2,11,14.5,17.5
7.2,11,14.5,17.5 4.8,7,9.2,11.5
4.8,7,9.2,11.5
6.3,9.5,12.6,15.5
6.3,9.5,12.6,15.5
7.7,11.7,15.5,18.6
7.7,11.7,15.5,18.6 5.5,8.5,11.4,14.1
5.5,8.5,11.4,14.1
Eastern end of Long Island, NY

8. Surge Contours
•The problem isn’t as simple as it seems
•In this illustration, you can see that a location may be inland, but protected by a hill;
but if the water is high enough, it may go over the hill (or levee – think Katrina)
•Just because SLOSH says the water is above the elevation of the location, this does
NOT mean that the property would be inundated; topology matters

9. Surge Contours – Long Island
Storm Surge
By Storm Category
3
4
2
1
Eastern end of Long Island, NY 0

10. What we’ve developed
 We’ve combined the storm surge contours
and SLOSH data
 We’ve filled in the missing SLOSH cells
 We give you the highest values from multiple
basins (users do not have to select a basin)
 If you combine this with the RiskMeter
slope/aspect/elevation report, you can
estimate the water depth at any location!
 This gives the most complete picture of storm
surge effects in an area available today, from
anyone

11. Fields Returned
 Minimum Hurricane Category
 Surge Risk Score
 Surge Height Category 1
 Surge Height Category 2
 Surge Height Category 3
 Surge Height Category 4
 Surge Height Category 5
 Notes

12. How Big is the Problem?
NY/Long Island Example

13. How Big is the Problem?
 New York/Long Island
Population living in a 100 year flood zone: 2,482,038
Population living in a storm surge area: 4,746,434
Population living in a storm surge area and
not recognized as a 100 year flood zone: 2,936,639
 Population based upon storm category:
Category 1: 238,355
Category 2: 524,434
Category 3: 962,823
Category 4: 1,211,027

14. How Big is the Problem?
As you can see, in TX,
storm surge extends
tens of miles inland!

15. Brooklyn/Bronx
Flood Zones
Pink – 100 year flood zones

16. Brooklyn/Bronx
Flood Zones with Surge Model
Pink – 100 year flood zones; dark blue Cat 1 surge; light blue cat 2

17. Brooklyn/Bronx
Flood Zones with Surge Model
and Actual Flooding
Pink – 100 year flood zones; dark blue Cat 1 surge; light blue cat 2
Red – Actual Flooding

18. Actual Flooding
vs. Model
Dark blue Cat 1 surge; Light blue cat 2; Red – Actual Flooding

20. Dark blue Cat 1 surge; Light blue cat 2

21. Dark blue Cat 1 surge; Light blue cat 2; Red – Actual Flooding

22. Dark blue Cat 1 surge; Light blue cat 2; Red – Actual Flooding

23. Dark blue Cat 1 surge; Light blue cat 2; Red – Actual Flooding

24. Dark blue Cat 1 surge; Light blue cat 2; Red – Actual Flooding

25. Staten Island- Actual
Dark blue Cat 1 surge; Light blue cat 2; Red – Actual Flooding

26. Staten Island- Actual
with Surge Model
Dark blue Cat 1 surge; Light blue cat 2; Red – Actual Flooding

27. Southern Manhattan –
Actual
Red – Actual Flooding

28. Southern Manhattan – Actual
With Surge Model
Dark blue Cat 1 surge; Light blue cat 2; Red – Actual Flooding

29. Tip of Manhattan - Actual
Red – Actual Flooding

30. Tip of Manhattan – Actual
With Surge Model
Dark blue Cat 1 surge; Light blue cat 2; Red – Actual Flooding

31. Brooklyn/Bronx - Actual
Red – Actual Flooding

32. Brooklyn/Bronx – Actual
With Surge Model
Dark blue Cat 1 surge; Light blue cat 2; Red – Actual Flooding

33. Coming Improvements
 New SLOSH Data
• ACE has recently released new data
 New Elevation Data
• Updated USGS elevation data

34. Conclusions
 Checking flood maps is not a viable risk
mitigation strategy along the coast
 Surge maps must be used
 The RiskMeter Surge Report was very
accurate at predicting Sandy’s effects
 Customers saved millions of dollars by
referencing these maps

35. Contact Information
If you have any questions, please contact:
Dan Munson
Vice President of Sales & Marketing
617-737-4444
dmunson@cdsys.com