The document discusses proposed amendments to Dennis' flood zone maps. The current maps from 1992 do not accurately reflect topography and provide a false sense of security. New maps being developed since 2009 use updated GIS and LIDAR technologies and better reflect flood risks. The changes would extend base flood elevations to appropriate boundaries, update to a more accurate elevation datum, and result in around 5,000 additional structures being placed in the flood zone. Adopting the new maps is important to maintain eligibility for federal flood insurance and disaster assistance that thousands of properties rely on.

1. Dennis Flood Map Zoning
Amendment
Some Discussion of the Issues

2. Some Facts about the Current Maps
• Last revised 1992
• Pre-date most electronic mapping capabilities
• Do not accurately reflect topography
• Provide a false sense of security for home
owners

3. New Maps
• Revision in process since
2009
• Mapping tied to latest GIS
mapping capabilities
• Topography collected by
latest LIDAR technology
• Maps better reflect historic
flood patterns

4. The Changes
• Maps extend base flood elevations to
appropriate topographical boundaries

5. The Changes
• Modifies Base Flood Elevation from NGVD29
to NAVD88 a more accurate base elevation
• Elevation 0.0 (NAVD88) is about 0.94 ft higher
than it was in 1929 (NGVD29).
• In most cases old flood elevation 11 (for
instance) is now new flood elevation 10.
• Old flood elevation 11 that remain 11 equals a
1 foot increase in water levels.

6. 90% of Changes are due to extending flood
elevations to appropriate contour

7. 90% of Changes are due to extending flood
elevations to appropriate contour

8. 90% of Changes are due to extending flood
elevations to appropriate contour

9. 90% of Changes are due to extending flood
elevations to appropriate contour

10. 90% of Changes are due to extending flood
elevations to appropriate contour

11. 90% of Changes are due to extending flood
elevations to appropriate contour

12. Ultimately the new flood maps will better reflect
hurricane storm surge

13. Putting it Into Perspective
• In 1944, 238 residences in Dennis were
destroyed and an additional 3,898 structures
damaged
• Only 1,133 structures are currently insured or
¼ of the number damaged in 1944
• The new maps will place about 5,000
structures into the flood zone
• Dennis has added 11,000 homes since 1950

14. Why We Need to Adopt These Maps
• Maintain Dennis Eligibility for National Flood
Insurance Program (NFIP)
• Loss of NFIP eligibility will eliminate federally
backed mortgages within the flood zone.
• Over 5,000 properties may be unable to attain
conventional financing

15. Why We Need to Adopt These Maps
• Non-federally backed mortgage companies
will still require some form of flood insurance
• Private flood insurance will cost more than
NFIP backed insurance.

16. Why We Need to Adopt These Maps
• Town will become ineligible for disaster relief
spending such as has gone to Dr. Bottero Road
and elsewhere.
• Town will become ineligible for pre-disaster
relief spending such as is available from time
to time to assist in making homes flood zone
compliant

17. A SIDE NOTE ON NATIONAL FLOOD
INSURANCE PROGRAM CHANGES

18. “The insurance
pool doesn’t just
insure that your
house can be
rebuilt Mary, it
helps Mr. Jones
and Mr. Smith
here too. We all
pay into the NFIP
to be sure we all
have the funds to
rebuild later.”

19. Flood Insurance in Perspective
• 1,133 policies issued in Dennis
• $245,632,900 total premium value
• $1,312,095 in annual payment to NFIP
• Average Premium Value $216,799
• Average Policy Payment $1,158
Source: http://bsa.nfipstat.fema.gov/reports/1011.htm#MAT

20. Flood Insurance in Perspective
• It would take NFIP minimum of 187 years to
recover damages occurring in a 100 year (1%)
storm
• Since 1976 NFIP has paid out $1,450,308 in
damages ($38,166/year)
• Annual average payouts extend NFIP risk
recovery to 192 years
Source: http://bsa.nfipstat.fema.gov/reports/1040.htm#25

21. Flood Insurance in Perspective
• Congress has adopted guidance calling for an
average policy cost cap of 1% of premium
value, in Dennis this would mean $2,167
average insurance costs
• Guidance would mean a $1,010 average
increase phased in over several years
• Average annual premium increase would be
$208 at the 18% maximum cap ($173 increase
at the average recommended increase of 15%)

22. Flood Insurance in Perspective
• HR 3370 provides properties newly mapped to
acquire Preferred Risk Policies prior to July 16
• Preferred Risk Policies can be acquired for
$460 for $250,000 coverage for two years.
• Policy costs will increase by 18% annually
thereafter until full risk

23. More information at:
HR 3370 Discussion
http://dennismaplanningdept.wordpress.com/
Flood Maps Online
http://www.mapsonline.net/dennisma/dennisfema2013.html#