Land Use Plan Update Hurricane Mitigation & Reconstruction Plan-1991

: -
Hurricane -Mitigation &Reconstructions Plan
December
1991
New Hanover Counfy,Planning Department;
= _
= =Dexter Hayes; Director
- ::Patrick Lowe, AssistaniDirector
, - , .,
,_
- Staff Planners, -
_ _
- Walter "Pete"Avery _ -
--
--
-
- WandaCoston:-
- Sam Burgess
Chris O'Keefe -
-. - CAMA Intern _
- -
JoAnne Shadroui
-
= Administrative Secretary
- - Phoebe Saavedra
.Graphics Planning Technician
-
Lisa laine Horne.
New Hanover County Board of -Commissioners
,-
I -' E L.."Matt".Mathews,-Oiacrman
'- `Robert G. Greer, Vice Gtairniun
- jonathaBareld -
-
- _
Fred Retchui "
- William H.-Sutton
Planning Board Members -
Earnest Puskas Chairman
Kenneth A.Shankl in,_ illy Chairman -
-. - - -- -
-
-
__ Robert McDonald
- Wesley O: Nixon= -
;
. William Gratliwoi _
- C. Richard-Boisky
.- ,. .
- ' Charles R. Howell_ -
- -
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-
Y_ by North Crrolim Craw! Mamgemeat Program. dinwgh
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0
101
Hurricane Mitigation
& Reconstruction Plan
December 1991
Wilmington - New Hanover County
Land Use Plan Update

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Preface
The Coastal Area Management Act (CAMA), enacted in 1974 by the North Carolina
General Assembly, requires that the 20 coastal counties of the state prepare land use plans.
These plans provide a framework used to guide local leaders as they make decisions for the
protection, preservation, orderly development and management of the North Carolina
coastal area. The original CAMA Land Use Plan for New Hanover County was adopted in
1976. Updates to the plan are required by CAMA on five year intervals This report is part
of the third plan update (1981, 1986 and 1991) performed in conjunction with the
Wilmington -New Hanover Comprehensive Planning Program, initiated in 1974.
InaccordancewithCAMArequireznerns, the landuseplan consists ofthefiollowing elements:
1.) Summary of data collection and analysis;
2.) Existing land use map;
3.) Policy discussion;
4.) Land classification map.
This information plays an important role in the formulation of local development.
regulations, such as zoning ordinances, and it provides input for growth policy decisions.
These reports also provide useful data to the public and private sector in considering
development proposals.
'775ANVIO!
FM
Carolina's Hurricane History Paths

TABLE OF CONTENTS
I.
Purpose and Scope of Study.....................................................................
l
II.
Coastal Storm Characteristics..................................................................2
III.
Coastal Storm Mitigation.........................................................................7
IV.
Evacuation.............................................................................................12
V.
Post Disaster Reconstruction Plan...........................................................18
VI.
Initial Post Disaster Response ....................................... ................19
VII.
Task Force Responsibilities....................................................................20
VIII.
Conclusions and Policy Recommendations.............................................23
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LIST OF TABLES
Table 1
Saffir/Simpson Scale........................................................................................... 4
Table 2
Severity of Risk in Hazard Area.......................................................................... 5
LIST OF FIGURES
Figure 1
Hurricane Strike Percentage Probability.............................................................. 3
Figure 2
Estuarine Shoreline AECs, Ocean Erodible AECs, and Inlet Hazard AECs ......... 6
Figure 3
Storm Surge Contours: Category 5...................................................................... 9
Figure 4
Storm Surge Contours: Category 4.................................................................... 10
Figure 5
North Carolina State Building Code's Basic Design Wind Velocities ................ 13
Figure 6
100 Year Floodplain, Evacuation Routes, and Emergency Shelters ...................14
Figure 7 .
StormEvent Flow Chart.................................................................................... 21

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HURRICANE MITIGATION AND
RECONSTRUCTION PLAN
I. PURPOSE AND SCOPE OF STUDY
This plan focuses on the procedures and policies New Hanover County can utilize to
mitigate the potential for the loss of life and property associated with intense hurricanes and
the orderly reconstruction of public infrastructure after hurricane strikes. In supportofthese
proposed policies and procedures a brief background on coastal characteristics and evacu-
ation will be discussed. This plan is presented under the format required by the N.C. Coastal
Management regulations (T 15:07B .0200) and includes the following items:
A. Composite hazards map including data from the National Flood Insurance Program
(NFIP) maps, Eastern N.C. Hurricane Evacuation Study, flood zones and other
hazardous areas; —
B. Existing land use inventory for those hazardous areas identified in the "Floodplain
Management Plan" of New Hanover County, 1990 prepared by the New Hanover
County Planning Department.
C. Suggested coastal stone mitigation procedures concerning:
1. Effects of high winds, flooding and other factors;
2. Means of discouraging higher density development located in "high energy"
prone areas;
3. Policies dealing with public acquisition of property in hazardous areas; and
4. Policies dealing with timely public evacuation.
1

D. Post -disaster reconstruction plan including:
1.. County emergency plan;
2. Local policies which will direct reconstruction over an extended time period;
3. Formulation of a "recovery task force" to supervise the reconstruction
process;
4. Establishment of a time -table for staging and permitting repairs ofessential
public services; and
5. Development of policies for repair and/or replacement of public infra-
structure, including relocation to less hazardous areas.
II. COASTAL STORM CHARACTERISTICS
The anatomy of a tropical cyclone or hurricane resembles a large, circular column of
clouds with air rotating in a counter -clockwise direction along the storm's periphery to a
concentrated center of low pressure. Winds within these heat sustaining storms may exceed
200 miles per hour near the vortex, although stones of this magnitude are rare.
Atlantic hurricanes typically originate as tropical waves off the west coast of Africa and
in the Caribbean Sea. Hurricanes develop and mature by passing through several stages based
on wind speed characteristics:
Tropical depression: winds of 38 miles per hour or less
Tropical storm: winds between 39 and 73 miles per hour
Hurricane: winds greater than 73 miles per hour
While the hurricane season extends from June through November, most recorded
hurricane activity along the Carolina coast (approximately 90%) has occurred in August,
September and October. New Hanover County has a 6% chance of encountering a direct
strike from a hurricane. (Figure 1) Hurricanes typically have a westward forward movement
of about 12-15 miles per hour. Both the direction and forward speed of the storm can vary
dramatically once entering the Atlantic basin (McElyea et al, 1982).
Predicting the path and travel time of a hurricane can be a difficult and complicated
problem for weather forecasters due to insufficient documentation recorded from previous
storms and unpredictable upper -level wind patterns that steer the storm. In recent years
though, this difficulty has been reduced through the use of forecasting tools such as satellite
imagery, decision arcs and the hurricane watch/warning system. These tools combined with
an enhanced communication network between weather related agencies and local govern-
ment officials, notably Emergency Management, has improved the ability to forecast the
landfall window for storms and greatly diminish the potential for loss of life.
Figure 1 located
page 3.
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K-01
KE
Percentage Probability that a Hurricane (winds exceeding- 73 mph)
. or a Great Hurricane (winds exceeding 125 mph)
will strike a 50-mile segment of the U.S. Coastline in any given year.
5a• 57
y.
(0
• 55 too
54
53
'0
52
5 • 1
4 . .... .
4
4
46
47 45
0 CV
44
CV
• 43
2
42
41 4)
40 coo
39) 39
ro
:3• 38
36 37
0 37
36
3
35
0
34 • 34
13 14 17 19 •
•20
C-A
7 89 10 11 12 21 31
6 22 31
511 1 14 1 16 17 18 23 30 CO
4 9 10
8 6 314 7 6 7 '19
7 69 24 —
2R 0 29 in
• 2
6 2
5 23
29L
3
2
HURRICANES
GREAT HURRICANES
31
Source: McElyea et al, 1982
3

Saffir/Simpson Damage Potential Scale
CATAGORYI
Winds of 74 to 95 miles per hour. Damage primarily to shrubbery, trees, foliage, and unanchored mobile homes. No
real damage to other structures. Some damage to poorly constructed signs. And/or: storm surge 4 to 5 feet above
normal. Low-lying coastal roads inundated, minor pier damage, some small craft in exposed anchorage tom from
moorings.
CATAGORY2
Winds of 96 to 110 miles per hour. Considerable damage to shrubbery and tree foliage; some trees blown down. Major
damage to exposed mobile homes. Extensive damage to poorly constructed signs. Some damage to roofing materials
of buildings; some window and door damage. No major damage to buildings. And/or. storm surge 6 to 8 feet above
normal. Coastal roads and low-lying escape routes inland cut by rising water 2 to 4 hours before arrival of hurricane
center. Considerable damage to piers. Marinas flooded. Small craft in unprotected anchorages torn from moorings.
Evacuation of some shoreline residences and low-lying island areas required.
CATAGORY3
OWinds of 111 to 130 miles per hour. Foliage torn from trees; large trees blown down. Practically all poorly
constructed signs blown down. Some damage to roofing materials of buildings; some window and doordamage. Some
structural damage to small buildings. Mobile homes destroyed. And/or storm surge 9 to 12 feet above normal. Serious
flooding at coast and many smaller structures near coast destroyed; larger structures near coast damaged by battering
waves and floating debris. Low-lying escape routes inland cut by rising water 3 to 5 hours before hurricane center
arrives. Flat terrain 5 feet or less above sea level flooded inland 8 miles or more. Evacuation of low-lying residences
within several blocks or shoreline possibly required.
CATAGORY4
Winds of 131 to 155 miles per hour. Shrubs and trees blown down; all signs down. Extensive damage to
roofing materials, windows and doors. Complete failure of roofs on many small residences. Complete destruction of
mobile homes. And/or: storm surge 13 to 18 feet above normal. Flat terrain 10 feet or less above sea level flooded
inland as faras 6 miles. Major damages to lower floors of structures near shore due to flooding and battering by waves
and floating debris. Low-lying escape routes inland cut by rising water 3 to 5 hours before hurricane center arrives.
Major erosion of beaches. Massive evacuation of all residences within 500 yards of shore possibly required, and of
single -story residences on low ground within 2 miles of shore.
CATAGORYS
Winds greater than 155 miles per hour. Shrubs and trees blown down; considerable damage to roofs of buildings; all
signs down. Very severe and extensive damage to windows and doors. Complete failure of roofs on many residences
and industrial buildings. Extensive shattering of glass in windows and doors. Some complete building failures. Small
Obuildings overturned or blown away. Complete destruction of mobile homes. And/or: stone surge greater than 18 feet
above normal. Majordamage to lower floors of all structures less than 15 feetabove sea level within 500 yards of shore.
Low-lying escape routes inland cut by rising water 3 to 5 hours before hurricane center arrives. Massive evacuation
of residential areas on low ground within 5 to 10,miles of shore possibly required.
Source: McElyea et al, 1982
4

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SEVERITY OF RISK IN HAZARD AREA -
HAZARD AREA
EXPOSURE TO DAMAGING FORCES
Severity
Erosion/
Wave Action/
Flooding
High
Rank
Scour
Battering
Wind
OCEAN ERODIBLE AEC
1
INLET HAZARD AEC
1
ESTAURINE SHORELINE AEC
1
:.
V-ZONE
2
0
WETLAND AEC
2
0
A -ZONE
3
REST OF COMMUNITY
4
Exposure Level:
High - 0 Moderate - 0 Low -
5
Source: McElyea et al, 1982

TO BISGAW
TO CLINTON
To WHITEVILLE
4
Approximate Scale
1" s 3 M leS
CAROLINA BEACH
KURE BEACH
NEW INIIT
NEW HANOVER COUNTY
•\ TO JACMONVILLE X
Y.,
LEGEND
-;° Estuarine Shoreline AECs
Ocean Erodible AECs
• Inlet Hazard AECs
Note: This map shows approximate areas of estuarine
shoreline AECs, ocean erodible AECs, and Inlet
Hazard AECs. This map should not be used for
regulation purposes.

These new forecasting tools are useful in predicting storm landfall tracts but are not
related to storm intensity (Carter,1981). Hurricane intensity can be classified according to
the Saffir/Simpson Scale based on wind speed, storm surge level and barometric atmospheric
pressure. Based on these characteristics, a hurricane can be designated on a scale of 1 to 5
Table 1 located
(Table 1).
page 4.
Hurricane intensity, as based on the Saffir/Simpson Scale, can create other storm
elements that cause fatalities and property damage. These elements include wind and flood
damage, wave action and erosion. New Hanover County is no exception to these forces. In
fact, certain areas along the County's coast will be highly exposed to shoreline erosion and
scouring, wave action/battering and flooding, in addition to wind damage. These areas,
which have a severity rank of one, are Ocean Erodible Areas of Environmental Concern
(AECs) , Inlet AECs and Estuarine Shoreline AECs. These areas are the most critical areas
Table 2 located
for hurricane protection planning with regard to exposure to hurricanes forces. Table 2
page S.
displays these hazard areas and their severity of risk.
Typically, Ocean Erodible AECs start at mean low water and go landward from the
vegetation line a distance equal to 60 times the long term annual erosion rate plus the
shoreline recession projected for a 100 year storm. This width generally varies from 200-400
feet. Inlet Hazard AECs are based on statistical analysis of inlet migration (using a 99.9 %
confidence interval for a ten year period) and such factors as man-made alterations or
unusual hydrologic features. The width of this area may vary from as little as 250 feet for
stable inlets to 4,000 feet in more dynamic areas. This hazard area applies only to existing
inlets , not to past or potential inlets (Owens,1981). The Estuarine Shoreline AEC's cover
all land within 75 feet of the mean high water line. Estuarine lands may be subject to storm
surge and general flooding. Federal Flood Insurance V Zones, which tend to overlap the
above AECs, represent those areas likely to be flooded by the 100 year storm and exposed
Figure 2 located
to scouring/erosive wave action. (See Figure 2:) Detailed maps prepared by the U.S. Corps
page 6.
of Engineers and the N.C. Office of Coastal Management at a scale of 1 "= 400' are available
for review at the County Planning Department.
III. COASTAL STORM MITIGATION
Reducing the risk of fatalities and property damage from hurricanes has always been
the primary goal of local government planners and policymakers. Coastal storm mitigation
falls under the local government's responsibility to protect the public health, safety, and
general welfare (McElyea et al,1982). Because of this inherited responsibility, many local
and state governments have reacted well to coastal stonn problems, especially flooding and
high winds. Local government response has resulted in the delineation of storm prone areas
as they relate to flooding. Additionally, land use controls, such as subdivision and zoning
regulations, coupled with construction standards, greatly help mitigate storm hazards.
The National Flood Insurance Program, created in 1968, was the first nationwide
program to mitigate natural disasters by guiding the location and quality of development in
flood prone areas. The program offers flood insurance to property owners in designated flood
hazard areas. In return, local and state governments enact and enforce comprehensive
floodplain management measures in order to protect lives and new construction from
flooding (McElyea et al,1982).
7

Most of New Hanover County is vulnerable to hurricane -induced flooding. A major
modeling effort of potential flooding levels within the County and the balance of eastern
North Carolina by the N.C. Division of Emergency Management, the Federal Emergency
Management Agency and the U.S. Army Corps of Engineers has produced "The Eastern
North Carolina Evacuation Study". A primary product of this collaborative study is the Sea,
Lake and Overland Surges from Hurricanes (SLOSH) model. Using this model, various
storm surge scenarios are depicted based on the Saffir-Simpson Scale, storm movement/
direction, forward motion of the storm and the point of landfall.
For any given storm category, based on the Saffrr-Simpson Scale, flooding would
typically occur with more intensity from northwest bound hurricanes than from hurricanes
with other directional headings. Using the model for New Hanover County, it is projected
that the County would be subjected to a 13 foot storm surge based on a category 4 hurricane
moving northwest with a forward motion of 12 miles per hour. A storm surge exceeding 17
feet could be expected with a category 5 storm moving northwest with the same forward
speed of 12 miles per hour (Figures 3 and4). A full report describing these various hurricane
scenarios is available for review at the County Department of Emergency Management.
In New Hanover County, approximately 17,300 acres of land are located in the 100
year floodplain. This land includes swamps, but not marshlands or large waterbodies.
Approximately 1,900 structures are located within the County's floodplain, based on an
examination of aerial photos of the County (March 1990; scale I" = 400', F000dplain
Management Plan,1990).
Land use controls, such as subdivision regulations, can be utilized to reduce the risk of
flood damages and erosion. In New Hanover County, subdivision regulations currently
require several elements of hurricane hazard information for new developments. Site plans
require that 100 year floodplains, topography, watercourses and other drainage features be
displayed. Also, developers of projects located on barrier islands must submit an additional
map displaying/describing the hurricane evacuation potential for the development. This
description must include estimated road capacities, bridges and low elevation points of roads
as well as estimates of mobilization, travel, and queuing delay times for safe evacuation. The
Subdivision regulations are most effective at reducing flood damage when used in conjunc-
tion with zoning and construction codes.
Zoning is a very common device to manage land development. It is used to control the
use of land and structures via setbacks, density and height limits, etc. Development in New
Hanover County is restricted in hurricane hazard areas by the Zoning Ordinance. This
Ordinance deals with several provisions that helps mitigate potential hazards associated with
hurricanes. Key provisions include the Conservation Overlay District, non -conforming
structures and performance and high density residential development controls.
The Conservation Overlay District encompasses the entire unincorporated County with
the exception of Pleasure Island. This district protects certain valuable natural resources. A
number of these resources are hazard oriented areas such as swamp forest, natural ponds,
marshes and maritime shrub thickets. The protection measures include varying setbacks,
drainage restrictions with storm waterretention, and preservation of 50-100% of the resource
in its natural state. For example, residential or commercial structures would be prohibited
Figure 3 located
page 9.
Figure 4 located
page 10.

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STORM SURGE CONTOURS: CATEGORY 5
NW - CAT 5 - 12 MPH
.... . ....... ........ —
_4 elJ K f f�
5
r,L/ZZ,8 /
9 / 7
5
// 4 **� ' -S
New Hanover County
7
6
5
4
3
-3
�2
78OW 770W 33*N 76*W 75OW 340N 74OW 35*N 360N 370N 74
Source: Eastern North Carolina Hurricane Evacuation Study, 1987
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STORM SURGE CONTOURS: CATEGORY 4
Source: Eastern North Carolina Hurricane Evacuation Study, 1987

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Figure 5 located
page 13.
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from being constructed along the shoreline due to strict setbacks imposed by the conservation
overlay requirements. Setbacks range from 25 to 100 feet.
Non -conforming uses/structures involve the use of a building or land which does not
conform to the regulations of the zoning ordinance for the district in which it is located, either
at the effective date of the ordinance or as a result ofsubsequent amendments. Generally, non-
conforming structures may not be increased in area occupied and restrictions such as lot or
yard requirements may not be reduced. If a non -conforming structure is totally or partially
destroyed, it may be replaced provided notice of intent is provided within six months and a
building permit is issued within twelve months. Reconstruction must meet current building
codes and zoning requirements. Finally, if a non -conforming use is discontinued for more
than 180 days, then the property must be used only for conforming purposes from that point
on:
Performance residential developments allow for flexible lot lines and setbacks,
facilitating a site plan layout that avoids hazardous areas as opposed to the "cookie cutter"
method of conventional subdivisions. Maximum density is based on a net tract acreage after
subtracting all natural ponds, lakes, rivers, marshes and class IV soils from the gross acreage.
Drainage regulations would also be required. High density residential developments like
their cousin "Performance Developments" allow for flexible lot lines and setbacks, thereby
creating a site plan layout around environmentally sensitive and hazard areas. Maximum
density is based on site capacity standards, subtracting from the gross acreage such elements
as water bodies(tidally or non -tidally influenced) and open space (flood boundaries,
waterfront shorelines, conservation). Drainage regulations would be required also.
Construction codes have also been widely utilized by local and state governments to
reduce the hazard of flooding and intense winds by creating standards for flood -proofing,
elevation and wind resistance. For example, Wrightsville Beach adopted a code in the mid
1950's requiring -all structures to be elevated on pilings eight feet above mean high water.
Wind resistance standards appear in most state and local codes. The North Carolina State
Building Code establishes "basic design wind velocities" of 110 to 120 miles per hour for
its oceanfront counties (McElyea et al, 1982), (Figure 5). New Hanover County uses the
State Building Code forall of theircommercial andresidential inspections fornew structures.
The preservation of floodprone areas as open space in New Hanover County is the most
effective means of mitigating storm damage. Preservation can be achieved through public
acquisition, restrictive regulations and deed restrictions. Acquisition and relocation of
existing structures by the County would be ideal but impractical due to the cost unless some
Federal incentive is provided (Floodplain Management P1an,1990).
The purchase of high risk areas for open space and recreation is one of the best
mitigating measures a local government can use -The State has control over the Fort Fisher/
N.C. Aquarium beaches and it is purchasing Masonboro Island to become part of the
Estuarine Research Reserve Program.
11

IV. EVACUATION
Timely public evacuation for the beaches of New Hanover County (Wrightsville
Beach, Carolina Beach and Figure Eight Island) is largely dependent upon the issuance of
a hurricane waming by the National Weather Service and the efficient utilization of
evacuation routes and shelters (Figure 6). Because the hurricane warning is usually given
at least 24 hours in advance of the storm center's arrival, calculated evacuation times can be
derived based on the following components.
Evacuation time is composed of two separate components, clearance time and pre -
landfall hazards time. Clearance time is defined as the time necessary for the relocation of
all vulnerable evacuees to a safe area once the official evacuation order is issued. Clearance
time can be broken down into three subcomponents: mobilization time, travel time and
queing delay time.
(a) Mobilization time is that period between the issuance of the evacuation order
and the departure of the vehicles. It represents the time needed for evacuees to
learn of the evacuation order, pack some belongings and leave. Three hours per
household is a typical time period used in other studies and corresponds with
preliminary survey results of residents and tourists during August and Septem-
ber, 1983, on Wrightsville, Carolina and Kure Beaches.
(b) Travel time is the period necessary for the vehicles to travel the length of the
evacuation route at an anticipated speed, assuming no queing delays.
(c) Queing delay time is the amount of time spent by vehicles in traffic jams when
the capacity of the evacuation routes are exceeded by the number of vehicles
entering those routes. A bottleneck would occur, forinstance, where fourlanes
converge into a two lane bridge.
The roadway capacity factors used to determine evacuation times for the area were
obtained from a study in Currituck County (Collins,1983). Approximately 1575 vehicles
per hour (vph) for two lane roads and 3222 vph for four lane roads will be used. Capacity
levels would increase for roads with adequate shoulders, parking and turning lanes. The
elements mentioned above take into account the following adjustments: common roadway
capacity standards for engineers purposes, a 35% reduction in vehicular capacity due to
adverse weather, a 15% reduction for stalled/wrecked cars and a 10% reduction for
emergency vehicle use. In order for these capacity factors to have a large degree of validity,
evacuation traffic must be strictly controlled using law enforcement personnel.
Pre -landfall hazards time represents the period of time between when evacuation from
the vulnerable area first becomes extremely difficult due to either gale force winds or stone
surges that inundate evacuation routes and when the eye of the hurricane reaches the coast.
A typical value for a severe hurricane registering a 'T' on the Saffir/Simpson scale would
equate to four hours. This amount of time plus clearance time equals evacuation time.
Figure 6 located
page 14.
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North Carolina State Building Code's
Basic Design Wind Velocities (in mph)
80
80 10o C
90 I I � 1
91
120
Source: North Carolina Building Code Council, 1981, Volume I - General Construction
13

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EVACUATION TIMES
An analysis of the components of evacuation time is shown below for Wrightsville
Beach, the area south of Snow's Cut (Pleasure Island) and Figure Eight Island. Household
and motel/condominium units are based on 1990 data derived from their respective
communities and the Figure Eight Homeowners Association. While other areas of hazard
exist in the County such as sounds, creeks and rivers (estuarine shoreline and 100 year
floodplain), evacuation from these areas are considered to be adequate due to the short
distance to the major evacuation mutes and low concentrations of populations served by
these mutes.
The analysis utilizes methods and assumptions drawn from work developed by the
State Office of Coastal Management (McElyea. et al 1983), the Sea Grant Program atNCSU
(Stone,1983) and an analysis prepared for Currituck County (Collins,1983). The analysis
assumes the following "worst case" scenario: A catastrophic hurricane measuring 5 on the
Saffir/Simpson Scale has dramatically shifted direction and is heading toward the southeast
coastof North Carolina. The eye of the hurricane is expected to reach landfall within 24 hours.
A Hurricane Warning has been issued by the National Weather Service and the County's
local governments have issued evacuation orders through law enforcement and the media.
Based on the 1990 population of the beaches within New Hanover County and the number
of tourist on the coast, can the islands of Wrightsville Beach, Pleasure Island and Figure
Eight Island (Carolina, Kure and Fort Fisher) be evacuated in a safe and timely manner?
The analysis displayed below is considered conservative due to certain assumptions
concerning traffic flow. Due to the severity of the storm, up to 30% of the short-term renters
and residents would most likely leave before the evacuation orderis given (Stone, 1983).This
30% deduction is incorporated in the calculations below.
Wrightsville Beach
Total Evacuation Time = Total Clearance Time + Pre -Landfall Hazard Time
= 6.53 hours + 4 hours
=10.53 hours
The total evacuation time of 11 hours (rounded) indicates that Wrightsville Beach
could be safely evacuated if the evacuation order is concurrent with a Hurricane Warning.
This conservative estimate also includes the following variables:
Total Clearance Time = Mobilization Time + Travel Time + Queuing Delay Time
= 3 hours + .25 hrs1I + 3.28 hrsl2
15

1. Travel Time: Under free flow conditions, a car should be able to travel from any point
on Wrightsville Beach to the mainland in a maximum of 15 minutes.
2. Queuing Delay, Time: Queuing delays will result from vehicles coming from
residential streets onto Highways 74 and 76 (Waynick Blvd., Lumina Ave., and
Causeway Dr.). It is assumed that the traffic coming off the drawbridge onto the
mainland will be controlled to prevent back-up. Calculations are as follows:
• Assume that a total of 3273 households and motel/condominiums require evacuation.
Each has an average of 1.6 vehicles per household for a total of 5,237 vehicles.
• Assume also that one half (2619) of the vehicles will evacuate from the southern end
of the beach and one half (2618) from the northern beach evacuate at the same time along
a two lane road. Since evacuation will take place on two separate, two lane stretches of road
at the same time, maximum queuing delay time would be calculated using the larger of the
two vehicle figures determined above.
Queuing Delay Time = 2619 vehicles
1575 vph capacity
Queuing Delay Time = 1.66 hours
• Assume that all vehicles (5237) must travel on a four lane road to the mainland. The
maximun queuing delay time would be:
Queuing Delay Time = 5237 vehicles
3232 vph capacity
Queuing Delay Time =1.62 hours
• The Wrightsville Beach drawbridge, according to the Department of Transportation,
will not be opened during high winds and therefore, would not be a significant delay in traffic.
Total maximum queuing delay time = 1.66 hrs. + 1.62 = 3.28 hours
Pleasure Island (Carolina Beach,Kure Beach, Fort Fisher)
Total Evacuation Time = Total Clearance Time + Pre -Landfall Hazards Time
6.65 !tours + 4 hours
= 10.65 hours
The total evacuation time of 10.65 hours indicates that this area of the County could
be safely evacuated if evacuation is ordered concurrent with a Hurricane Warning.
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16

Total Clearance Time = Mobilization Time + Travel Time+ Queuing Delay Time
3 hours + .5 hrsll + 3.15 hrs12
= 6.65 hours
1. Travel Time: Under free flow traffic conditions, a vehicle should be able to travel from
any point in the County south of Pleasure Island to north of Snow's Cut within 30
minutes.
2. Queuing Delay Time: Queuing delays will result from vehicles coming from
residential streets onto Carolina Beach Road (highway421 south). Computations are
addressed below:
• Assume that a total of 4195 households and motel/condominium groups will require
evacuation. Each has an average of 1.6 vehicles per household, for a total of 6712 vehicles.
• Assume that one quarter 1678 of the vehicles will evacuate from the area south of
Carolina Beach north to Carolina Beach, using the two lane section of US Highway 421.
Queuing Delay Time = 1678 vehicles
1575 vph capacity
Queuing Delay Time = 1.07 hours
• Assume that all vehicles 6712 will evacuate north from Carolina Beach to north of
Snow's Cut, using the four lane section of US Highway 421.
Queuing Delay Time = 6712 vehicles
3232 vph capacity
Queuing Delay Tme = 2.08 hours
Total maximum queuing delay time =1.07 + 2.08 hours = 3.15 hours
Figure Eight Island
Total Evacuation Time = Total Clearance Time + Pre -Landfall Hazard Time
= 3.65 hours + 4 hours
= 7.65 hours
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The total evacuation time of 7.65 hours indicates that Figure Eight Island would be
safely evacuated if evacuation is ordered concurrent with a 12 hour Hurricane Warning.
Total Clearance Time = Mobilization Time + Travel Time 11 + Queuing Delay Time 12
3.65 hours = 3 hours + .25 hours .40 hours
1. Travel Time: Under free flow traffic conditions , a car should be able to travel from
either end of Figure Eight Island to the mainland in 15 minutes.
2. Queuing Delay Time: Queuing delays will result from vehicles coming from
residences onto Beach Road and then onto Bridge Road. Calculations are given
below:
• Assume that a total of 212 households require evacuation. Each has an average of 2
vehicles per household for a total of 424 vehicles.
• Assume that one half of the vehicles (212) will evacuate simultaneously from the
northern end. For these two-lane stretches of road, maximum queuing delay time would be:
Queuing Delay Time = 212 vehicles
1575 vph capacity
Queuing Delay Time = .13 hours
• Assume that all vehicles must travel on the two-lane Bridge Road to the mainland.
This maximum queuing delay time would be:
Queuing Delay Time = 424 vehicles
1575 vph capacity
Queuing Delay Time - _ .27 hours
Total Maximum Queuing = .13 hours + .27 hours Delay Time = .40 hours
V. POST DISASTER RECONSTRUCTION PLAN
The following information presents proposed policies and procedures that may be
implemented in New Hanover County after a massive and damaging hurricane strike (a
category4 storm on the Safr-Simpson scale). If adopted, these policies would compliment
the adopted Hurricane Evacuation Plan supplied by the Department of Emergency
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Management and would be considered for incorporation into the Wilmington -New Hanover
County Land -Use Plan Update. The primary thrust of these proposed policies is to permit
the County to rebuild at a smooth and controlled pace ensuring public safety and protecting
lives and property.
VI. INITIAL POST DISASTER RESPONSE
Initially, it should be mentioned that immediate cleanup and removal of debris from
public roads is the responsibility of the North Carolina Department of Transportation. In
other situations, the Assistant County Manager is responsible for the overall supervision of
cleanup and disposal of County debris resulting from a stone.
The responsibility for directing reconstruction within New Hanover County after a
damaging storm should rest with a "Recovery Task Force". This committee should reflect
a broad representation of community interests. At a minimum, this committee should be
composed of the following individuals:
1. Two elected officials (County Commissioners and/or City Council)
2. County Manager or his designee
3. Emergency Management Director
4. County Engineer
5. County Health Director
6. Planning Director
7. Zoning Administrator
8. Chief building inspector
9. Property Management Director
10. County Sheriff
11. County Fire Marshal
12. One representative from either the realty or construction community
(preferably the construction f eld)
13. Representative from Southern Bell
14. Representative from C.P.& L.
15. Representative from the City of Wilmington
Members of this task force shall be appointed annually by the Board of County
Commissioners.
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VII. TASK FORCE RESPONSIBILITIES
The task force shall be responsible for advising the Board of Commissioners on a
diverse range of post -storm reconstruction issues. A principle function of the task force is
to receive and assess damage reports from the "local damage assessment team" or "control
group" as defined in the Hurricane Evacuation Plan (Rev.1990) prepared by the Department
of Emergency Management.
Other responsibilities of the recovery task force would include:
1. Reviewing the nature of the damages, identifying and evaluating alternative
program approaches for repairs and reconstruction and formulating recommenda-
tions for handling County recovery.
2. Recommending possible rezoning changes in areas of severe damage to accommo-
date rebuilding
3. Setting a definitive, yet flexible calendar of reconstruction goals in conjunction
with other local officials.
4. Initiating requests for repairs and upgrading critical utilities.
5. Recommending the expiration or extension of the moratorium on structural repairs.
6. Recommending the lifting or extension of the moratorium on new development.
7. Initiating negotiations for relocations and acquisitions of property.
8. Participating in federal hazard mitigation planning.
The task force could also recommend changes in zoning, subdivision and mobile home
park/travel trailer regulations, building codes or any other regulations which it deems
necessary or advisable to prevent a recurrence of coastal storm damage.
As mentioned, the local damage assessment team is responsible for locating and
identifying structures that have been damaged by a hurricane. Based on their assessment, this
team can advise and identify for the Inspections Director those structures which have been
destroyed, received major damage (foundation, roof, other structural elements) or minor
damage (minimal repairs to windows, doors, floors or other minorstructural elements). The
Department of Inspections can then verify what has been done by the assessment team and
classify each structure accordingly. Additional out of town building inspectors may be
required depending on storm severity.
A building moratorium shall be declared in effect upon the occurrence of one or more
of the following elements:
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* Duration of Moratorium. May be cancelled or extended by the Reconstruction Task Force or by
resolution by Board of Commisioners.
OEmergency repairs can be done anytime - examples: minor interior repairs and repairs necessary to
prevent injury, loss of life or imminent collapse.
Source: Nag's Head Planning Department, 1988
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Figure 7 located
page 21.
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1. The County is directly hit by a category 4 storm or greater based on the Saffir-
Simpson scale as determined by the National Weather Service.
2. The County is declared a disaster area by either the Governor of North Carolina or
the President of the United States.
3. Several hundred or more structures have received major damage or been destroyed
as determined by the Inspections Department.
4. Upon determination by the local damage assessment team chairman in accordance
with N.C.G.S.14-288 as amended, an initial building moratorium may be declared
for the protection of lives, safety and property or due to the inability of the county
to maintain acceptable levels of public order and services. -
Once a building moratorium has been declared, the recovery task force will be
activated. The initial building moratorium shall be in effect for at least two days (See Figure
7). Building permits will not be issued during this time.
Building permits will not be issued within thirty working days following the termina-
tion of the initial moratorium for the replacement of any structure which has been destroyed.
The replacement of any structure shall be subject to meeting all the requirements of the
County's zoning regulations and, of course, all applicable building codes.
For structures that have received major structural damage from a stone event, a seven
working day waiting period will be required following the expiration of the initial
moratorium. All necessary repairs shall meet applicable zoning and building code require-
ments prior to the issuance of a building permit.
Permits forthe repairof structures thathave received only minordamage may be issued
following the expiration of the initial moratorium. All minor repairs will be in accordance
with applicable zoning and building code regulations.
Building permits issued prior to a massive stone event shall be void and not reissued
for at least thirty (30) working days following the expiration of the initial moratorium. This
period of time may be reduced on a case -by -case basis if in the opinion of the Director of
Inspections, sufficient staff is available to provide inspections of the structures once
construction resumes. Revoked building permit applications shall be reissued at no charge.
Preliminary site plans submitted to the County Planning Department prior to the storm
event which have not received approval by the Planning Board shall not be reviewed for a
period of thirty (30) days following the expiration of the initial moratorium. Scheduled
review periods shall be established after the moratorium is lifted.
This thirty (30) day moratorium shall also apply to any submittal of final plats, minor
subdivisions, mobile home park/travel trailer plans, rezonings, special use permits, and
conditional use applications. Submittal dates shall be adjusted accordingly to reflect the
moratorium termination.
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All moratoriums may be cancelled -or extended by the Recovery Task Force or
resolution by the Board of County Commissioners.
Emergency repairs may be permissible to prevent injury, loss of life or imminent
structural collapse. Minor interior repairs may also take place to prevent additional damage
from wind and water.
VIII. CONCLUSION AND POLICY
RECOMMENDATIONS
Based on Hurricane Hugo in 1989 and other documented literature, it has been realized
that any intense hurricane event of 4 or 5 on the Saffir/Simpson Scale would create a
significant amount of property damage in New Hanover County resulting in recovery
operations that could take years. Due to the potential for such naturally occurring events, the
following policies are suggested for inclusion in the Wilmington -New Hanover County
Land -Use -Plan Update to help insure the orderly reconstruction of public property
POLICY: Immediate clean-up and removal of debris from public roads is the
responsibility of the North Carolina Department of Transportation. Public expenditure of
funds for the repair or reconstruction of any private road or vehicular easement which is
damaged or destroyed as a result of an intense stone event shall not occur, except in
conjunction with the repair of the County's sewer. All other private roads will be the
responsibility of the individual landowners.
POLICY: The Assistant County Manager shall be responsible for the overall
supervision of clean-up and disposal of County debris resulting from an intense storm event.
POLICY: The responsibility for directing reconstruction within New Hanover
County after a damaging stone shall be the Recovery Task Force. This task force shall be
responsible for advising the Board of County Commissioners on a diverse range of post -
storm issues.
POLICY: A building moratorium of no less than thirty (30) working days following
the initial two (2) day moratorium shall not occur unless authorized or extended by the
Recovery Task Force or resolution by the Board of County Commissioners.
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POLICY: Following a storm event, the County will take advantage of opportunities
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to acquire or purchase land located in storm hazard areas which are rendered unbuildable. The
property should satisfy objectives including, but not limited to the conservation of open
space, scenic areas and provision of public water access.
After a major storm event, there are numerous federal and state programs that are
available to the County to aid in disaster relief, recovery and reconstruction. These programs
canprovide assistance or funds through local government to individuals, businesses, families
and non-profit associations. Some of these programs can only be implemented upon
declaration of a major disaster by the President of the United States. Other programs can be
made available independently of a Presidential Declaration of a major disaster emergency.
POLICY:. It shall be a policy of the County to retain on a seasonal basis an Assistance
Facilitator/Consultant who, as directed by the County Manager, will be responsible for:
1. Determining the types of assistance available to the county and the type of
assistance most needed,
2. Assisting in the coordination of federal disaster recovery effort,
O3.
Coordinating federal and state programs of assistance,
4. Informing the County citizenry of types of assistance programs available,
5. Recommending to the Recovery Task Force and Board of Commissioners
programs which are available and then acting as facilitator in securing those
programs.
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REFERENCES
1. Carter, T.M. 1981, "Probability of HurricanelTropical Storm Conditions: A
Users Guide For Local Decision Makers". USDOC/NCA-NWS.
2 McElyea, W.D., D.J. Bfrowers, and D.R. Godschalk, 1982, "Before The
Storm: Managing Development to Reduce Hurricane Damages," Center for
Urban and Regional Studies, UNC-Chapel Hill.
3. Stone, J.R., 1983, "Hurricane Emergency Planning: Estimating Evacuation
Times for Non -Metropolitan Communities," Working Paper 83-2, Sea Grant
Program, NCSU.
4. Collins, W.E.,1983, "Carrying Capacity Methodolgy," Nags Head, NC.
5. Nags Head Planning Department, 1988, " Hurricane & Storm Mitigation and
Reconstruction Plan," Town of Nags Head, Nags Head, N.C.
6. New Hanover County Planning Department, 1990, "Floodplain Management
OPlan,"
New Hanover County, Wilmington, N.C.
7. New Hanover County Department of Emergency Management, 1990, "New
Hanover County Evacuation Plan," New Hanover County, Wilmington,
N.C.
8. U.S. Army Corps of Engineers, Federal Emergency Management Agency,
N.C.-Division Emergency, 1987, "Eastern N.C. Hurricane Evacuation
Study," US COE, Wilmington District.
9. Carter, T.M., 1981, "Probability of HurricanelTropical Storm Conditions: A
Users Guide for Local Decision Makers," USDOC/NCA-NWS.
10. Owens, D.. 1981, "The Management of Oceanfront Development in North
Carolina," paper presented at the 7th annual Conference of The Coastal
Society, October 11-14, 1981, Galveston, Texas.
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