HURRICANE DENNIS

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					   HURRICANE DENNIS
BEACH AND DUNE EROSION AND STRUCTURAL
         DAMAGE ASSESSMENT
                    AND
POST-STORM RECOVERY RECOMMENDATIONS
                  FOR THE
     PANHANDLE COAST OF FLORIDA




          Florida Department of Environmental Protection
          Division of Water Resource Management
          Bureau of Beaches and Coastal Systems
          July 2005
                                                 Table of Contents
FOREWORD ....................................................................................................................... i

I. Hurricane Dennis Impact Summary and Overview ...................................................... 1

II. Beach and Dune Erosion and Summary of Structural Damage.................................... 8
     A. Pensacola Beach, Escambia County ....................................................................... 8
     B. Navarre Beach, Santa Rosa County ...................................................................... 11
     C. Ft. Walton Beach, Okaloosa County..................................................................... 15
     D. Destin, including Holiday Isles, Okaloosa County............................................... 16
     E. Walton County ...................................................................................................... 21
     F. Panama City Beaches, Bay County ...................................................................... 26
     G. Mexico Beach, Bay County .................................................................................. 33
     H. Beacon Hill to Port St. Joe, Gulf County.............................................................. 34
     I. St. Joseph Peninsula, Cape San Blas, and Indian Peninsula, Gulf County........... 34
     J. St. Vincent Island, Franklin County ..................................................................... 39
     K. Cape St. George Island, Franklin County ............................................................. 40
     L. St. George Island (R52-R105), Franklin County .................................................. 40
     M. St. George Island State Park ................................................................................. 41
     N. Dog Island, Franklin County................................................................................. 42
     O. Alligator Point to Bald Point, Franklin County .................................................... 42
     P. Mashes Sands and Ochlockonee Bay, Wakulla County ....................................... 47
     Q. Live Oak Island, Shell Point, Spring Creek, Wakulla Beach, Wakulla County ... 48

III. Recovery Recommendations and Management Strategies ......................................... 48
     A. Area-wide Strategies and Recommendations ....................................................... 48
     B. Site-specific Recommendations............................................................................ 49
        Escambia County .................................................................................................. 49
        Santa Rosa County................................................................................................ 49
        Okaloosa County................................................................................................... 49
        Walton County ...................................................................................................... 49
        Bay County ........................................................................................................... 50
        Gulf County .......................................................................................................... 50
        Franklin County .................................................................................................... 50
        Wakulla County .................................................................................................... 51
                                    FOREWORD
The Bureau of Beaches and Coastal Systems of the Florida Department of Environmental
Protection (FDEP) is responsible for the protection and management of the sandy beaches
of Florida fronting the Gulf of Mexico, Atlantic Ocean, and Straits of Florida, and the
regulation of coastal development adjacent to the barrier beaches. The monitoring and
assessment of coastal storm and hurricane impact to the State’s beaches and coastal
construction and recommendations for post-storm response and management strategies
are an important part of that responsibility.

This report provides an initial assessment of damages to the beaches and dunes and
coastal construction of the Panhandle region of Florida’s coast as a result of Hurricane
Dennis and provides preliminary recommendations for post-storm response activities.
This report was prepared by the Bureau’s Coastal Engineering Section with assistance
from Florida State University’s Beaches and Shores Resource Center.

Subsequent damage assessment reports will be prepared as topographic and bathymetric
survey data to quantify the erosional impact of Hurricane Dennis becomes available, and
as additional information is received regarding structural damage to upland development.




                                             APPROVED BY



                                             Michael R. Barnett, P.E., Chief
                                             Bureau of Beaches and Coastal Systems




                                             i
I.        Hurricane Dennis Impact Summary and Overview
Hurricane Dennis, like Hurricane Ivan less than a year earlier in September 2004 and
Hurricane Opal in 1995, was one of the most destructive hurricanes to impact Florida’s
Panhandle coast in recorded history. After reaching Category 4 strength in the northern
Gulf of Mexico as it approached the Florida Panhandle coast, Dennis made landfall east
of Pensacola Beach, Florida, near Navarre Beach in the early afternoon of July 10, 2005,
as a Category 3 hurricane with wind speeds reported at 115-120 m.p.h. A graphic
depiction of Dennis’ path and associated storm intensity through the Caribbean Sea and
Gulf of Mexico and into the southeastern United States is shown in Figure 1.

As Dennis made landfall, the greatest convection and strongest winds associated with the
hurricane were located east-northeast of the storm center. This aspect of the storm
coupled with the higher, onshore-directed winds and associated storm surge and
accompanying breaking waves resulted in much of Dennis’ most destructive impact
occurring in areas east of its point of landfall. As a result, coastal areas from Navarre
Beach through Wakulla County sustained severe impact from Dennis.




     Figure 1. Hurricane Dennis storm track with landfall on western Florida Panhandle Coast
               (Source: CIMSS/Univ. of Wisconsin-Madison via NOAA / NCEP / TPC).

Initial estimates of storm tide with associated wave action along coastal regions of the
western Panhandle were reported to be on the order of +10 to 12 feet above mean sea
level, similar to, but not as high as, Ivan or Opal. The National Ocean Survey (NOS) tide

                                          Page 1 of 51
gage located nearshore at the Panama City Beach pier, approximately 70 miles east of the
location of Dennis’ landfall, provided water level data for Hurricane Dennis. Peak water
levels at the gage reached near +7 feet MLLW (approximately 6.5 feet NAVD88).
Addition of wave setup effects would translate to expected storm tide and wave impact
elevations reaching approximately 10 feet above mean sea level along shorefront areas in
Panama City Beach. Acquisition of surveyed high water marks by FDEP established
approximate storm tide elevations in Okaloosa, Bay, Gulf, and Franklin Counties. A
graphic plot of the NOS storm tide data for Hurricane Dennis from the Panama City
Beach pier (Station 8729210) is provided in Figure 2 below. Storm tide data from
Hurricane Ivan and Hurricane Opal obtained from the same NOS station in Panama City
Beach is included for comparison purposes.




  Figure 2. NOAA-NOS Storm Tide Elevations - Hurricanes Dennis, Ivan, and Opal.


The trajectory of Dennis’ path, tracking relatively close to the Gulf Coast of Florida,
resulted in onshore-directed wind stress in the northeastern Gulf of Mexico creating
extremely high storm tide associated water levels in open coast and interior bay areas of
Franklin and Wakulla counties, on the order of 8-10 feet above normal elevations.


                                       Page 2 of 51
Extensive flooding occurred throughout these areas including St. Marks, Shell Point,
Alligator Point, Lanark, Carrabelle, and Eastpoint.

Wave heights recorded by NOAA wave buoy station 42039, located approximately 125
miles southeast of Pensacola Beach, Florida, in a water depth of 956 feet, reached 35 feet
as shown in the NOAA graph in Figure 3 below. Wind and air pressure graphic plots
obtained from NOAA for the Panama City Beach pier station (NOS#8729210,
NOAA#PCBF1), and for Station PCLF1 in Pensacola Bay, the latter of which is located
approximately 15 miles from the landfall location of Dennis, are shown in Figures 4 and
5 below. This data should be considered as preliminary data and is not considered to
represent the maximum or best representative peak values for Hurricane Dennis.

This report provides an initial assessment of storm impact, beach and dune erosion, and
structural damages to the coastal regions of the Florida Panhandle. Although extensive
structural damage occurred well inland of the Gulf of Mexico coast, the damage
assessment in this report will specifically focus on the coastal areas seaward of the state’s
Coastal Construction Control Lines (CCCL’s) and the Coastal Building Zone. The
CCCL’s are located along the sandy beach coast as set forth in Chapter 161, Florida
Statutes, as the area of regulatory jurisdiction of the FDEP Bureau of Beaches and
Coastal Systems. The Coastal Building Zone is the land area from the seasonal high-
water line landward to a line 1,500 feet from the CCCL. It is noteworthy that, while
wave-induced impacts from Hurricane Dennis were also sustained along the Florida
Keys, and central and southwest Gulf of Mexico coast of Florida, such impacts are not
specifically addressed in this report.

An overall summary of beach/dune erosion and structural damage is given in Table 1 and
2 below where the discussion of the beach and dune erosion conditions using a qualitative
scale provided by Clark (1981) as shown in Figure 6. A more detailed description of
these impacts by specific location is provided in Section II of this report.




                                        Page 3 of 51
                                                            Figure 3. Wave Heights from
                                                                      Hurricane Dennis
                                                                      (measured at NOAA-NDBC
                                                                      buoy # 42039 located
                                                                      approximately 125 miles SE
                                                                      of Pensacola).




Figure 4. Wind Speed and Air Pressure
          from Hurricane Dennis
          (measured at NOAA-NDBC
          station # PCLF1 located in
          Pensacola approx. 15 miles
          from Dennis’ landfall).




                                                       Figure 5. Wind Speed and Air
                                                                 Pressure from Hurricane Dennis
                                                                 (measured at NOAA-NDBC
                                                                 station # PCBF1 located in
                                                                 Panama City Beach approx. 70
                                                                 miles from Dennis’ landfall).




                                        Page 4 of 51
          Table 1. Beach and Dune Erosion Summary
County                                          Erosion Condition
Escambia
    Pensacola Beach (R107-R151)                    I (Minor)
Santa Rosa
    Navarre Beach (R192-R210)                      IV (Major)
Okaloosa
    Ft. Walton Beach (R1-R16)                      III-IV (Major)
    Destin & Holiday Isle (R17-R50)                IV (Major)
Walton
    County-wide                                    IV (Major)
Bay
    Panama City Beaches (R1-R37)                   IV (Major)
    Panama City Beaches (R37-R77)                  II-III (Moderate)
    Panama City Beaches (R77-R93)                  III (Moderate)
    St. Andrews State Park (R91-R97)               II (Minor)
    Mexico Beach (R128-R144)                       II (Minor)
Gulf
    Beacon Hill, Port St. Joe Beach (R1-R30)       I (Minor)
    St. Joseph Peninsula (R32-R105)                IV (Major)
    Cape San Blas (R105-R127)                      IV (Major)
    Indian Peninsula (R127-R159)                   III (Moderate)
    Indian Pass Beach (R159-R161)                  IV (Major)
Franklin
    St. Vincent Island                             IV (Major)
    Cape St. George Island (R1-R51)                IV (Major)
    St. George Island (R52-R149)                   IV (Major)
    Dog Island (R150-R193)                         IV (Major)
    Alligator Point to Bald Point (R194-R239)      IV (Major)
Wakulla
    Mashes Sands                                   IV (Major)
    Shell Point                                    II (Minor)




                              Page 5 of 51
                  Table 2. Summary of Major Structural Damages
                  (Seaward of Coastal Construction Control Line)
                            Buildings Destroyed      Nonhabitable Major        Wall/Revetment
                                    or               Structures Destroyed        Destroyed
                              Major Damage                    or                     or
County                       SFD        MFD             Major Damage           Major Damage
Escambia
 Pensacola Beach                8           3                   0                      0
Santa Rosa
  Navarre Beach                 29          25                  3                      7
Okaloosa
 Ft. Walton Beach               2            5                  1                      3
 Destin & Holiday Isle          5           17                  4                     13
Walton                          24          2                   7                      4
Bay                             0           0                   0                      0
Gulf
 St. Joseph Peninsula
 (R32-R105)                     3           3                   0                      1
Franklin
  St. George Island              5          0                   5                      1
  Dog Island                    15          0                   0                      3
  Alligator Point to Bald       23          0                   2                      8
  Point
                    Total      114          55                 22                     40
Note 1: The detailed damage assessments in Section II of this report includes the number of
         major habitable structures located within the Coastal Building Zone, which were
         destroyed or sustained major damage.
Note 2: The specific locations given in Table 1 and 2 above include FDEP range locations,
        shown as R number locations, which are located approximately every 1,000 ft along the
        sandy beach shorelines of the Gulf of Mexico, Straits of Florida and Atlantic Ocean in
        Florida.
Note 3: SFD and MFD above represent single- and multi-family dwelling, respectively




                                         Page 6 of 51
Figure 6. Qualitative scale for beach and dune erosion conditions.


                                      Page 7 of 51
II.    Beach and Dune Erosion and Summary of Structural Damage

A.     Pensacola Beach, Escambia County
At about 2:25 PM CDT, July 10, Hurricane Dennis made landfall approximately two
miles east of Pensacola Beach near Big Sabine Point on Santa Rosa Island. Pensacola
Beach was generally in the weaker leeside eye-wall and experienced winds in probably
the category II range (95-115 mph). A peak wind of 93 mph was measured in Pensacola
by the National Weather Service. The strongest winds appeared to have occurred from
the northwest immediately following landfall of Dennis’s eye. Storm tides of eight to ten
feet affected the area with wave energy both from the gulf and the sound.

Minor beach erosion (condition I) was sustained along Pensacola Beach. The erosion did
not leave any scarping, and new constructed dunes were not significantly damaged. A
major beach restoration project was completed here in 2003, and the Santa Rosa Island
Authority was in the process of nourishing the beach to pre-Ivan design. Follow-up beach
profile surveys through the beach restoration project area may quantity greater erosion
impacts than were observed.

Moderate to severe wind damage was experienced throughout Pensacola Beach with the
damage being greater towards the eastern end of the community, closer to the eye. Most
wind damage was caused by northwesterly winds, and typically the north and west facing
sides of structures revealed the greatest damage. Over one half of the structures having
major damage sustained major wind damage.

Storm surge flooding was not as severe during Dennis as occurred during Hurricanes
Opal (1995) and Ivan (2004). Most of the gulf-front structures susceptible to storm surge
damage had been destroyed and removed following Opal and Ivan. A number of
structures flooded and damaged by prior storms and located in the second or greater row
of construction landward from the beach were damaged again by Dennis. Several
slab on-grade structures located along the Santa Rosa Sound shore were destroyed by
storm surge and waves coming from the waters of the sound. The gulf fishing pier
remained structurally intact, however, the breakaway pier deck panels were blown out by
wave uplift forces along much of its length.

Throughout Pensacola Beach within the coastal building zone, 114 major structures
sustained major damage, including 22 structures that were destroyed. Of these, 11 major
structures located seaward of the established Coastal Construction Control Line (CCCL)
sustained major damage. In addition, 15 major structures sustained understructure
damage. The overall damage sustained was less than occurred during Hurricanes Opal
and Ivan, and comparable to Hurricane Frederic (1979).




                                      Page 8 of 51
Figure 7. Escambia County Location Map.




                                    Page 9 of 51
Photo 1.   Destroyed dwelling, Pensacola Beach.




                           Page 10 of 51
B.     Navarre Beach, Santa Rosa County
The center of the eye of Hurricane Dennis made landfall about 7.5 miles west of Navarre
Beach placing this Santa Rosa Island community within the eye-wall of highest winds. A
maximum wind velocity of 121 mph was measured at Navarre Beach and 110 mph at the
Loop Tower on Eglin Air Force Base, 5.3 miles east of Navarre Beach State Park. The
maximum winds impacted Navarre Beach from the south-southeast. An estimated storm
tide of 10 to 12 feet caused extensive flooding and overwash across the island
comparable to the impact of Hurricanes Opal and Ivan.

Major beach and dune erosion (condition IV) was sustained throughout Navarre Beach
and adjoining areas. Few dunes, natural or man-made, survived the impact of Dennis.
Scour of the beach and upland contours significantly lowered elevations by of three to six
feet. The beach is now very narrow throughout Navarre Beach and a number of
structures are encroaching on the foreshore slope close to normal high tides.

Moderate to severe wind damage was experienced throughout Navarre Beach. About
three-fourths of the damaged structures sustained major wind damage. Substantial
damages were sustained due to the storm surge and waves in addition to the wind loads
and erosion/scour. Many pile supported structures have lost significant embedment depth
of their foundation piles. Inadequate embedment depth was associated with the damage
to several structures.

The extensive flooding and overwash severely damaged the roads and utilities. Beach
access walkways have been destroyed throughout the community. The Navarre Fishing
Pier sustained complete destruction to two sections. And the recently completed Navarre
Beach State Park was severely impacted having all its dunes, roads, paved parking areas,
boardwalks and beach access walkways, and one large bathhouse/concession building
destroyed.

Throughout Navarre Beach, 130 major structures sustained major damage, including 26
major structures that were destroyed. Of these, 57 major structures located seaward of
the established Coastal Construction Control Line (CCCL) sustained major damage.In
addition, 97 major structures sustained understructure damage, and 1,565 feet of retaining
walls and bulkheads were destroyed. The overall damage sustained was comparable to
that which occurred during Opal and Ivan.




                                      Page 11 of 51
Figure 8. Santa Rosa County Location Map.




                                 Page 12 of 51
Photo 2.   Damage to Navarre Fishing Pier (R209).




Photo 3.   Bathhouse destroyed at Navarre Beach State Park (R213).

                               Page 13 of 51
Photo 4.   Dwelling destroyed (R193).




                      Dwelling destroyed
                           from photo 4




Photo 5.   Damage along Gulf Boulevard (R192.5).

                                Page 14 of 51
C.     Ft. Walton Beach, Okaloosa County
The developed beach area of Okaloosa County adjacent to Ft. Walton Beach was
25 miles east of the eye of Hurricane Dennis at landfall. A maximum wind velocity of
102 mph was recorded nearby in Mary Esther. An estimated storm surge of between 8 to
10 feet impacted this area of Santa Rosa Island.

Moderate to major beach and dune erosion (condition III – IV) was sustained throughout
this area. The extensive flooding and overwash seen in this area during Opal and Ivan
did not occur during Dennis. Unlike after Opal and Ivan, the roads were not covered with
sand except for street ends in close proximity to the beach. The beach remains wide and
will support post-storm recovery dune restoration projects.

Only minor to moderate wind damage was sustained throughout the community. A few
structures not conforming to elevation standards of the current building code sustained
repeat first floor damages due to the storm surge. A number of structures were flooded
and sanded on their first floor interiors. Several swimming pools were filled with sand
(see Photo 6). The Okaloosa County fishing pier sustained no apparent damage.

Throughout the Santa Rosa Island section of Okaloosa County, 11 major structures
sustained major damage. Of these, 8 major structures located seaward of the established
CCCL sustained major damage. No major structures were destroyed. In addition, 170
feet of retaining walls were destroyed.




       Photo 6.    Pool sanded, Okaloosa County.


                                     Page 15 of 51
D.     Destin, including Holiday Isles, Okaloosa County
The City of Destin was 32 miles east of the eye of Hurricane Dennis at landfall. A
maximum wind velocity of 74 mph was measured in Destin, indicating the winds were
generally below hurricane strength in the area. An estimated storm surge of between 8 to
10 feet impacted Destin. The landward extent of wave run-up surveyed by FDEP at
reference monument R27 was approximately 370 feet landward of the mean high-water
shoreline at an elevation of +10.9 feet (NAVD88).

Major beach and dune erosion (condition IV) was sustained throughout Destin (see
Figure 7). The road and development within the critically eroded area of eastern Destin
between R39 and R50 is in need of constructing the funded beach restoration project.
Significant flooding was sustained in the Lands End Drive area of Holiday Isles and was
perhaps worse than the flooding sustained during Ivan. Given this area was submerged
lands of the Gulf of Mexico only 40 years ago, and remains a lagoonal depression today,
the potential for flooding is greater.

Elsewhere in Destin, the flooding was not as severe as during Opal or Ivan, and the
damages were substantially less. There was no damage in the Norriego Point area where
Opal caused a severe impact. The winds and wave attack from Dennis were out of the
southeast in this area and the east jetty to East Pass sheltered the Norriego Point
development from any significant damage.

Only minor to moderate wind damage was sustained throughout Destin. A number of the
same nonconforming structures damaged by Opal or Ivan and subsequently repaired, saw
repeat damage from Dennis. Pools were impacted with sand and all the beach fronting
retaining walls were destroyed.

Throughout Destin, 35 major structures sustained major damage, with only one
destroyed. Of these, 26 major structures located seaward of the established Coastal
Construction Control Line (CCCL) sustained major damage. In addition, 18 major
structures sustained understructure damage, and 2,405 feet of retaining walls were
destroyed or damaged. Overall, the damage from Dennis in Okaloosa County was about
one-fourth the damage seen during Opal or Ivan. Examples of damages in this area are
shown in photos 7-10.




                                     Page 16 of 51
Figure 9. Okaloosa County Location Map.




                                  Page 17 of 51
                                  25



                                  20



                                  15



                                  10



                                   5




           ELEVATION (FT. NAVD)
                                   0




Page 18 of 51
                                   -5



                                  -10
                                     -50             0             50             100       150     200        250                  300      350   400
                                                                                  DISTANCE FROM MONUMENT (FEET)


                                                   BEACH PROFILE                                 OKALOOSA
                                                     18JUL05-POST-DENNIS
                                                                                                                               RANGE: R-39
                                                     00NOV04-PRE-DENNIS               BUREAU OF BEACHES & COASTAL SYSTEMS
                                                                                      FLA. DEPT OF ENVIRONMENTAL PROTECTIONS
                                                                                                                               BEARING: 185.00
                                                     18JUN04-PRE-IVAN

                                  Figure 10. Okaloosa County before and after beach profile (R39).
Photo 7.   Roof damage, Sandpiper Cove (R24.5).




Photo 8.   Dwelling undermined (R44.5).

                             Page 19 of 51
Photo 9.   Concrete wall failure and building undermined (R45).




 Photo 10. Dwelling destroyed (R49).

                              Page 20 of 51
E.     Walton County
The entire coast of Walton County sustained major beach and dune erosion (condition
IV) and major damage to numerous structures from the impact of Hurricane Dennis. The
erosion impact was comparable to the impact of Hurricanes Eloise (1975), Opal (1995),
and Ivan (2004). The impact of Dennis exacerbated the severe erosion conditions which
had not recovered from last year.

As the case has been since the impact of Hurricane Ivan last year, the existing eroded
conditions of the beach and dune system leaves many private structures and public
infrastructure vulnerable to damage from the impact of high-frequency coastal storms.

Following Hurricane Ivan, 5.1 miles of beaches in Walton County were added to the 6.8
miles of beaches that were designated as critically eroded. A critically eroded area is a
segment of the shoreline where natural processes or human activity have caused or
contributed to erosion and recession of the beach or dune system to such a degree that
upland development, recreational interests, wildlife habitat, or important cultural
resources are threatened or lost. Specific locations where development appears to be
within close proximity (< 10-20 feet) to the dune bluff and thus in a vulnerable condition
are listed by reference monument locations below. This list is essentially an expansion of
the areas currently designated as critically eroded following Hurricane Ivan due to the
additional erosion of Hurricane Dennis.
       Western Walton County (R1-R22.8)
       Beach Highlands/Dune Allen (R41-R54.5)
       Blue Mountain Beach (R58-R63)
       Gulf Trace (R67.3-R68.3)
       Grayton Beach (R71-100-R71.3)
       Seagrove Beach (R82-R97 except the Eastern Lake outlet (R94.5-R95). Currently
       the designated area is R82-R90.1.
       Seacrest Beach (R106-R114.7). Currently the designated area is R109.5-R114.7.
       Dana Beach (R116-R119). Currently this area is not designated.
       Rosemary Beach (R116-R121). Currently this area is not designated.
       Inlet Beach (R122-R127). Currently the designated area is R122-R124.

There are a number of coastal lake outlets that flow intermittently across the beach
throughout Walton County. Following Hurricane Dennis, as also occurred following past
hurricanes, most all of these outlets were flowing freely into the gulf. The exception was
at Oyster Lake where overwash sand and debris filled in the channel and box culvert
located under County Road C30A.

Major structural damage was sustained along Walton County’s coast and was related to
storm surge and waves undermining dwellings supported on foundations that do not
conform to current building code standards. Major damage to nonhabitable
understructure enclosures and appurtenant structures was also due to storm surge and
waves. Wind damage to structures was not observed. In addition, many older dwelling
structures that are located at the top of the steep, eroded dune bluff are in imminent
danger of structural damage as the soil beneath the concrete slab foundations slips down
the unstable slope. Along several areas, the dune bluff recession leaves many pile-
                                      Page 21 of 51
supported dwellings sited on the beach. Erosion now threatens the upland access and
utility connections to these gulf-front properties, as well as the upland public
infrastructure. Dana Beach (R116-R119) and Rosemary Beach (R119-R121) were
critically eroded and could have been damaged more had the underlying peat strata not
been present.

A total of 11 single-family dwellings and seven nonhabitable major structures (six
swimming pools and one garage) were destroyed. All these structures were sited seaward
of the established CCCL. Another 13 single-family dwellings and 2 multifamily
dwellings sustained major damage to their nonconforming foundations. These structures
were also sited seaward of the CCCL. Additionally, 25 dwellings supported on
nonconforming foundations are in imminent danger of structural damage as the soil
beneath the concrete slab foundations slips down the unstable slope of the eroded dune
bluff. In addition, a total of 19 habitable structures sustained moderate to major damage
to nonhabitable understructure enclosures. Also, 400 feet of retaining walls were
destroyed or sustained major damage. Examples of damages in this area are shown in
photos 11-15.




      Photo 11. Dwelling destroyed (R9).




                                     Page 22 of 51
Figure 11. Walton County Location Map.




                                   Page 23 of 51
Photo 12. Destroyed retaining wall (R10).




 Photo 13. Imminently threatened structure, Blue Mountain Beach (R60).




                             Page 24 of 51
Photo 14. Damaged structure, Gulf Trace (R68).




 Photo 15. Dwelling destroyed, Inlet Beach (R123).



                            Page 25 of 51
F.     Panama City Beaches, Bay County
In April 1999, a large-scale beach and dune restoration project was completed from the
Walton/Bay county line (R1) east to St. Andrews State Park pier (R93). Erosion of the
restored beach and dune system by Hurricane Dennis was significant, and with the
cumulative impact from Hurricane Ivan, the beach and dune system is in a severely
eroded condition along much of the coast. The landward extent of wave run-up surveyed
by FDEP at reference R19 was approximately 180 feet landward of the mean high-water
shoreline at an elevation of +10.6 (NAVD88).

The approximately 1 mile segment of shoreline immediately adjacent to the Walton
County line (R1-R5) sustained major dune erosion (condition IV). The beach sustained
moderate erosion by Hurricane Ivan that left it vulnerable to a major hurricane such as
Dennis (See Photos 19 & 20).

In response to the erosion caused by Hurricane Ivan, an interim beach nourishment
project began in April of this year to partially restore the project. Prior to the impact of
Dennis, approximately 4.6 miles of beach in western Bay County (R5 to R30) had been
replenished with sand from offshore borrow areas. Much, if not all, of this material was
removed from the beach during Dennis such that the existing elevation of the beach is
significantly lower than the +7.0 feet NGVD construction elevation (see Figure 8). This
severely eroded condition of the beach extends eastward to approximately R37 (See
Photos 21 & 22).

The central segment of the Panama City Beaches Restoration Project (R37 to R77)
experienced moderate beach erosion. Although the existing beach width is significantly
less than the 1999 beach width after construction of the beach restoration project, the
existing elevation of the berm does not appear to be significantly lower than the
construction elevation, and still provides a measure of storm protection to the upland
development against high-frequency storm events.

The eastern segment of the Panama City Beaches Restoration Project (R77-R93)
experienced moderate beach erosion in terms of beach profile lowering during Dennis.
The existing elevation of the berm is significantly lower than the 1999 constructed
elevation, which is partially attributable to the cumulative impacts of Ivan and Dennis.
Interim beach nourishment was under construction during the first of July this year to
partially restore the project. Prior to the impact of Dennis, nearly one mile of beach
(R92-R87) had been replenished with sand from offshore borrow areas, which included
the Spyglass Drive area. Had this area not been nourished it is likely that structural
damage to dwellings and Spyglass Drive itself would have occurred (See Photos 16, 17 &
18).

Bay County sustained minor damage to structures located along the western portion of
the county. The first floor apartments of ten multifamily dwelling structures (total of 31
units) were flooded and sustained water damage to drywall and contents. One swimming
pool was destroyed near the western end of the county. The concrete Panama City Beach
fishing pier (R40.5), damaged by Ivan, sustained additional damage from Dennis. The
Bay County pier is to be assessed for damages. Numerous storm water outlet structures

                                       Page 26 of 51
that are sited on the backshore beach (a free-standing concrete dispersion box attached to
the end of an outfall pipe) were toppled and sustained minor damage. All damages were
seaward of the established CCCL.

At St. Andrews State Park (R91-R97) the beach was nourished with a substantial volume
of sand excavated from Panama City Harbor maintenance dredging the year prior to the
impact of Ivan. Significant lowering of the nourished beach elevations occurred as a
result of Ivan, but the project protected upland park facilities from major damage. Dennis
caused minor beach erosion along the gulf shore of the park and no structural damage to
park facilities. The protective sand berm along the St. Andrews Inlet shoreline prevented
erosion of upland park property and adverse impact to Gator Lake.




                                      Page 27 of 51
Figure 12. Bay County Location Map.




                                Page 28 of 51
                                  25



                                  20



                                  15



                                  10



                                   5




           ELEVATION (FT. NAVD)
                                   0




Page 29 of 51
                                   -5



                                  -10
                                     -50             0             50             100       150     200        250                   300      350   400
                                                                                  DISTANCE FROM MONUMENT (FEET)


                                                   BEACH PROFILE                                      BAY
                                                     19JUL05-POST-DENNIS
                                                                                                                                RANGE: R-18
                                                     08OCT04-PRE-DENNIS                BUREAU OF BEACHES & COASTAL SYSTEMS
                                                                                       FLA. DEPT OF ENVIRONMENTAL PROTECTIONS
                                                                                                                                BEARING: 212.00
                                                     24JUN04-PRE-IVAN


                                  Figure 13. Bay County before and after beach profile (R18).
 Photo 16. About 20 feet of dune erosion (R2.5).




Photo 17. Major beach and dune erosion (R4).

                            Page 30 of 51
Photo 18. Destroyed outfall system (R11).




Photo 19. Dune erosion (R13).

                         Page 31 of 51
                                                          Photo 20.     Pre-Nourishment Beach
                                                                        Profile.




Photo 21.   Post-Nourishment Beach
            Profile.




                                                            Photo 22.   Post-Hurricane Dennis
                                                                        Beach Profile.




                Photos Courtesy of Bay County Tourist Development Council

                                       Page 32 of 51
G.     Mexico Beach, Bay County
Mexico Beach Inlet at the west end of the Town of Mexico Beach, was about 105 miles
east of the eye of Dennis at landfall. Winds possibly reached tropical storm strength in
this community, however, very little impact was sustained by the wind. An estimated
storm surge of 6 to 8 feet may have affected this area which was generally sheltered by
St. Joseph Peninsula from the southeast waves and wind of Dennis.

Minor beach and dune erosion (condition II) was generally sustained throughout Mexico
Beach. The beach remains wide and will support post-storm recovery dune restoration or
revegetation projects.

Throughout Mexico Beach no major damage was seen, however, the entrance to Mexico
Beach Inlet was completely sanded in obstructing any navigable access to or from the
harbor. The outlet at the east end of Mexico Beach (R137) was likewise inundated with
sand.




 Photo 23. Entrance shoaling in Mexico Beach Inlet (R127.7).




                                      Page 33 of 51
H.     Beacon Hill to Port St. Joe, Gulf County
East of Mexico Beach, the mainland coast of Gulf County sustained very little impact
from Dennis. Minor beach and dune erosion (condition II) prevailed in this area and no
major damage to buildings was sustained. A coastal high water mark at elevation
+5.5 feet (NAVD88) measured by FDEP at reference monument R28 indicates the storm
surge elevation in this area. This area was sheltered from Dennis’s southeast waves by
St. Joseph Peninsula. A shoreline segment of U.S. Highway 98 sustained road shoulder
and revetment damage west of Port St. Joe.


I.     St. Joseph Peninsula, Cape San Blas, and Indian Peninsula, Gulf
       County
Major beach and dune erosion (condition IV) was sustained throughout St. Joseph
Peninsula. The impact was comparable to past storm erosion impacts from Hurricanes
Eloise (1975), Kate (1985), Opal (1995), Earl (1998) and Ivan (2004).

At the St. Joseph Peninsula State Park major beach and dune erosion was sustained (see
Figure 15). A dune breach was sustained near R69 and the storm surge flooding and
overwash destroyed between 30 and 40 of the park’s camp sites. This area is in critical
need of a dune breach closure project.

Along the developed segment of St. Joseph Peninsula between the state park (R75) and
Stump Hole (R105), six major structures sustained major damage. All major damage was
to the foundation piles due to erosion and wave loads. Approximately 24 major
structures sustained understructure damage. All structures were sited seaward of the
CCCL.

At Stump Hole, between Cape San Blas and St. Joseph Peninsula, storm tide flooding
occurred during both Tropical Storm Arlene and Hurricane Dennis. Waves from both
storms battered the revetment causing rock displacement and damage. Storm tides from
both storms flooded the road and additional road damage was caused by Dennis.

Cape San Blas erodes at about 40 feet per year. With every passing storm severe erosion
is experienced. On June 11, Tropical Storm Arlene inflicted another approximately 25
feet of bluff recession at the Cape San Blas Lighthouse. With Hurricane Dennis, another
100 feet or so of erosion was sustained. This area is the most severely eroding area in
Florida.

Between Cape San Blas and Indian Pass, moderate beach and dune erosion (condition III)
was sustained. Between R159 and R161 at Indian Pass, major beach and dune erosion
(condition IV) was sustained.




                                     Page 34 of 51
Figure 14. Gulf County Location Map.




                                   Page 35 of 51
                                       25



                                       20



                                       15



                                       10



                                        5




                ELEVATION (FT. NAVD)
                                        0




Page 36 of 51
                                        -5



                                       -10
                                          -50               0             50            100       150     200        250                  300      350   400
                                                                                        DISTANCE FROM MONUMENT (FEET)


                                                          BEACH PROFILE                                     GULF
                                                            18JUL05-POST-DENNIS
                                                                                                                                     RANGE: R-70
                                                            08OCT04-PRE-DENNIS              BUREAU OF BEACHES & COASTAL SYSTEMS
                                                                                            FLA. DEPT OF ENVIRONMENTAL PROTECTIONS
                                                                                                                                     BEARING: 255.00
                                                            00APR04-PRE-IVAN

                                             Figure 15. Gulf County before and after beach profile (R70).
Photo 24. Dune breach at St Joseph State Park (R69).




Photo 25. Undermined building with piles suspended (R90.8).



                           Page 37 of 51
Photo 26. Imminently threatened structure (R91).




                           Page 38 of 51
J.       St. Vincent Island, Franklin County
Along St. Vincent Island, major beach and dune erosion (condition IV) was sustained.
The entire island is a National Wildlife Refuge managed by the US Fish and Wildlife
Service.




     Figure 16. Franklin County Location Map.


                                       Page 39 of 51
K.     Cape St. George Island, Franklin County
Between West Pass and Sike’s Cut, major beach and dune erosion (condition IV) was
sustained. Storm tides overwashed the island at numerous locations. At Sike’s Cut, both
inlet jetties have been detached from the islands in a condition comparable to that which
occurred during Hurricanes Elena and Kate (1985). The east jetty was damaged at its
north end.




       Photo 27. Detached jetties at Bob Sike’s Cut (R51.5).



L.     St. George Island (R52-R105), Franklin County
The developed ten miles of St. George Island lies between 163 and 173 miles east of the
point of landfall of the eye of Hurricane Dennis. Storm tides of 10 to 12 feet were
reported in this area. Major beach and dune erosion (condition IV) was sustained for
most of the island. Foredunes and beach access walkways were destroyed throughout the
area. Five single-family dwellings sustained major damage from the storm surge and
erosion, all sited seaward of the CCCL. Numerous grade level structures sustained
flooding and five pile-supported beach front dwellings sustained understucture damage.




                                      Page 40 of 51
M.      St. George Island State Park
St. George Island State Park lies between 173 and 182 miles east of the point of landfall
of the eye of Hurricane Dennis. Storm tides of 10 to 12 feet were observed in this area
and major beach and dune erosion (condition IV) was sustained throughout the park.
Five major structures (the park office and four public bathhouses) sustained major
damage due to the uplift forces of waves on the storm surge and waves. A coastal high
water mark at elevation +7.3 feet (NAVD88) measured by FDEP at the shop building
indicates the storm surge in this area. Most of the boardwalks and decks were damaged or
destroyed at the two day use areas at East Slough and Sugar Hill. Between Sugar Hill
(R128) and the park entrance (R105) all the dunes seaward of the park road were leveled.
Most of the beach access walkways were destroyed and all beach access parking areas
and the park road were covered with sand. The large parking lots at the East Slough and
Sugar Hill day use areas were likewise covered with sand. The eastern four miles of park
beyond the Sugar Hill day use area were completely inundated by the storm tide and
severe leveling of the dune system occurred throughout. As sand removal operations
continue, the segments of park road destroyed will be determined.




                                                                   Photo 28.
                                                                   St George Island
                                                                   State Park, Sugar
                                                                   Hill day use area
                                                                   after Ivan (R117.5).




Photo 29.
St George Island
State Park, Sugar
Hill day use after
Dennis (R117.5).




                                     Page 41 of 51
N.     Dog Island, Franklin County
Dog Island lies between 184 and 190 miles east of the point of landfall of the eye of
Hurricane Dennis. Storm tides of 10 to 12 feet were observed in this area and major
beach and dune erosion (condition IV) was sustained throughout the island. The western
“Narrows” (R156-R160) and eastern “Narrows” (R163-R168) were inundated by the
storm tide and all dunes in these areas were leveled with significant overwash into St.
George Sound.

At least fifteen (15) single-family dwellings sustained major damage with at least seven
of these being destroyed, all seaward of the established CCCL. Approximately 20 or
more dwellings are now critically imperiled by the severe beach and dune erosion. In
addition, 200 feet of wooden bulkhead were destroyed and another approximately 200
feet were damaged and rendered functionless. Damage assessments are ongoing in this
area.




Photo 30. Dwelling Destroyed, Dog Island.


O.     Alligator Point to Bald Point, Franklin County
The Alligator Point to Bald Point portion of Franklin County (R194-R239) sustained
major beach and dune erosion (condition IV) from the impact of Hurricane Dennis. The
erosion and damage was comparable to the impacts of Hurricanes Elena and Kate (1985),
but less than Hurricane Agnes (1972). Although directly impacted by Tropical Storm
Bonnie (2004), little significant erosion was sustained by Bonnie, Hurricane Ivan, or
Tropical Storm Arlene last month. Even though Dennis made landfall over 200 miles to

                                      Page 42 of 51
the west, as did Ivan and Arlene, the path of Dennis (generally from southeast to
northwest) and its large outer rain band resulted in a higher storm surge and waves that
greatly exceeded those of Ivan or Arlene on this shoreline.

Alligator Point to Bald Point sustained major structural damages, including 23 habitable
major structures, all single-family dwellings, and two nonhabitable major structures
(garages) all seaward of the established CCCL. In addition, a total of 37 habitable major
structures sustained major to moderate damage to nonhabitable understructure areas.
Also, 450 feet of retaining walls were destroyed or sustained major damage. The rock
revetment and county road C30 seaward of the former KOA campground sustained major
damage. A segment of Chip Morrison Drive was also destroyed (see Figure 10). While
the granite rock base of the revetment remained in place, the concrete rubble and Florida
limestone boulders along the crest of the granite revetment and comprising an eastern
extension of the revetment were displaced. Storm surge and waves overtopped the
revetment and eroded several vertical feet of the upland property, which destroyed both
the asphalt surface and sub-grade roadbed for approximately 2,600 feet (see Figure 11).




       Photo 31. Dwelling Destroyed, Alligator Point (R210.2)




                                      Page 43 of 51
                                       25



                                       20



                                       15



                                       10



                                        5




                ELEVATION (FT. NAVD)
                                        0




Page 44 of 51
                                        -5



                                       -10
                                         -200          -150           -100            -50       0        50        100                  150       200   250
                                                                                      DISTANCE FROM MONUMENT (FEET)


                                                       BEACH PROFILE                                FRANKLIN
                                                         18JUL05-POST-DENNIS
                                                                                                                                   RANGE: R-210
                                                         19NOV04-PRE-DENNIS               BUREAU OF BEACHES & COASTAL SYSTEMS
                                                                                          FLA. DEPT OF ENVIRONMENTAL PROTECTIONS
                                                                                                                                   BEARING: 205.00

                                        Figure 17. Franklin County before and after beach profile (R210).
                                       25



                                       20



                                       15



                                       10



                                        5




                ELEVATION (FT. NAVD)
                                        0




Page 45 of 51
                                        -5



                                       -10
                                         -200          -150          -100            -50       0        50        100                  150       200   250
                                                                                     DISTANCE FROM MONUMENT (FEET)


                                                       BEACH PROFILE                               FRANKLIN
                                                         18JUL05-POST-DENNIS
                                                                                                                                  RANGE: R-215
                                                         19NOV04-PRE-DENNIS              BUREAU OF BEACHES & COASTAL SYSTEMS
                                                                                         FLA. DEPT OF ENVIRONMENTAL PROTECTIONS
                                                                                                                                  BEARING: 170.00

                                        Figure 18. Franklin County before and after beach profile (R215).
Photo 32. Revetment damaged, road and commercial building destroyed, Alligator
Point (R212.4).




      Photo 33. Dwelling destroyed, Bald Point (R132).


                                  Page 46 of 51
P.     Mashes Sands and Ochlockonee Bay, Wakulla County
Over 210 miles east of the point of landfall of the eye of Hurricane Dennis, Mashes
Sands sustained major beach and dune erosion (condition IV) with storm tides estimated
to be 8 to 10 feet. A one half-mile segment of beach was essentially translated about 50
feet landward revealing a complete roll-over of the beach system into the lagoonal
wetlands. This barrier rollover has exposed a projecting terminus of the former asphalt
road as a headland. All recreation facilities, including parking, picnic shelters, tables, and
the concrete bathhouse were destroyed. The park’s fishing pier lost its interior ramp
section and some railing. In addition, the canal entrance from the public boat ramp has
been substantially clogged with sand. The impact of Dennis was comparable to the
impact of Hurricane Kates (1985) and Agnes (1972).

Throughout the developed area of Mashes Sands, numerous structures were flooded and
sustained interior flood damage. Six dwellings were destroyed or sustained major
structural damage and the county reported another 51 sustained flooding damage.
Another pier was destroyed and all the docks along the northern Ochlockonee Bay
shoreline were destroyed or substantially damaged. Adjacent the Ochlockonee Bay
bridge, a waterfront restaurant over the water sustained significant structural damage.




      Photo 34. Angelo’s Restaurant, Ochlockonee Bay.




                                       Page 47 of 51
Q.     Live Oak Island, Shell Point, Spring Creek, Wakulla Beach,
       Wakulla County
The storm tides of Hurricane Dennis inflicted the most damage to Wakulla County since
Hurricane Kate in 1985. Storm tides of 8 to 10 feet were estimated to have flooded the
area. At the community of St. Marks, on the St. Marks River, the county reported 41
homes and several businesses that were flooded and sustained interior flood damage. At
Wakulla Beach fronting Goose Creek Bay, the five dwellings sustained flooding but no
major damage.

Live Oak Island, severely impacted by Kate, was again substantially flooded. Two major
structures sustained major damage, nine dwellings sustained understructure damage, and
at least eight others were flooded and sustained interior damage.

At Shell Point, 21 major structures sustained major damage, including 13 single-family
dwellings destroyed. At least nine dwellings had understructure damage and the county
reported 178 dwellings sustained flooding damage. In addition, 50 feet of wood retaining
wall was destroyed.

At Spring Creek, four dwellings sustained major structural damage and the county
reported another 40 that sustained flooding damage.

III.   Recovery Recommendations and Management Strategies

A.     Area-wide Strategies and Recommendations
       •   Assist local governments in seeking Federal Emergency Management Agency
           (FEMA) assistance to repair non-federal beach and dune restoration projects.
       •   Conduct assisted-recovery activities consisting of dune restoration and re-
           vegetation, with supplemental beach fill as needed, in areas where a
           significant contiguous length of upland development or valuable natural
           resources are vulnerable to damage from the impact of a moderate storm.
       •   Assist local governments in conducting removal from the active beach and
           dune system miscellaneous storm-generated debris, including construction
           debris, derelict retaining walls and foundation piles of beach access walkways.
       •   Support further sand search studies to locate sufficient upland and offshore
           sand resources to replenish storm-eroded beaches and dunes.
       •   Conduct post-storm coastal monitoring to assess beach erosion impacts and to
           assess beach recovery progress and any additional recovery needs.
       •   Reevaluate Coastal Construction Control Lines. The impact of five hurricanes
           and several tropical storms since establishment of the CCCL’s have rendered
           them inadequate to define the impact zone of a 100-year storm in many areas.




                                      Page 48 of 51
B.    Site-specific Recommendations
Escambia County
      •   Pensacola Beach (R107-R151)
          o Complete the maintenance nourishment of the beach restoration project
             that commenced immediately prior to the impact of Hurricane Dennis.
          o Evaluate an increase in the elevation of the crest of the dune feature of the
             project.

Santa Rosa County
      •   Navarre Beach (R192-R213)
          o Expedite construction of the permitted beach restoration project.
          o Increase the size of the dune feature in the State Park instead of the width
             of the beach.

Okaloosa County
      •   Ft. Walton Beach (R1-R15)
          o Assisted recovery - dune restoration and re-vegetation.
      •   Holiday Isles/Destin/Henderson Beach (R18-R39)
          o Assisted recovery - dune restoration and re-vegetation.
      •   Eastern Destin (R39-R50)
          o Expedite construction of the funded beach restoration project.

Walton County
      •   Western Walton County (R1-R24)
          o Expedite construction of the funded beach restoration project.
      •   Topsail Hill (R24-R41)
          o Assisted recovery - dune restoration and re-vegetation.
      •   Beach Highlands/Dune Allen Beach (R41-R55)
          o Assisted recovery – dune restoration with supplemental beach fill.
          o Expedite planning, design and construction of beach restoration.
      •   Blue Mountain Beach (R55-R63)
          o Assisted recovery – dune restoration with supplemental beach fill.
          o Expedite planning, design and construction of beach restoration.
      •   Gulf Trace / Grayton Beach / Seaside (R67-R82)
          o Assisted recovery – Dune restoration and re-vegetation.
          o Conduct feasibility study of beach restoration.
      •   Seagrove Beach (R82-R97)
          o Assisted recovery – dune restoration with supplemental beach fill.
          o Expedite planning, design and construction of beach restoration.
      •   Seacrest Beach / Dana Beach / Rosemary Beach / Inlet Beach (R105-
          R127)
          o Assisted recovery – dune restoration and re-vegetation.
                                  Page 49 of 51
Bay County
      •   Panama City Beaches (R5-R93)
          o Complete the maintenance nourishment of the beach restoration project
             that commenced after the impact of Hurricane Ivan.
          o Evaluate the sand losses and increase in the volume to repair the damage
             caused by Hurricane Dennis.
      •   St Andrews State Park (R93-R97)
          o Continue inlet sand transfer from the Panama City Harbor maintenance
              project.
          o Expedite construction of the authorized breakwater project adjacent Gator
              Lake.
      •   Mexico Beach (R128-R144)
          o Implement the planned inlet sand bypassing project.
          o Extend and sand tighten the east jetty to the same length as the west jetty
            at Mexico Beach Inlet.

Gulf County
      •   St. Joseph Peninsula State Park (R32-R75)
          o Assisted recovery – dune restoration to close the dune breach at R69.
      •   St. Joseph Peninsula (R75-R105)
          o Landward relocation or rebuilding of damaged or threatened structures.
          o Assisted recovery - dune restoration and re-vegetation.
          o Expedite feasibility study for areas north of Stump Hole, which includes
              wave refraction and sediment transport analysis of Gulf County.
Franklin County
      •   St. George Island (R52-R105)
          o Assisted recovery - dune restoration and re-vegetation.
      •   St. George Island State Park (R105-R149)
          o Assisted recovery - dune restoration and re-vegetation.
      •   Dog Island
          o Landward relocation or rebuilding of damaged or threatened structures.
          o Assisted recovery - dune restoration and re-vegetation.
      •   Alligator Point, Phipps Preserve
          o Natural recovery.
      •   Alligator Point (R195-R209)
          Assisted recovery - dune restoration and re-vegetation.


      •   Alligator Point, Southwest Cape (R210-R218)
          o Landward relocation or rebuilding of damaged or threatened structures.
          o Assisted recovery - dune restoration and re-vegetation.
          o Expedite planning, design and construction of beach restoration.

                                    Page 50 of 51
     •   Lighthouse Point (R218-R224)
         o Natural recovery.
     •   Bald Point (R224 -R239)
         o Natural recovery.

Wakulla County
     •   Mashes Sands
         o Assisted recovery – beach nourishment using sand from the boat canal
           entrance dredging.
     •   Shell Point
         o Assisted recovery – beach nourishment of the public beach areas using
            trucked-in sand.




                                   Page 51 of 51

				
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