O86-16ORDINANCE NO.
AN ORDINANCE OF THE CITY COUNCIL OF THE
CITY OF BOYNTON BEACH, FLORIDA, ADOPTING
A COASTAL CONSTRUCTION CODE; SETTING FORTH
THE PURPOSE AND SCOPE THEREOF; PROVIDING
REQUIREMENTS FOR EXISTING STRUCTURES;
SETTING FORTH PROVISIONS FOR THE CONSTRUCTION
SEAWARD OF THE ~IN HIGH WATER LINE AND
REQUIREMENTS FOR THE APPLICATION FOR BUILDING
PE~ITS; PROVIDING DEFINITIONS; PROVIDING
COASTAL CONSTRUCTION REQUIREMENTS FOR MAJOR
STRUCTURES, INCLUDING FOUNDATIONS, UNDER-
STRUCTURES, BUILDING AND FLOOR ELEVATIONS,
EROSION AND DESIGN GRADE, WAVE PORCE DESIGN,
HYDROSTATIC LOADS, HYDRODYNAMIC LOADS, AND
GENERAL DESIGN CONDITIONS; PROVIDING
STRUCTUR~ REQUIREMENTS FOR NONHABITABLE
MAJOR STRUCTURES; PROVIDING STRUCTURAL
REQUIREMENTS FOR MINOR STRUCTURES; SETTING
FORTH REQUIREMENTS FOR THE LOCATION OF
CONSTRUCTION; SETTING FORTH PROVISIONS
CONCERNING PUBLIC ACCESS; PROVIDING
REFERENCES FOR DESIGN PE ~RAMETERS AND
METHODOLOGIES; PROVIDING A CONFLICTS CLAUSE,
A SEVERABILiTY CLAUSE AND AN EFFECTIVE DATE;
AND FOR OTHER PURPOSES.
NOW, THEREFORE, BE IT ORDAINED BY THE CITY COUNCIL
OF THE CITY OF BOYNTON BEACH, FLORIDA, that:
Section i: There is hereby created the following
Coastal Construction Code for the City of Boynton Beach, Florida,
which shall read as follows:
Section 10i - Title
The provisions contained herein shall constitute
the Coastal Construction~C.ode'-,_f.or~cons~truc~ion
within the coastal building zone of the City of
Boynton Beach, Florida and shall be referred to
as the "Coastal Construction Code."
Section 102 - Purpose
The purpose of the Coastal Construction Code is
Go provide minimum standards for the design and
construction of buildings and structures to reduce
the harmful effects of hurricanes and other natural
disasters occurring to the City of Boynton Beach,
Florida. These standards are intended to specifi-
cally address design features which affect the'
structural stability of the beach, dunes, and
topography of adjacent properties. The Coastal
Construction Code is site specific to the coastal
building zone and coastal barrier islands as
defined herein and is not applicable to other
locations. In the event of a conflict with this
chapter and other chapters of this code, the
requirements resulting in the more restrictive
design shall apply. No provisions in this chapter
shall be construed to permit any construction in
any area prohibited by local city, county or state
regulation.
Section 103 Scooe
The requirements of this Coastal Construction
Code shall apply to the following types of
construction in the coastal building zone
within the City of BoyntonBeach, Florida.
(a) The new construciton of, or improvement
to major structures, ~onhabitable major structures,
and minor structures as defined herein.
(b) Construction which would change or alter
the character of the shoreline (e.g. excavation,
grading, paving). The Coastal Construction Code
does not apply to minor work in the nature of
normal beach cleaning or debris removal.
Section 104 - Existing Structures
The requirements of this Chapter shall not apply
to existing structures, structures under con-
struction, or structures for which a valid and
unexpired municipal or county building permit
was issued prior to the adoption of the Coastal
Construction Code.
Section 105 - Multi-ZOne Structures
For structures located partially in the coastal
building zone, the requirements of the Coastal
Construction Code shall apply to the entire
structure.
Section 106 - Construction Seaward of Mean High Water
Structures or construction extending seaward of
the mean high water line which are required by
Section 161,041, Florida Statutes, (e.g., groins,
jetties, moles, breakwaters, seawalls, revetments,
beach nourishment, inlet dredging, etc.), are
specifically exempt from the provisions of this
chapter. In addition, the Coastal Construction
Code does not apply to piers, pipelines, or
outfalls which are regulated pUrsuant'to the
provisions of Section 161.053, Florida Statutes.
Section 107 - Applications for Permits
Applications for building permits for all
construction in the coastal building zone and
on coastal barrier islands, if not of normal
or usual design as determined by the Building
Official, shall be certified by an architect or
professional engineer registered in the State of
Florida. Such certification shall state that the
design plans and specifications for the construction
are in compliance with the criteria established by
this Coastal Construction Code~.
Section 108 - Definitions
The-following terms are defined for general use in
the Coastal ConstrUction Code:
(a) "Beach" means the zone of unconsolidated material
that extends landward from the mean low water line
to the place where there is marked change in material
or physiographic form, or to the line of permanent
vegetations, Usually the effective limit of storm
waves. "Beach is alternatively termed "shore".
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(b) "Breakaway wall" or "Frangible Wall"
means a partition independent of support-
ing structural members that will withstand
design wind forces, but will fail under
hydrostatic, wave, and run~.up forces
associated with the design storm surge.
Under such conditions, the wall shall
fail in a manner such that it breaks up
into components that will minimize the
potential fOr damage to life or adjacent
property.
(c) "Building Support Structure" means
any structure whch supports floor, wall
or column loads, and tr.ansmits them to the
foundation. The term shall include beams,
grade beams, or joists, and includes the
lowest horizontal structural member exclu-
sive of piles, columns, or footings.
(d) "Coastal Building Zone" means the
land area from the seasonal high-water
line landward to a line One Thousand Five
Hundred Feet (1500') landward from the
coastal construction control line as
established pursuant to Section 161.053,
Florida Statutes.
(e) "Column Action" means the potential
elastic instability in piles or columns
resulting in axial or lateral bending
of the member due to compressive stress.
(f) Construction" means the carrying out
of any building, clearing, filling, or
excavation or the making of any material
changes in the size or use of any structure
or the appearance of any land. When appro-
priate to the context, "construction"
refers to the act of construction or the
result of construction.
(g) "Dune" means a mound or ridge of loose
sediments, usually sand-sized, lying land-
ward of the beach, and deposited by natural
or artificial menns.
(h) "Major Structure" includes but is not
limited to residential buildings including
mobile homes, commercial, institutional,
industrial, and other construction having
the potential for substantial impact on
coastal zones.
(i) "Mean High Water Line" means the inter-
section of the tidal plane of mean high water
with the shore. Mean high water is the
average height of high waters over a 19-
year period. (See Section 17o.27(15),
Florida Statutes).
(j) "Minor Structure" includes but is not
limited to pile-supported, elevated dune and
beach walkover structures; beach access ramps
and walkways; stairways; pile-supported elevated
viewing platforms, gazebos, and boardwalks~ life-
guard support stands; public and private bath-
houses; sidewalks, driveways, parking areas,
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shuffleboard courts, tennis courts, handball
courts, racquetball courts, and other uncovered
paved areas; earth retaining walls; sand fences,
privacy fences, ornamental walls, ornamental
garden structures, aviaries, and other ornamental
construction. It shall be a characteristic of
minor structures that they are considered to be
expendable under design wind, wave, and storm
forces.
(1) "Nonhabitable Major Structure" includes but
is not limited to swimming pools, parking garages;
pipelines; piers; canals, lakes, ditches,
drainage structures, and other water retention
structures; water and sewage treatment plants;
electrical power plants, transmission and distri-
bution lines, transformer pads, vaults, and sub-
stations; roads, bridges, streets, and highways;
underground storage tanks; communications build-
ings and towers; flagpoles and signs over 15
feet in heights.
(m) "NGVD" means National Geodetic Vertical
Datum - a geodetic datum established by the
National Ocean Service and frequently referred
to as the 1929 Mean Sea Level Datum.
Section 109 - COASTAL CONSTRUCTION REQUIREMENTS
section 109.1 - General
Construction within the coastal building zone
and on coastal barrier islands shall meet the
requirements of this chapter. All structures
shall be designed so as to minimize damage to
life, property, and the natural evironment.
Assistance in determining the design parameters
to minimize such damage may be found in the
reference documents listed in Section 109.7.
Section 109.2 - Structural Requirements for
Major StruCtures
(a) FoUndations
Ail major structures shall be anchored to their
foundation in such a manner as to prevent
flotation, collapse, or lateral displace-
ment.
Foundation design and construction shall con-
sider all anticipated loads resulting from
design storm conditions, includinq wave, hydro-
dynamic, hydrostatic, and wind loads acting
simultaneously with dead loads. Erosion compu-
tations for foundation design shall account
for all vertical and lateral erosion and scour-
producing forces, including localized scour due
to the presence of structural components.
Pile Foundations - shall be required for build-
ings located in Federal Emer-
gency Management Agency Flood
Insurance Rate Map "V"
(velocity) zones where
impacted by wave action.
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(A) Pile dimensions, spacing and embedment shall
be designed consistent with the requirements
of the site, taking into account all vertical,
lateral, erosion and scour-producing forces.
(B) Piles shall be drived to a penetration which
achieves adequate bearing capacity taking
into consideration the anticipated loss of
soil above the design grade.
(C) In addition to the normal foundation analysis,
the pile foundation analysis shall consider
piles in column action, where appropriate,
from the bottom of the support structure to
the design grade.
(D) Consideration shall also be given to the
degree of exposure to wave attack and the
resulting impact loads on lateral or diagonal
bracing between piles.
2. Monolithic Foundations - may be permitted in
Federal Emergency Agency
Flood Insurance Rate Map
"a" or "B" zones or in
locations not impacted
by wave action.
(A) Monolitic foundations may be used if soil
conditions permit and if located at an
elevation which minimizes their effect on the
beach and adjacent properties. Due consid-
eration shall be given to their vulnerability
to erosion under design storm conditions.
(B) In the event that a monolithic foundation is
usedr the maximum elevation of the top of the
slab is to be below the design scour depth
(see Chapter 5.28, Shore Protection Manual,
U. S. Army Corps of Engineers, 4th edition,
1984) unless positive methods are provided
to prevent scour.
(C) Other types of spread footings such as running
footers or pads may be permitted when positive
methods are provided to prevent scour.
(b) Understructures
No substantial walls or partitions shall be
constructed below the level of the first finished
floor. This does not preclude the construction of:
I. Stairways;
2. Shearwalls essentially perpendicular to
breaking waves;
3. Shearwalls essentially parallel to breaking
waves which do not exceed a maximum of 20% of
the building length;
4. Wind or sand screens constructed of fabric
or wire mesh;
5. Light open lattice partitions with individual
wooden lattice strips no greater than 3/4"
thick or 3" wide;
6. Elevator shafts;
7. Breakaway or frangible walls; or
8. Substantial walls constructed above the wave
action and storm surge expected under design
storm conditions.
(c) Building and Floor Elevations
The minimum elevation for the underside of the
building support structure (excluding foundation) shall
be above the elevation of the design breaking wave
crests or wave uprush superimposed on the storm surge
with dynamic wave setup expected under design storm
conditions. The elevation of the storm surge with
dynamic wave setup shall be either the elevation
established by the Florida Department of Natural
Resources Coastal Construction Control Line Study or
the base flood elevation for the specific area
established by the Federal Emergency Management Agency
as determined by the design engineer.
(d) Erosion and Desiqn Grade
The elevation of the soil surface to be used in
the design of foundations, calculation of pile
reactions and bearing capacities shall not be greater
than that which would result from the erosion reason-
ably anticipated as a result of design storm conditions
Calculation of the design grade shall take into account
localized scour due to the presence of structural
components. Erosion computations for foundation design
shall consider all vertical and lateral erosion and
scour-producing forces.
(e) Wave Force Desiqn
1. Calculations for wave forces resulting from
design storm conditions on building foundations and
superstructures may be based upon the minimum criteria
and methods prescribed in the Naval Facilities
Engineering Command Design Manual, NAVFAC DM-26~
U.S. Department of Navy; Shore Protection Manual, U.S.
Department of the ARmy Corps of Engineers; U.S.
Department of the Army Coastal Engineering Research
Center Technical Papers and Reports; the Technical and
Design Memoranda of the Division of Beaches and Shores,
Florida Department of Natural Resources; or other
professionally recognized methodologies which produce
equivilent design criteria.
2. Breaking, broken, and nonbreaking waves shall be
considered as applicable. Design wave loading analysis
shall consider vertical uplift pressures and all
lateral pressures to include impact as well as dynamic
loading and the harmonic intensification resulting
from repetitive waves.
(f) Hydrostatic Loads
Calculations for hydrostatic loads shall consider
the maximum water pressure resulting from a fully
peaked, breaking wave superimposed ~pon the design
storm surge with dynamic wave setup. Both free and
hydrostatic loads shall be considered. Hydrostatic
loads which are confined shall be determined using the
maximum elevation to which the confined water would
freely rise if unconfined. Vertical hydrostatic loads
shall be considered both vertically downward and up-
ward on horizontal or inclined surfaces of major
structures (e.g. floors, slabs, roofs, walls). Lateral
hydrostatic loads shall be considered as forces acting
horizontally above and below grade on vertical or
inclined surfaces. Hydrostatic loads on irregular
or curved geometric surfaces shall be determined by
considering the separate vertical and horizontal
components acting simultaneously under the distri-
bution of the hudrostatic pressures.
(g) Hydrodynamic Loads
Hydrodynamic loads shall consider the maximum
water pressures resulting from the motion of the ware
mass asso'ciated with the design storm. Full intensi~
loading shall be applied'on all structural surfaces
above the design grade which would affect the flow
velocities.
(h) Design Conditions - General
Foundations for all major structures shall be
designed for the horizontal and vertical pres
generated by wave forces between the elevation o~
the design breaking wave crests or wave uprush
superimposed upon the storm surge and the stable
soil elevation of the site.
Ail major structures, except mobile homes, shall
at a minimum be designed' and constructed in
accordance with Section 1205 of the 1986 revisio~
to the 1985 Standard Building Code using a faste~
mile~wind velocity of One Hundred Ten (110) mph.
Appropriate shape factors shall be applied for
resistance against overturning and uplift as
required elsewhere in this code. Internal
pressure on internal walls, ceilings and floors
resulting from damaged windows or doors shall al
be considered in the design unless the specified
windows and doors have bee~ tested by an approve(
testing agency and have been shown to be capable
of withstanding the design pressures required
herein.
Mobile homes shall conform to the Federal Mobile
Home Construction and Safety Standards of the
Uniform Standards Code ANSI book A~l19.1, ~
to S. 320.823, Florida Statutes, in addition to
the other requirements contained in this chapter
Section 109.3 - Structural Requirements for Nonhabiti
Major Structures
Nonhabitable major structures need not meet the
specific structural requirements'of Section 109.2,
except that they shall be designed to produce the
minimum adverse impact on the beach and dune system
and shall comply with the applicable standards of
construction found elsewhere in this code. All sewa~
treatment and public water supply systems shall be
flood~proofed to prevent infiltration of surface wat
anticipated under design storm conditions. Undergrol
utilities, excluding pad transformers and vaults,
shall be flood-proofed to prevent infiltration of
surface water expected under design storm conditions
or shall otherwise be designed to function when sub-
merged under such storm conditions.
Section 109.4 - Structural Requirements for Minor
Structures
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Minor structures need not meet the specific structur~
requirements of Section 109.2, except that they shal]
be designed to produce the minimum adverse impact on
the beach and dune system and shall comply with the
applicable standards of construction found elsewhere
in this Code.
Section 109.5 - Location of Construction
Construction, except for elevated walkways, lifeguar~
support stands, piers, beach access ramps, gazebos,
and coastal or shore protection structures, shall be
located a sufficient distance landward of the beach
to permit natural shoreline fluctuations and to
preserve dune stability. Construction, including
excavations, may occur to the extent that the
storm buffering and protection capability of the dun~
is not diminished.
Section 109.6 - Public Access
Where the public has established an accessway
pr±vate lands to lands seaward of mean high tide or
water line by prescription, prescriptive easement, o]
any other legal means, development or construction
shall not interfere with such right of access unless
a comparable alternative accessway is provided. The
developer shall have the right to improve, consoli-
date, or relocate such public accessways so long as
they are:
(a)
Of substantially similar quality and convenienc~
to the public;
(b) Approved by the local government; and
(c)
Consistent with the coastal management element
of the local comprehensive plan adopted pur-
suant to SeCtion 163.3178, Florida Statutes.
Section 109.7 - References
Assistance in determining the design parameters and
methodologies necessary to comply with the require-
ments of this Chapter may be obtained from:
Shore Protection Manual, U.S. Army Corps of
Engineers, 4th edition,
1984.
U.S. Department of the Army, Coastal Engineering
Research Center's Technical Papers and Re
Florida Department of Natural Resources, Divisiol
of Beaches and Shores Technical and Design
Memoranda.
Naval Facilities Engineering Command Design
Manual, NACFAC DM-26, U.S. Department of
the Navy.
Section 2: Ail ordinances or parts of ordinances in
conflict herewith are hereby repealed.
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e
Section 3: Should any section or provision of this
Ordinance or any portion thereof be declared by a Court of
competent jurisdiction to be invalid, such decision shall not
affect the remainder of this Ordinance.
Section 4: This Ordinance shall become effective
immediately upon passage.
FIRST READING this ~t~day of '~.~-~7- , 1986.
SECOND READING AND FINAL PASSAGE this /~day of
· 1986.
ATTEST:
CITY OF BOYNTON BEACH, FLORIDA
VICE MAYORu-
CO~JNCIL MEMBER
COH~CIL ~E~BE~,~/t
~Ci~y·
( SEAL
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