HomeMy Public PortalAbout120_050_ Text Amendment freeboard 1of1 MAYOR y4 CITY MANAGER
Jason Buelterman • Diane Schleicher
CITY COUNCIL CITY CLERK
Wanda Doyle,Mayor Pro Tem M Janet LeViner
Barry Brown
Rob Callahan CITY ATTORNEY
Bill Garbett :y � Edward M.Hughes
Monty Parks -14117to
Paul Wolff
CITY OF TYBEE ISLAND
City Council Agenda Item Request
Agenda Item Requests and supporting documentation must be submitted to the Clerk of Council by
4:00PM on the Thursday prior to the next scheduled Council meeting. If this form is received after the
deadline, the item will be listed on the next scheduled agenda.
Council Meeting Date for Request: January 9, 2014
Item: Public Hearing
Explanation: Text Amendment—Ordinance 01-2014; Article 8, Flood Damage Prevention; City of Tybee
Island, petitioner; consideration of increased freeboard requirement
Budget Line Item Number (if applicable): N/A
Paper Work: Ai Attached*
Audio/Video Presentation**
* Electronic submissions are requested but not required. Please email to
jleviner@cityoftybee.org.
** Audio/video presentations must be submitted to the IT department at City Hall
by 4:00PM on the Thursday prior to the scheduled meeting.
Submitted by: Dianne Otto
Phone/Email: (912) 472-5031 /dotto@cityoftybee.org
Comments:
Date given to Clerk of Council: January 2, 2014
* * *
P.O. Box 2749—403 Butler Avenue,Tybee Island, Georgia 31328-2749 *Certified*
(866) 786-4573—FAX (866) 786-5737 y City of 1
w Ethics L f
www.cityoftybee.org
.>474
PLANNING COMMISSION
NOTICE OF DETERMINATION
Meeting date: December 17, 2013
Project Name/Description: Article 8—Flood Damage Prevention
Action Requested: Text Amendment
Special Review Subdivision:
Site Plan Approval Sketch Plan Approval Conceptual
Zoning Variance Preliminary Plan Approval
Amendment to Zoning Map Final Plat Approval
Text Amendment to Land Development Code X Minor Subdivision Major Subdivision
Petitioner has met all documentation requirements, all external approval requirements, and all code
requirements, except for the following:
VOTE FOR AGAINST COMMENTS
Bishop X
Borkowski _ X Second
Bramble X
Callahan X Motion to approve to 3 feet
Marion X Vice Chair
McNaughton X
Parks Chair Absent
The Planning Commission recommends: EZ Approval n Denial Continued
Planning Commission Ch. . Date: / PT ` c3
Planning& Zoning Manager: =" . ., _ O. Date: i a,-1 63-1,
Sec. 8-190. Specific standards.
In all areas of special flood hazard designated as A1-30, AE, AH, A (with estimated BFE), the
following provisions are required:
(1) New construction and/or substantial improvements. Where base flood elevation data are
available, new construction and/or substantial improvement of any structure or manufactured
home shall have the lowest floor, including basement, elevated no lower than one-foot three
feet above the base flood elevation. Should solid foundation perimeter walls be used to elevate
a structure, openings sufficient to facilitate the unimpeded movements of flood waters shall be
provided in accordance with standards of subsection 8-180(4), "Elevated Buildings."
a. All heating and air conditioning equipment and components (including ductwork), all
electrical, ventilation, plumbing fixtures and other service facilities shall be elevated at or
above one-foot three feet above the base flood elevation.
(2) Non-residential construction. New construction and/or the substantial improvement of any
structure located in Al-30, AE, or AH zones, may be flood-proofed in lieu of elevation. The
structure, together with attendant utility and sanitary facilities, must be designed to be water
tight to one-foot three feet above the base flood elevation, with walls substantially impermeable
to the passage of water, and structural components having the capability of resisting hydrostatic
and hydrodynamic loads and the effect of buoyancy. A registered professional engineer or
architect shall certify that the design and methods of construction are in accordance with
accepted standards of practice for meeting the provisions above, and shall provide such
certification to the official as set forth above and in subsection 8-170(6).
(3) Standards for manufactured homes and recreational vehicles—Where base flood elevation data
are available:
a. All manufactured homes placed and/or substantially improved on: (1) individual lots or
parcels, (2) in new and/or substantially improved manufactured home parks or
subdivisions, (3) in expansions to existing manufactured home parks or subdivisions, or (4)
on a site in an existing manufactured home park or subdivision where a manufactured
home has incurred "substantial damage"as the result of a flood, must have the lowest floor
including basement, elevated no lower than arse-foot three feet above the base flood
elevation.
b. Manufactured homes placed and/or substantially improved in an either existing
manufactured home park or subdivision may be elevated so that:
1. The lowest floor of the manufactured home is elevated no lower than ore-foot three
feet above the level of the base flood elevation; or
2. The manufactured home chassis is elevated and supported by reinforced piers (or
other foundation elements of at least an equivalent strength) of no less than 36 inches
in height above grade.
c. All manufactured homes must be securely anchored to an adequately anchored foundation
system to resist flotation, collapse and lateral movement. (ref. subsection 8-180(6) above)
d. All recreational vehicles placed on sites must either:
1. Be on the site for fewer than 180 consecutive days;
2. Be fully licensed and ready for highway use, (a recreational vehicle is ready for
highway use if it is licensed, on its wheels or jacking system, attached to the site only
by quick disconnect type utilities and security devices, and has no permanently
attached structures or additions); or
3. The recreational vehicle must meet all the requirements for "New Construction",
including the anchoring and elevation requirements of subsections (3)a. and c.,
above.
(4) Floodway. Located within areas of special flood Hazard established in section 8-080 are areas
designated as floodway. A floodway may be an extremely hazardous area due to velocity
floodwaters, debris or erosion potential. In addition, the area must remain free of encroachment
in order to allow for the discharge of the base flood without increased flood heights. Therefore,
the following provisions shall apply:
a. Encroachments are prohibited, including earthen fill, new construction, substantial
improvements or other development within the regulatory floodway. Development may be
permitted however, provided it is demonstrated through hydrologic and hydraulic analyses
performed in accordance with standard engineering practice that the encroachment shall
not result in any increase in flood levels or floodway widths during a base flood discharge.
A registered professional engineer must provide supporting technical data and certification
thereof.
b. Only if subsection (4)a. above is satisfied, then any new construction or substantial
improvement shall comply with all other applicable flood hazard reduction provisions of this
division.
Sec. 8-200. Building standards for streams without established base flood elevations
and/or floodway (A-zones).
Located within the areas of special flood hazard established in section 8-080, where streams exist
but no base flood data have been provided (A-zones), or where base flood data have been provided but a
Floodway has not been delineated, the following provisions apply:
(1) When base flood elevation data or floodway data have not been provided in accordance with
section 8-080), then the building and zoning department shall obtain, review, and reasonably
utilize any scientific or historic base flood elevation and floodway data available from a federal,
state, or other source, in order to administer the provisions of this division. Only if data are not
available from these sources, then the following provisions (subsections (2) and (3)) shall apply:
(2) No encroachments, including structures or fill material, shall be located within an area equal to
the width of the stream or 25 feet, whichever is greater, measured from the top of the stream
bank, unless certification by a registered professional engineer is provided demonstrating that
such encroachment shall not result in more than one foot increase in flood levels during the
occurrence of the base flood discharge.
(3) In special flood hazard areas without base flood elevation data, new construction and
substantial improvements of existing structures shall have the lowest floor of the lowest
enclosed area (including basement) elevated no less than three feet above the highest adjacent
grade at the building site. (NOTE: Require the lowest floor to be elevated one-foot three feet
above the estimated base flood elevation in A-Zone areas where a limited detail study has been
completed). Openings sufficient to facilitate the unimpeded movements of floodwaters shall be
provided in accordance with standards of subsection 8-180(4), "Elevated buildings."
a. All heating and air conditioning equipment and components (including ductwork), all
electrical, ventilation, plumbing fixtures, and other service facilities shall be elevated no
less than three feet above the highest adjacent grade at the building site.
The Building and Zoning Department shall certify the lowest floor elevation level and the
record shall become a permanent part of the permit file.
Sec. 8-220. Standards for areas of shallow flooding (AO zones).
Areas of special flood hazard established in Section 8-080, may include designated "AO" shallow
flooding areas. These areas have base flood depths of one to three feet above ground, with no clearly
defined channel. The following provisions apply:
(1) All new construction and substantial improvements of residential and non-residential structures
shall have the lowest floor, including basement, elevated to the flood depth number specified on
the flood insurance rate Map (FIRM), above the highest adjacent grade. If no flood depth
number is specified, the lowest floor, including basement, shall be elevated at least three feet
above the highest adjacent grade. Openings sufficient to facilitate the unimpeded movements of
flood waters shall be provided in accordance with standards of subsection 8-1 80(4), "Elevated
buildings".
The surveyor, architect, or engineer shall certify the lowest floor elevation level and the record
shall become a permanent part of the permit file.
(2) New construction or the substantial improvement of a non-residential structure may be flood-
proofed in lieu of elevation. The structure, together with attendant utility and sanitary facilities,
must be designed to be water tight to the specified FIRM flood level plus one-boat three feet,
above highest adjacent grade, with walls substantially impermeable to the passage of water,
and structural components having the capability of resisting hydrostatic and hydrodynamic loads
and the effect of buoyancy. A registered professional engineer or architect shall certify that the
design and methods of construction are in accordance with accepted standards of practice for
meeting the provisions above, and shall provide such certification to the official as set forth
above and as required in subsections 8-160(1)c. and (2).
(3) Drainage paths shall be provided to guide floodwater around and away from any proposed
structure.
Sec. 8-230. Coastal high hazard areas (V-zones).
Located within the areas of special flood hazard established in Section 8-080, are areas designated
as coastal high hazard areas (V-zones). These areas have special flood hazards associated with wave
action and storm surge, therefore, the following provisions shall apply:
(1) All new construction and substantial improvements of existing structures shall be located
landward of the reach of mean high tide;
(2) All new construction and substantial improvements of existing structures shall be elevated on
piles, columns, or shear walls parallel to the flow of water so that the bottom of the lowest
supporting horizontal structural member (excluding pilings or columns) is located no lower than
one-foot three feet above the base flood elevation level. All space below the lowest supporting
member shall remain free of obstruction or constructed with non-supporting breakaway walls.
Open wood lattice work or decorative screening may be permitted for aesthetic purposes only
and must be designed to wash away in the event of abnormal wave action and in accordance
with subsection below;
(3) All new construction and substantial improvements of existing structures shall be securely
anchored on pilings, columns, or shear walls; and
(4) All pile and column foundations and the structures attached thereto shall be anchored to resist
flotation, collapse, and lateral movement due to the combined effects of wind and water loads
acting simultaneously on ALL building components, both (non-structural and structural). Water
loading values shall equal or exceed those of the base flood. Wind loading values shall be in
accordance with the most current edition of the (ICC) International Building Codes.
(5) A registered professional engineer or architect shall certify that the design, specifications and
plans for construction are in compliance with the provisions contained in subsection (2) through
(4) herein.
(6) All space below the lowest horizontal supporting member must remain free of obstruction. Open
wood lattice work or decorative screening may be permitted for aesthetic purposes only and
must be designed to wash away in the event of abnormal wave action without causing structural
damage to the supporting foundation or elevated portion of the structure. The following design
specifications are allowed:
a. No solid walls shall be allowed; and
b. Material shall consist of open wood lattice or mesh screening only.
c. If aesthetic open wood lattice work or screening is utilized, any enclosed space shall not be
used for human habitation, but shall be designed to be used only for parking of vehicles,
building access, or limited storage of maintenance equipment used in connection with the
premises.
(7) Prior to construction, plans for any structures having open wood latticework or decorative
screening must be shown on the plans submitted to the city building and zoning department for
review and approval;
(8) Any alteration, repair, reconstruction or improvement to any structure shall not enclose the
space below the lowest floor except with open wood latticework or decorative screening, as
provided in this section.
(9) There shall be no fill used as structural support. Non-compacted fill may be used around the
perimeter of a building for landscaping/aesthetic purposes provided the fill will wash out from
storm surge, (thereby rendering the building free of obstruction) prior to generating excessive
loading forces, ramping effects, or wave deflection. The building and zoning department shall
approve design plans for landscaping/aesthetic fill only after the applicant has provided an
analysis by an engineer, architect, and/or soil scientist, which demonstrates that the following
factors have been fully considered:
a. Particle composition of fill material does not have a tendency for excessive natural
compaction;
b. Volume and distribution of fill will not cause wave defection to adjacent properties; and
c. Slope of fill will not cause wave run-up or ramping.
(10) There shall be no alteration of sand dunes or mangrove stands, which would increase potential
flood damage;
(11) Prohibit the placement of manufactured homes (mobile homes), except in an existing
manufactured homes park or subdivision. A replacement manufactured home may be placed on
a lot in an existing manufactured home park or subdivision provided the anchoring standards of
subsection 8-190(3) are met.
ORDINANCE NO. 01-2014
AN ORDINANCE TO AMEND THE CODE OF ORDINANCES
PERTAINING TO ARTICLE 8 REGARDING
FLOOD DAMAGE PREVENTION
FOR THE CITY OF TYBEE ISLAND, GEORGIA
WHEREAS, the duly elected governing authority for the City of Tybee Island, Georgia,
is authorized under Article 9, Section 2, Paragraph 3 of the Constitution of the State of Georgia
to adopt reasonable ordinances to protect and improve the public health, safety, and welfare of
the citizens of Tybee Island, Georgia, and
WHEREAS, the duly elected governing authority for the City of Tybee Island, Georgia,
is the Mayor and Council thereof, and
WHEREAS, the governing authority desires to adopt ordinances under its police, zoning,
and home rule powers, and
WHEREAS, the City of Tybee Island so as to amend Article 8, Flood Damage
Prevention, so as to increase the "freeboard" requirement from one foot to "three feet" and to
amend Sections 8-190, 8-220, and 8-230 to accomplish such change; and
NOW, THEREFORE, it is hereby ordained by the governing authority of the City of
Tybee Island that Article 8, Sections 8-190, 8-200, 8-220, and 8-230 of the Code of Ordinances
of the City of Tybee Island shall be amended.
SECTION 1
Sections 8-190, 8-220, and 8-230 are hereby amended and will hereafter read as follows:
Sec. 8-190. Specific standards.
In all areas of special flood hazard designated as A1-30, AE, AH, A (with estimated BFE), the
following provisions are required:
(1) New construction and/or substantial improvements. Where base flood elevation data are
available, new construction and/or substantial improvement of any structure or manufactured
home shall have the lowest floor, including basement, elevated no lower than three feet above
the base flood elevation. Should solid foundation perimeter walls be used to elevate a structure,
openings sufficient to facilitate the unimpeded movements of flood waters shall be provided in
accordance with standards of subsection 8-180(4), "Elevated Buildings."
a. All heating and air conditioning equipment and components (including ductwork), all
electrical, ventilation, plumbing fixtures and other service facilities shall be elevated at or
above three feet above the base flood elevation.
(2) Non-residential construction. New construction and/or the substantial improvement of any
structure located in A1-30, AE, or AH zones, may be flood-proofed in lieu of elevation. The
structure, together with attendant utility and sanitary facilities, must be designed to be water
tight to three feet above the base flood elevation, with walls substantially impermeable to the
passage of water, and structural components having the capability of resisting hydrostatic and
hydrodynamic loads and the effect of buoyancy. A registered professional engineer or architect
shall certify that the design and methods of construction are in accordance with accepted
standards of practice for meeting the provisions above, and shall provide such certification to
the official as set forth above and in subsection 8-170(6).
(3) Standards for manufactured homes and recreational vehicles—Where base flood elevation data
are available:
a. All manufactured homes placed and/or substantially improved on: (1) individual lots or
parcels, (2) in new and/or substantially improved manufactured home parks or
subdivisions, (3) in expansions to existing manufactured home parks or subdivisions, or (4)
on a site in an existing manufactured home park or subdivision where a manufactured
home has incurred "substantial damage" as the result of a flood, must have the lowest floor
including basement, elevated no lower than three feet above the base flood elevation.
b. Manufactured homes placed and/or substantially improved in an either existing
manufactured home park or subdivision may be elevated so that:
1. The lowest floor of the manufactured home is elevated no lower than three feet above
the level of the base flood elevation; or
2. The manufactured home chassis is elevated and supported by reinforced piers (or
other foundation elements of at least an equivalent strength) of no less than 36 inches
in height above grade.
c. All manufactured homes must be securely anchored to an adequately anchored foundation
system to resist flotation, collapse and lateral movement. (ref. subsection 8-180(6) above)
d. All recreational vehicles placed on sites must either:
1. Be on the site for fewer than 180 consecutive days;
2. Be fully licensed and ready for highway use, (a recreational vehicle is ready for
highway use if it is licensed, on its wheels or jacking system, attached to the site only
by quick disconnect type utilities and security devices, and has no permanently
attached structures or additions); or
3. The recreational vehicle must meet all the requirements for "New Construction",
including the anchoring and elevation requirements of subsections (3)a, and c.,
above.
(4) Floodway. Located within areas of special flood Hazard established in section 8-080 are areas
designated as floodway. A floodway may be an extremely hazardous area due to velocity
floodwaters, debris or erosion potential. In addition, the area must remain free of encroachment
in order to allow for the discharge of the base flood without increased flood heights. Therefore,
the following provisions shall apply:
a. Encroachments are prohibited, including earthen fill, new construction, substantial
improvements or other development within the regulatory floodway. Development may be
permitted however, provided it is demonstrated through hydrologic and hydraulic analyses
performed in accordance with standard engineering practice that the encroachment shall
not result in any increase in flood levels or floodway widths during a base flood discharge.
A registered professional engineer must provide supporting technical data and certification
thereof.
b. Only if subsection (4)a. above is satisfied, then any new construction or substantial
improvement shall comply with all other applicable flood hazard reduction provisions of this
division.
Sec. 8-200. Building standards for streams without established base flood
elevations and/or floodway (A-zones).
Located within the areas of special flood hazard established in section 8-080, where streams exist
but no base flood data have been provided (A-zones), or where base flood data have been provided but a
Floodway has not been delineated,the following provisions apply:
(1) When base flood elevation data or floodway data have not been provided in accordance with
section 8-080), then the building and zoning department shall obtain, review, and reasonably
utilize any scientific or historic base flood elevation and floodway data available from a federal,
state, or other source, in order to administer the provisions of this division. Only if data are not
available from these sources, then the following provisions (subsections (2) and (3)) shall apply:
(2) No encroachments, including structures or fill material, shall be located within an area equal to
the width of the stream or 25 feet, whichever is greater, measured from the top of the stream
bank, unless certification by a registered professional engineer is provided demonstrating that
such encroachment shall not result in more than one foot increase in flood levels during the
occurrence of the base flood discharge.
(3) In special flood hazard areas without base flood elevation data, new construction and
substantial improvements of existing structures shall have the lowest floor of the lowest
enclosed area (including basement) elevated no less than three feet above the highest adjacent
grade at the building site. (NOTE: Require the lowest floor to be elevated three feet above the
estimated base flood elevation in A-Zone areas where a limited detail study has been
completed). Openings sufficient to facilitate the unimpeded movements of floodwaters shall be
provided in accordance with standards of subsection 8-1 80(4), "Elevated buildings."
a. All heating and air conditioning equipment and components (including ductwork), all
electrical, ventilation, plumbing fixtures, and other service facilities shall be elevated no
less than three feet above the highest adjacent grade at the building site.
The Building and Zoning Department shall certify the lowest floor elevation level and the
record shall become a permanent part of the permit file.
Sec. 8-220. Standards for areas of shallow flooding (AO zones).
Areas of special flood hazard established in Section 8-080, may include designated 'AO" shallow
flooding areas. These areas have base flood depths of one to three feet above ground, with no clearly
defined channel. The following provisions apply:
(1) All new construction and substantial improvements of residential and non-residential structures
shall have the lowest floor, including basement, elevated to the flood depth number specified on
the flood insurance rate Map (FIRM), above the highest adjacent grade. If no flood depth
number is specified, the lowest floor, including basement, shall be elevated at least three feet
above the highest adjacent grade. Openings sufficient to facilitate the unimpeded movements of
flood waters shall be provided in accordance with standards of subsection 8-180(4), "Elevated
buildings".
The surveyor, architect, or engineer shall certify the lowest floor elevation level and the record
shall become a permanent part of the permit file.
(2) New construction or the substantial improvement of a non-residential structure may be flood-
proofed in lieu of elevation. The structure, together with attendant utility and sanitary facilities,
must be designed to be water tight to the specified FIRM flood level plus three feet, above
highest adjacent grade, with walls substantially impermeable to the passage of water, and
structural components having the capability of resisting hydrostatic and hydrodynamic loads and
the effect of buoyancy. A registered professional engineer or architect shall certify that the
design and methods of construction are in accordance with accepted standards of practice for
meeting the provisions above, and shall provide such certification to the official as set forth
above and as required in subsections 8-160(1)c. and (2).
(3) Drainage paths shall be provided to guide floodwater around and away from any proposed
structure.
Sec. 8-230. Coastal high hazard areas (V-zones).
Located within the areas of special flood hazard established in Section 8-080, are areas designated
as coastal high hazard areas (V-zones). These areas have special flood hazards associated with wave
action and storm surge, therefore, the following provisions shall apply:
(1) All new construction and substantial improvements of existing structures shall be located
landward of the reach of mean high tide;
(2) All new construction and substantial improvements of existing structures shall be elevated on
piles, columns, or shear walls parallel to the flow of water so that the bottom of the lowest
supporting horizontal structural member (excluding pilings or columns) is located no lower than
three feet above the base flood elevation level. All space below the lowest supporting member
shall remain free of obstruction or constructed with non-supporting breakaway walls. Open
wood lattice work or decorative screening may be permitted for aesthetic purposes only and
must be designed to wash away in the event of abnormal wave action and in accordance with
subsection below;
(3) All new construction and substantial improvements of existing structures shall be securely
anchored on pilings, columns, or shear walls; and
(4) All pile and column foundations and the structures attached thereto shall be anchored to resist
flotation, collapse, and lateral movement due to the combined effects of wind and water loads
acting simultaneously on ALL building components, both (non-structural and structural). Water
loading values shall equal or exceed those of the base flood. Wind loading values shall be in
accordance with the most current edition of the (ICC) International Building Codes.
(5) A registered professional engineer or architect shall certify that the design, specifications and
plans for construction are in compliance with the provisions contained in subsection (2) through
(4) herein.
(6) All space below the lowest horizontal supporting member must remain free of obstruction. Open
wood lattice work or decorative screening may be permitted for aesthetic purposes only and
must be designed to wash away in the event of abnormal wave action without causing structural
damage to the supporting foundation or elevated portion of the structure. The following design
specifications are allowed:
a. No solid walls shall be allowed; and
b. Material shall consist of open wood lattice or mesh screening only.
c. If aesthetic open wood lattice work or screening is utilized, any enclosed space shall not be
used for human habitation, but shall be designed to be used only for parking of vehicles,
building access, or limited storage of maintenance equipment used in connection with the
premises.
(7) Prior to construction, plans for any structures having open wood latticework or decorative
screening must be shown on the plans submitted to the city building and zoning department for
review and approval;
(8) Any alteration, repair, reconstruction or improvement to any structure shall not enclose the
space below the lowest floor except with open wood latticework or decorative screening, as
provided in this section.
(9) There shall be no fill used as structural support. Non-compacted fill may be used around the
perimeter of a building for landscaping/aesthetic purposes provided the fill will wash out from
storm surge, (thereby rendering the building free of obstruction) prior to generating excessive
loading forces, ramping effects, or wave deflection. The building and zoning department shall
approve design plans for landscaping/aesthetic fill only after the applicant has provided an
analysis by an engineer, architect, and/or soil scientist, which demonstrates that the following
factors have been fully considered:
a. Particle composition of fill material does not have a tendency for excessive natural
compaction;
b. Volume and distribution of fill will not cause wave defection to adjacent properties; and
c. Slope of fill will not cause wave run-up or ramping.
(10) There shall be no alteration of sand dunes or mangrove stands, which would increase potential
flood damage;
(11) Prohibit the placement of manufactured homes (mobile homes), except in an existing
manufactured homes park or subdivision. A replacement manufactured home may be placed on
a lot in an existing manufactured home park or subdivision provided the anchoring standards of
subsection 8-190(3) are met.
SECTION 2
The sections, paragraphs, sentences, clauses and phrases of this ordinance are severable
and, if any phrase, clause, sentence, paragraph, or section of this ordinance shall be declared
illegal or invalid by the valid judgment or decree of any court of competent jurisdiction, such
illegality shall not affect any of the remaining phrases, clauses, sentences, paragraphs and
sections of this ordinance.
SECTION 3
All ordinances and parts of ordinances in conflict herewith are expressly repealed.
SECTION 4
It is the intention of the governing body, and it is hereby ordained, that the provisions of
this ordinance shall become effective and be made a part of the Code of Ordinances, City of
Tybee Island, Georgia, and the sections of this ordinance may be renumbered to accomplish such
intention.
SECTION 5
This ordinance shall be effective upon its adoption by the Mayor and Council pursuant to
the ordinances of the City.
ADOPTED THIS DAY OF , 2014.
MAYOR
A1'1'EST:
CLERK OF COUNCIL
FIRST READING:
SECOND READING:
ENACTED:
EMH/TybeefOrdinances/2014/01-2014-Secs. 8-190,8-200,8-220,8-230 Flood damage prevention-fr DO-
12.26.13-clean
FOR THE PLANNING COMMISSION MEETING OF: December 17, 2013
FOR THE CITY COUNCIL MEETING OF: January 9, 2014
Consideration of increased freeboard requirement
Packet contents:
A. LDC Article 8, Flood Damage Prevention (pages 1 — 21)
a. Section 8-060, Definitions —"freeboard" (page 7)
b. proposed change from one foot to two foot or three foot (pages 16— 19)
B. Community Rating System Coordinator's Manual (pages 22 - 37)
a. Glossary—"freeboard" (page 23)
b. Higher Regulatory Standards (pages 24—37)
i. Freeboard (pages 32 —37)
C. Floodplain Management Requirements (pages 38 & 39)
a. Compensatory Storage (page 39)
D. CRS Credit for Higher Regulatory Storage (pages 40 &41)
a. compensatory storage illustration (page 41)
E. City of Griffin, Georgia (page 42)
F. Evaluation of the National Flood Insurance Program's Building Standards (pages 43 —49)
a. the cost of incorporating freeboard (page 47)
G. Using Freeboard to Elevate Structures above Predicted Floodwaters (pages 50 &51)
12/08/2013
PART II -CODE OF ORDINANCES
APPENDIX A- LAND DEVELOPMENT CODE
ARTICLE 8. FLOOD DAMAGE PREVENTION
ARTICLE 8. FLOOD DAMAGE PREVENTION '
111
1. - GENERALLY
DIVISION 2. -ADMINISTRATION
DIVISION 3. - PROVISIONS FOR FLOOD HAZARD REDUCTION
FOOTNOTE(S):
--- (4) ---
Editor's note—An ordinance adopted Sept, 26, 2008, repealed the former Art. 8, §§ 8-010-8-170, and
enacted a new Art. 8 as set out herein. The former Art. 8 pertained to similar subject matter and derived
from the original codification, (Back)
Tybee Island, Georgia, Code of Ordinances Page 1
PART II -CODE OF ORDINANCES
APPENDIX A- LAND DEVELOPMENT CODE
ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 1. GENERALLY
DIVISION 1. GENERALLY
Sec. 8-010. Statutory authorization.
Sec. 8-020. Findings of fact.
Sec. 8-030. Statement of purpose.
Sec. 8-040. Objectives.
Sec. 8-050. Variance procedures.
Sec. 8-060. Definitions.
Sec. 8-070. Lands to which this article applies.
Sec. 8-080. Basis for area of special flood hazard.
Sec. 8-090. Establishment of development permit.
Sec. 8-100. Compliance.
Sec. 8-110. Abrogation and greater restrictions.
Sec. 8-120. Interpretation.
Sec. 8-130.Warning and disclaimer of liability.
See. 8-140. Penalties for violation.
Sec. 8-010. Statutory authorization.
Article IX, Section II of the Constitution of the State of Georgia and Section 36-1-20(a) of the Official
Code of Georgia Annotated have delegated the responsibility to local governmental units to adopt
regulations designed to promote the public health, safety, and general welfare of its citizenry. Therefore,
the mayor and council of the City of Tybee Island, Georgia does ordain as follows:
(Ord. of 9-26-2008, Art. 1, § A)
Sec. 8-020. Findings of fact.
(A) The flood hazard areas of Tybee island, Georgia are subject to periodic inundation which results in
loss of life and property, health and safety hazards, disruption of commerce and governmental
services, extraordinary public expenditures for flood relief and protection, and impairment of the tax
base, all of which adversely affect the public health, safety and general welfare.
(b) These flood losses are caused by the occupancy in flood hazard areas of uses vulnerable to floods,
which are inadequately elevated, flood-proofed, or otherwise unprotected from flood damages, and
by the cumulative effect of obstructions in floodplains causing increases in flood heights and
velocities.
(Ord. of 9-26-2008, Art. 1, § B)
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ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 1. GENERALLY
Sec. 8-030. Statement of purpose.
It is the purpose of this article are to promote the public health, safety and general welfare and to
minimize public and private losses due to flood conditions in specific areas by provisions designed to:
(1) Require that uses vulnerable to floods, including facilities, which serve such uses, be protected
against flood damage at the time of initial construction;
(2) Restrict or prohibit uses which are dangerous to health, safety and property due to water or
erosion hazards, or which increase flood heights, velocities, or erosion;
(3) Control filling, grading, dredging and other development which may increase flood damage or
erosion;
(4) Prevent or regulate the construction of flood barriers which will unnaturally divert flood waters or
which may increase flood hazards to other lands; and
(5) Control the alteration of natural floodplains, stream channels, and natural protective barriers,
which are involved in the accommodation of floodwaters.
(Ord. of 9-26-2008, Art. 1, § C)
Sec. 8-040. Objectives.
The objectives of this article are:
(1) To protect human life and health;
(2) To minimize damage to public facilities and utilities such as water and gas mains, electric,
telephone and sewer lines, streets and bridges located in floodplains;
(3) To help maintain a stable tax base by providing for the sound use and development of flood
prone areas in such a manner as to minimize flood blight areas;
(4) To minimize expenditure of public money for costly flood control projects;
(5) To minimize the need for rescue and relief efforts associated with flooding and generally
undertaken at the expense of the general public;
(6) To minimize prolonged business interruptions, and
(7) To insure that potential homebuyers are notified that property is in a flood area.
(Ord. of 9-26-2008, Art. 1, § D)
Sec. 8-050. Variance procedures.
(A) The planning commission as established by the mayor and council of Tybee Island, Georgia shall
hear and make recommendations to the Mayor and Council for appeals or variance from the
requirements of this article.
(B) Any person aggrieved by the decision of the mayor and council may appeal such decision to the
Superior Court of Chatham County, Georgia as provided in state law.
(C) Variances may be issued for the repair or rehabilitation of Historic Structures upon a determination
that the proposed repair or rehabilitation will not preclude the structure's continued designation as a
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DIVISION 1. GENERALLY
Historic Structure and the variance is the minimum to preserve the historic character and design of
the structure.
(D) Variances may be issued for development necessary for the conduct of a functionally dependent
use, provided the criteria of this article are met, no reasonable alternative exists, and the
development is protected by methods that minimize flood damage during the base flood and create
no additional threats to public safety.
(E) Variances shall not be issued within any designated floodway if ANY increase in flood levels during
the base flood discharge would result.
(F) In reviewing such requests, the planning commission shall consider all technical evaluations,
relevant factors, and all standards specified in this and other sections of this article.
(0) Conditions for variances:
(1) A variance shall be issued only when there is:
a. A finding of good and sufficient cause,
b. A determination that failure to grant the variance would result in exceptional hardship; and
c. A determination that the granting of a variance will not result in increased flood heights,
additional threats to public safety, extraordinary public expense, create nuisance, cause
fraud on or victimization of the public, or conflict with existing local laws or ordinances.
(2) The provisions of this article are minimum standards for flood loss reduction; therefore any
deviation from the standards must be weighed carefully. Variances shall only be issued upon a
determination that the variance is the minimum necessary, considering the flood hazard, to
afford relief; and, in the instance of an historic structure, a determination that the variance is the
minimum necessary so as not to destroy the historic character and design of the building.
(3) Any applicant to whom a variance is granted shall be given written notice specifying the
difference between the base flood elevation and the elevation of the proposed lowest floor and
stating that the cost of flood insurance will be commensurate with the increased risk to life and
property resulting from the reduced lowest floor elevation.
(4) Every applicant to whom a variance is granted from the elevation requirements for the lowest
floor elevation is required to have such variance noted on the deed and the plat to the deed for
the property on which the structure is, or is to be, located. Such notation shall read as follows:
A lowest floor elevation variance of feet has been approved by the City of Tybee Island
for a structure located on this property. The structure is identified as a (Note: SELECT ONE)
single-family, duplex of multi-family dwelling, or commercial building) located at
It should be noted that such variance may significantly increase the flood insurance premiums
for this property, as well as increase the likelihood of flood damage to the structure and its
contents. Said variance was issued upon petition of the property owner and was issued with the
owner's full knowledge of the consequences to the present and future owners which may result
therefrom.
A copy of the deed shall be filed by the owner with the building and zoning department of the
City of Tybee Island within two weeks of receipt of formal notification of approval of a variance
by the City of Tybee Island.
(5) The Building and Zoning Department Tybee Island, Georgia shall maintain the records of all
appeal actions and report any variances to the Federal Emergency Management Agency upon
request.
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ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 1. GENERALLY
(I) Upon consideration of the factors listed above and the purposes of this ordinance, the planning
commission and/or mayor and council may attach such conditions to the granting of variances
as it deems necessary to further the purposes of this article.
(Ord. of 9-26-2008, Art. 5)
Sec. 8-060. Definitions.
Unless specifically defined below, words or phrases used in this article shall be interpreted so as to
give them the meaning they have in common usage and to give this ordinance its most reasonable
application.
Accessory structure means a structure having minimal value and used for parking, storage and other
non-habitable uses, such as garages, carports, storage sheds, pole barns, hay sheds and the like.
Addition (to an existing building) means any walled and roofed expansion to the perimeter of a
building in which the addition is connected by a common load-bearing wall other than a firewall. Any
walled and roofed addition, which is connected by a firewall or is separated by an independent perimeter
load-bearing wall, shall be considered "new construction."
Appeal means a request for a review of the planning commission and/or mayor and council of Tybee
Island, Georgia interpretation of any provision of this article.
Area of shallow flooding means a designated AO or AH Zone on a community's Flood Insurance
Rate Map (FIRM) with base flood depths from one to three feet, and/or where a clearly defined channel
does not exist, where the path of flooding is unpredictable and indeterminate, and where velocity flow
may be evident.
Area of special flood hazard is the land in the floodplain within a community subject to a one percent
or greater chance of flooding in any given year. In the absence of official designation by the Federal
Emergency Management Agency, areas of special flood hazard shall be those designated by the local
community and referenced in section 8-080 herein.
"Base flood means the flood having a one percent chance of being equaled or exceeded in any
given year.
Base flood elevation (BFE) The elevation shown on the Flood Insurance Rate Map for Zones AE,
AH, Al—A30, AR, AR/A, AR/AE, AR/A1—A30, AR/AH, AR/A0, V1—V30, and VE that indicates the water
surface elevation resulting from a flood that has a one percent chance of equaling or exceeding that level
in any given year.
Basement means that portion of a building having its floor sub grade (below ground level) on all
sides.
Breakaway wall means a wall that is not part of the structure support of the building and is intended
through its design and construction to collapse under wind and water loads without causing collapse,
displacement, or other structural damage to the elevated portion of the building or supporting foundation
system.
Building, means any structure built for support, shelter, or enclosure for any occupancy or storage.
Critical facility means any public or private facility, which, if flooded, would create an added
dimension to the disaster or would increase the hazard to life and health. Critical facilities include:
(1) Structures or facilities that produce, use, or store highly volatile, flammable, explosive, toxic, or
water-reactive materials;
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ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 1. GENERALLY
(2) Hospitals and nursing homes, and housing for the elderly, which are likely to contain occupants
who may not be sufficiently mobile to avoid the loss of life or injury during flood and storm
events;
(3) Emergency operation centers or data storage centers which contain records or services that
may become lost or inoperative during flood and storm events; and generating plants, and other
principal points of utility lines.
(4) Generating plants, and other principal points of utility lines.
Development means any man-made change to improved or unimproved real estate, including, but
not limited to, buildings or other structures, mining, dredging, filling, grading, paving, excavating, drilling
operations, and storage of materials or equipment.
Elevated building means a non-basement building built to have the lowest floor of the lowest
enclosed area elevated above the ground level by means of fill, solid foundation perimeter walls, pilings,
columns, piers, or shear walls adequately anchored so as not to impair the structural integrity of the
building during a base flood event.
Existing construction Any structure for which the "start of construction" commenced before
November 22, 1972. [i.e., the effective date of the first floodplain management code or ordinance adopted
by the community as a basis for that community's participation in the National Flood Insurance Program
(NFIP)].
Existing manufactured home park or subdivision means a manufactured home park or subdivision for
which the construction of facilities for servicing the lots on which the manufactured homes are to be
affixed (including at a minimum the installation of utilities, the construction of streets, and final site grading
or the pouring of concrete pads) is completed before November 22, 1972. [i.e., the effective date of the
FIRST floodplain management regulations adopted by a community].
Expansion to an existing manufactured home park or subdivision means the preparation of additional
sites by the construction of facilities for servicing the lots on which the manufactured homes are to be
affixed, including the installation of utilities, the construction of streets, and either final site grading or the
pouring of concrete pads.
Flood or flooding means a general and temporary condition of partial or complete inundation of
normally dry land areas from:
a. The overflow of inland or tidal waters; or
b. The unusual and rapid accumulation or runoff of surface waters from any source.
Flood hazard boundary map (FHBM) means an official map of a community, issued by the Federal
Insurance Administration, where the boundaries of areas of special flood hazard have been defined as
Zone A.
Flood insurance rate map (FIRM) means an official map of a community, issued by the Federal
Insurance Administration, delineating the areas of special flood hazard and/or risk premium zones
applicable to the community.
Flood insurance study the official report by the Federal Insurance Administration evaluating flood
hazards and containing flood profiles and water surface elevations of the base flood.
Floodplain means any land area susceptible to flooding.
Flood proofing, means any combination of structural and non-structural additions, changes, or
adjustments to structures, which reduce or eliminate flood damage to real estate or improved real
property, water and sanitary facilities, structures and their contents.
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ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 1.GENERALLY
Floodway means the channel of a river or other watercourse and the adjacent land areas that must
be reserved in order to discharge the base flood without cumulatively increasing the water surface
elevation more than a designated height.
Freeboard means a factor of safety usually expressed in feet above a flood level for purposes of
floodplain management.
Freeboard tends to compensate for the many unknown factors that could contribute to flood heights
greater than the height calculated for a selected size flood and floodway conditions, such as wave action,
bridge openings, and the hydrological effect of urbanization of the watershed.
Functionally dependent use means a use that cannot perform its intended purpose unless it is
located or carried out in close proximity to the water. The term includes docking facilities, port facilities
that are necessary for the loading and unloading of cargo or passengers, and ship building and repair
facilities, but does not include long-term storage or rented manufacturing facilities.
Highest adjacent grade means the highest natural elevation of the ground surface, prior to
construction, adjacent to the proposed foundation of a building.
Historic structure means any structure that is:
(1) Listed individually in the National Register of Historic Places (a listing maintained by the U.S.
Department of Interior) or preliminarily determined by the Secretary of the Interior as meeting
the requirements for individual listing on the National Register:
(2) Certified or preliminarily determined by the Secretary of the interior as contributing to the
historical significance of a registered historic district or a district preliminarily determined by the
Secretary to qualify as a registered historic district:
(3) Individually listed on a state inventory of historic places and determined as eligible by states
with historic preservation programs which have been approved by the Secretary of the Interior;
or
(4) Individually listed on a local inventory of historic places and determined as eligible by
communities with historic preservation programs that have been certified either:
a. By an approved state program as determined by the Secretary of the Interior; or
b. Directly by the Secretary of the Interior in states without approved programs.
Lowest floor means the lowest floor of the lowest enclosed area, including basement. An unfinished
or flood resistant enclosure, used solely for parking of vehicles, building access, or storage, in an area
other than a basement, is not considered a building's lowest floor, provided that such enclosure is not
built so as to render the structure in violation of other provisions of this Code.
Manufactured home means a building, transportable in one or more sections, built on a permanent
chassis and designed to be used with or without a permanent foundation when connected to the required
utilities. The term also includes park trailers, travel trailers, and similar transportable structures placed on
a site for 180 consecutive days or longer and intended to be improved property.
Manufactured home park or subdivision means a parcel (or contiguous parcels) of land divided into
two or more manufactured home lots for rent or sale.
Mean sea level means the average height of the sea for all stages of the tide. It is used as a
reference for establishing various elevations within the floodplain. For purposes of the National Flood
Insurance Program, the North American Vertical Datum (NAVD88), to which base flood elevations shown
on a community's Flood Insurance Rate Map are referenced.
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ARTICLE 8.- FLOOD DAMAGE PREVENTION
DIVISION 1. GENERALLY
National Geodetic Vertical Datum (NGVD) as corrected in 1929 is a vertical control used as a
reference for establishing varying elevations within the floodplain.
New construction means, for purposes of determining insurance rates, structures for which the "start
of construction" commenced after January 14, 1972 [the effective date of the initial FIRM] and includes
any subsequent improvements to such structures. For floodplain management purposes, "new
construction" means structures for which the "start of construction" commenced after November 22, 1972
[the effective date of the first floodplain management ordinance adopted by the community] and includes
any subsequent improvements to such structures.
New manufactured home park or subdivision means a manufactured home park or subdivision for
which the construction of facilities for servicing the lots on which the manufactured homes are to be
affixed (including at a minimum, the installation of utilities, the construction of streets, and either final site
grading or the pouring of concrete pads) is completed on or after November 22, 1972. [i.e., the effective
date of the first floodplain management regulations adopted by a community].
North American Vertical Datum (NAVD) has replaced the National Geodatic Vertical Datum of 1929
in existing and future FEMA floods modernization maps.
Recreational vehicle means a vehicle, which is:
(1) Built on a single chassis;
(2) 400 square feet or less when measured at the largest horizontal projection;
(3) Designed to be self-propelled or permanently towable by a light duty truck; and
(4) Designed primarily not for use as a permanent dwelling but as temporary living quarters for
recreational, camping,travel, or seasonal use.
Start of construction means the date the development permit was issued, provided the actual start of
construction, repair, reconstruction, or improvement was within 180 days of the permit date. The actual
start means the first placement of permanent construction of the structure such as the pouring of slabs or
footings, installation of piles, construction of columns, or any work beyond the stage of excavation, and
includes the placement of a manufactured home on a foundation. (Permanent construction does not
include initial land preparation, such as clearing, grading and filling; nor does it include the installation of
streets and/or walkways; nor does it include excavation for a basement, footings, piers or foundations or
the erection of temporary forms; nor does it include the installation on the property of buildings
appurtenant to the permitted structure, such as garages or sheds not occupied as dwelling units or part of
the main structure. (NOTE: accessory structures are not exempt from any ordinance requirements.) For a
substantial improvement, the actual start of construction means the first alteration of any wall, ceiling,
floor, or other structural part of a building, whether or not that alteration affects the external dimensions of
the building.
Structure means a walled and roofed building that is principally above ground, a manufactured
home, a gas or liquid storage tank.
Subdivision the division of a single lot into two or more lots for the purpose of sale or development.
Substantial damage means damage of any origin sustained by a structure whereby the cost of
restoring the structure to its before damaged condition would equal or exceed fifty (50) percent of the
market value of the structure before the damage occurred.
Substantial improvement means any combination of repairs, reconstruction, alteration, or
improvements to a structure, taking place during a five-year period, in which the cumulative cost equals or
exceeds 50 percent of the market value of the structure before the "start of construction" of the
improvement. NOTE: The market value of the structure should be (1) the appraised value of the structure
Tybee Island, Georgia,Code of Ordinances Page 8
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ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 1. GENERALLY
prior to the start of the initial repair or improvement, or (2) in the case of damage, the value of the
structure prior to the damage occurring. This term includes structures, which have incurred "substantial
damage", regardless of the actual amount of repair work performed. The term does not, however, include
either:
(1) Any project for improvement of a structure to correct existing violations of state or local health,
sanitary, or safety code specifications which have been identified by the local code enforcement
official and which are the minimum necessary to assure safe living conditions; or
(2) Any alteration of a "historic structure" provided that the alteration will not preclude the structure's
continued designation as a "historic structure."
For the purposes of this definition, "substantial improvement" is considered to occur when the first
alteration of any wall, ceiling, floor, or other structural part of the structure commences, whether or not
that alteration affects the external dimensions of the structure.
Substantially improved existing manufactured home parks or subdivisions is where the repair,
reconstruction, rehabilitation or improvement of the streets, utilities and pads equals or exceeds 50
percent of the value of the streets, utilities and pads before the repair, reconstruction or improvement
commenced.
Variance is a grant of relief from the requirements of this ordinance, which permits construction in a
manner otherwise prohibited by this article.
Violation means the failure of a structure or other development to be fully compliant with the
community's floodplain management regulations. A structure or other development without the elevation
certificate, or other certifications, or other evidence of compliance required by this ordinance is presumed
to be in violation until such time as that documentation is provided.
(Ord. of 9-26-2008, Art, 6)
Sec. 8-070. Lands to which this article applies.
This article shall apply to all areas of special flood Hazard within the jurisdiction of Tybee Island,
Georgia.
(Ord. of 9-26-2008, Art. 2, § A)
Sec. 8-080. Basis for area of special flood hazard.
The areas of special flood hazard identified by the Federal Emergency Management Agency (FEMA)
in its Flood Insurance Study (FIS), dated September 26, 2008, with accompanying maps and other
supporting data and any revision thereto, are adopted by reference and declared a part of this article. For
those land areas acquired by a municipality through annexation, the current effective FIS, supporting data
and any revision thereto, for Chatham County, Georgia, dated September 26, 2008 are hereby adopted
by reference.
Areas of special flood hazard may also include those areas known to have flooded historically or
defined through standard engineering analysis by governmental agencies or private parties but not yet
incorporated in a FIS.
The repository for public inspection of the flood insurance study (FIS), accompanying maps and
other supporting data is located: Building and Zoning Department, 403 Butler Avenue, Tybee Island,
Georgia 31328.
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ARTICLE 8.- FLOOD DAMAGE PREVENTION
DIVISION 1. GENERALLY
(Ord. of 9-26-2008, Art. 2, § B)
Sec. 8-090. Establishment of development permit.
A development permit shall be required in conformance with the provisions of this ordinance prior to
the commencement of any development activities.
(Ord. of 9-26-2008, Art. 2, § C)
Sec. 8-100. Compliance.
No structure or land shall hereafter be located, extended, converted or altered without full
compliance with the terms of this ordinance and other applicable regulations,
(Ord. of 9-26-2008, Art. 2, § D)
Sec. 8-110. Abrogation and greater restrictions.
This article is not intended to repeal, abrogate, or impair any existing ordinance, easements,
covenants, or deed restrictions. However, where this ordinance and another conflict or overlap, whichever
imposes the more stringent restrictions shall prevail.
(Ord. of 9-26-2008, Art. 2, § E)
Sec. 8-120. Interpretation.
In the interpretation and application of this ordinance all provisions shall be: (1) considered as
minimum requirements; (2) liberally construed in favor of the governing body, and; (3) deemed neither to
limit nor repeal any other powers granted under state statutes.
(Ord. of 9-26-2008, Art. 2, § F)
Sec. 8-130. Warning and disclaimer of liability.
The degree of flood protection required by this article is considered reasonable for regulatory
purposes and is based on scientific and engineering considerations. Larger floods can and will occur;
flood heights may be increased by man-made or natural causes. This article does not imply that land
outside the areas of special flood Hazard or uses permitted within such areas will be free from flooding or
flood damages. This ordinance shall not create liability on the part of the City of Tybee Island, Georgia or
by any officer or employee thereof for any flood damages that result from reliance on this article or any
administrative decision lawfully made thereunder.
(Ord. of 9-26-2008, Art. 2, § G)
Sec. 8-140. Penalties for violation.
Failure to comply with the provisions of this article or with any of its requirements, including
conditions and safeguards established in connection with grants of variance or special exceptions shall
constitute a violation. Any person who violates this ordinance or fails to comply with any of its
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ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 1. GENERALLY
requirements shall, upon conviction thereof, be fined not more than $1000.00, or imprisoned for not more
than six (6) months, or both, and in addition, shall pay all costs and expenses involved in the case. Each
day such violation continues shall be considered a separate offense. Nothing herein contained shall
prevent the City of Tybee Island, Georgia from taking such other lawful actions as is necessary to prevent
or remedy any violation.
(Ord. of 9-26-2008, Art. 2, § H)
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ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 2.ADMINISTRATION
DIVISION 2. ADMINISTRATION
Sec. 8-150. Designation of ordinance administrator.
Sec. 8-160. Permit procedures.
Sec. 8-170. Duties and responsibilities of the administrator.
Sec. 8-150. Designation of ordinance administrator.
The designated representative of the Building and Zoning Department, Tybee Island, Georgia is
hereby appointed to administer and implement the provisions of this article.
(Ord. of 9-26-2008, Art. 3, § A)
Sec. 8-160. Permit procedures.
Application for a building permit shall be made to the Building and Zoning Department Tybee Island,
Georgia on forms furnished by the community PRIOR to any development activities, and may include, but
not be limited to the following: plans in duplicate drawn to scale showing the elevations of the area in
question and the nature, location, dimensions, of existing or proposed structures, earthen fill placement,
storage of materials or equipment, and drainage facilities.
Specifically, the following information is required:
(1) Application stage:
a. Elevation in relation to mean sea level (or highest adjacent grade) of the lowest floor,
including basement, of all proposed structures;
b. Elevation in relation to mean sea level to which any non-residential structure will be flood-
proofed;
c. Design certification from a registered professional engineer or architect that any proposed
non-residential flood-proofed structure will meet the flood-proofing criteria of subsections 8-
190(2) and 8-210(2);
d. Design certification from a registered professional engineer or architect that any new
construction or substantial improvement placed in a Coastal high hazard area will meet the
criteria of subsection 8-230(5);
e. Description of the extent to which any watercourse will be altered or relocated as a result of
a proposed development; and
(2) Construction stage. For all new construction and substantial improvements, the permit holder
shall provide to the Building and Zoning Department Tybee Island, Georgia an as-built
certification of the regulatory floor elevation or flood-proofing level immediately after the lowest
floor or flood proofing is completed. Where a structure is subject to the provisions applicable to
coastal high hazards areas, after placement of the lowest horizontal structural members. Any
regulatory floor certification made relative to mean sea level shall be prepared by or under the
direct supervision of a registered land surveyor or professional engineer and certified by same.
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DIVISION 2.ADMINISTRATION
When flood proofing is utilized for non-residential structures, said certification shall be prepared
by or under the direct supervision of a professional engineer or architect and certified by same.
Any work undertaken prior to submission of these certifications shall be at the permit holder's
risk.
The city building and zoning department shall review the above referenced certification data
submitted. Deficiencies detected by such review shall be corrected by the permit holder
immediately and prior to further progressive work being allowed to proceed. Failure to submit
certification or failure to make said corrections required hereby, shall be cause to issue a stop-
work order for the project.
(Ord. of 9-26-2008, Art. 3, § B)
Sec. 8-170. Duties and responsibilities of the administrator.
Duties of the Building and Zoning Department Tybee Island, Georgia shall include, but shall not be
limited to:
(1) Review all development permits to assure that the permit requirements of this article have been
satisfied;
(2) Review proposed development to assure that all necessary permits have been received from
governmental agencies from which approval is required by Federal or State law, including
section 404 of the Federal Water Pollution Control Act Amendments of 1972, 33 U.S.C. 1334.
Require that copies of such permits be provided and maintained on file.
(3) Review all permit applications to determine whether proposed building sites will be reasonably
safe from flooding.
(4) When base flood elevation data or floodway data have not been provided in accordance with
section 8-080, then the building and zoning department shall obtain, review and reasonably
utilize any base flood elevation and floodway data available from a federal, state or other
sources in order to administer the provisions of division 3.
(5) Review and record the actual elevation in relation to mean sea level (or highest adjacent grade)
of the regulatory floor, including basement, of all new or substantially improved structures in
accordance with subsection 8-160(2).
(6) Review and record the actual elevation, in relation to mean sea level to which any new or
substantially improved structures have been flood-proofed, in accordance with subsections 8-
190(2) and 8-210(2).
(7) When flood-proofing is utilized for a structure, the building and zoning department shall obtain
certification of design criteria from a registered professional engineer or architect in accordance
with subsection 8-160(1)c. and subsections 8-190(2) and 8-210(2).
(8) Obtain design certification from a registered professional engineer or architect that any new
construction or substantial improvement placed in a coastal high hazard area will meet the
criteria of subsection 8-230(5).
(9) Make substantial damage determinations following a flood event or any other event that causes
damage to structures in flood hazard areas.
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DIVISION 2. ADMINISTRATION
(10) Notify adjacent communities and the Georgia Department of Natural Resources prior to any
alteration or relocation of a watercourse and submit evidence of such notification to the Federal
Emergency Management Agency (FEMA).
(11) For any altered or relocated watercourse, submit engineering data/analysis within six months to
FEMA to ensure accuracy of community flood maps through the Letter of Map Revision
process.Assure flood carrying capacity of any altered or relocated watercourse is maintained.
(12) Where interpretation is needed as to the exact location of boundaries of the areas of special
flood hazard (for example, where there appears to be a conflict between a mapped boundary
and actual field conditions) the city building and zoning department shall make the necessary
interpretation. Any person contesting the location of the boundary shall be given a reasonable
opportunity to appeal the interpretation as provided in this article.
(13) All records pertaining to the provisions of this article shall be maintained in the office of the
Building and Zoning Department 403 Butler Ave. Tybee Island, Georgia, and shall be open for
public inspection.
(Ord. of 9-26-2008, Art. 3, § C)
Tybee Island, Georgia, Code of Ordinances Page 14
PART II -CODE OF ORDINANCES
APPENDIX A- LAND DEVELOPMENT CODE
ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 3. PROVISIONS FOR FLOOD HAZARD REDUCTION
DIVISION a PROVISIONS FOR FLOOD HAZARD REDUCTION
Sec. 8-180. General standards.
Sec. 8-190. Specific standards.
Sec. 8-200. Building standards for streams without established base flood elevations and/or floodwav (A-
zones).
Sec. 8-210. Standards for areas of special flood hazard (zones AE) with established base flood elevations
without designated floodways.
Sec. 8-220. Standards for areas of shallow flooding (AO zones).
Sec. 8-230. Coastal high hazard areas (V-zones).
Sec. 8-240. Standards for subdivisions.
Sec. 8-250. Standard for critical facilities.
Sec. 8-180. General standards.
In all areas of special flood hazard the following provisions are required:
(1) New construction and substantial improvements of existing structures shall be anchored to
prevent flotation, collapse or lateral movement of the structure;
(2) New construction and substantial improvements of existing structures shall be constructed with
materials and utility equipment resistant to flood damage;
(3) New construction or substantial improvements of existing structures shall be constructed by
methods and practices that minimize flood damage;
(4) Elevated Buildings. All New construction or substantial improvements of existing structures that
include ANY fully enclosed area located below the lowest floor formed by foundation and other
exterior walls shall be designed so as to be an unfinished or flood resistant enclosure. The
enclosure shall be designed to equalize hydrostatic flood forces on exterior walls by allowing for
the automatic entry and exit of floodwater. (not applicable in coastal high hazard areas).
a. Designs for complying with this requirement must either be certified by a professional
engineer or architect or meet the following minimum criteria:
1. Provide a minimum of two openings having a total net area of not less than one
square inch for every square foot of enclosed area subject to flooding;
2. The bottom of all openings shall be no higher than one foot above grade; and
3. Openings may be equipped with screens, louvers, valves or other coverings or
devices provided they permit the automatic flow of floodwater in both directions.
b. So as not to violate the "lowest floor" criteria of this article, the unfinished or flood resistant
enclosure shall only be used for parking of vehicles, limited storage of maintenance
equipment used in connection with the premises, or entry to the elevated area; and
c. The interior portion of such enclosed area shall not be partitioned or finished into separate
rooms.
Tybee Island, Georgia,Code of Ordinances Page 15
PART II -CODE OF ORDINANCES
APPENDIX A- LAND DEVELOPMENT CODE
ARTICLE 8.- FLOOD DAMAGE PREVENTION
DIVISION 3. PROVISIONS FOR FLOOD HAZARD REDUCTION
(5) All heating and air conditioning equipment and components (including ductwork), all electrical,
ventilation, plumbing fixtures, and other service facilities shall be designed and/or located so as
to prevent water from entering or accumulating within the components during conditions of
flooding.
(6) Manufactured homes shall be anchored to prevent flotation, collapse, or lateral movement.
Methods of anchoring may include, but are not limited to, use of over-the-top or frame ties to
ground anchors. This standard shall be in addition to and consistent with applicable State
requirements for resisting wind forces.
(7) New and replacement water supply systems shall be designed to minimize or eliminate
infiltration of flood waters into the system;
(8) New and replacement sanitary sewage systems shall be designed to minimize or eliminate
infiltration of flood waters into the systems and discharges from the systems into flood waters;
(9) On-site waste disposal systems shall be located and constructed to avoid impairment to them or
contamination from them during flooding, and;
(10) Any alteration, repair, reconstruction or improvement to a structure, which is not compliant with
the provisions of this article, shall be undertaken only if the non-conformity is not furthered,
extended or replaced.
(Ord. of 9-26-2008, Art. 4, § A)
Sec. 8-190. Specific standards.
In all areas of special flood hazard designated as A1-30, AE, AH, A (with estimated BFE), the
following provisions are required:
(1) New construction and/or substantial improvements. Where base flood elevation data are
available, new construction and/or substantial improvement of any structure or manufactured
home shall have the lowest floor, including basement, elevated no lower than one foot I
two foot 1 three foot above the base flood elevation. Should solid foundation perimeter
walls be used to elevate a structure, openings sufficient to facilitate the unimpeded movements
of flood waters shall be provided in accordance with standards of subsection 8-180(4),
"Elevated Buildings."
a. All heating and air conditioning equipment and components (including ductwork), all
electrical, ventilation, plumbing fixtures and other service facilities shall be elevated at or
above one foot / two foot I three foot above the base flood elevation.
(2) Non-residential construction. New construction and/or the substantial improvement of any
structure located in A1-30, AE, or AH zones, may be flood-proofed in lieu of elevation. The
structure, together with attendant utility and sanitary facilities, must be designed to be water
tight to one foot I two foot 1 three foot above the base flood elevation, with walls
substantially impermeable to the passage of water, and structural components having the
capability of resisting hydrostatic and hydrodynamic loads and the effect of buoyancy. A
registered professional engineer or architect shall certify that the design and methods of
construction are in accordance with accepted standards of practice for meeting the provisions
above, and shall provide such certification to the official as set forth above and in subsection 8-
170(6).
Tybee Island, Georgia, Code of Ordinances Page 16
PART II -CODE OF ORDINANCES
APPENDIX A- LAND DEVELOPMENT CODE
ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 3. PROVISIONS FOR FLOOD HAZARD REDUCTION
(3) Standards for manufactured homes and recreational vehicles—Where base flood elevation data
are available:
a. All manufactured homes placed and/or substantially improved on: (1) individual lots or
parcels, (2) in new and/or substantially improved manufactured home parks or
subdivisions, (3) in expansions to existing manufactured home parks or subdivisions, or (4)
on a site in an existing manufactured home park or subdivision where a manufactured
home has incurred "substantial damage" as the result of a flood, must have the lowest floor
including basement, elevated no lower than one foot I two foot I three foot
above the base flood elevation.
b. Manufactured homes placed and/or substantially improved in an either existing
manufactured home park or subdivision may be elevated so that:
1. The lowest floor of the manufactured home is elevated no lower than one foot I
two foot I three foot above the level of the base flood elevation; or
2. The manufactured home chassis is elevated and supported by reinforced piers (or
other foundation elements of at least an equivalent strength) of no less than 36 inches
in height above grade.
c. All manufactured homes must be securely anchored to an adequately anchored foundation
system to resist flotation, collapse and lateral movement. (ref. subsection 8-180(6) above)
d. All recreational vehicles placed on sites must either;
1. Be on the site for fewer than 180 consecutive days;
2. Be fully licensed and ready for highway use, (a recreational vehicle is ready for
highway use if it is licensed, on its wheels or jacking system, attached to the site only
by quick disconnect type utilities and security devices, and has no permanently
attached structures or additions); or
3. The recreational vehicle must meet all the requirements for "New Construction",
including the anchoring and elevation requirements of subsections (3)a. and c.,
above.
(4) Floodway. Located within areas of special flood Hazard established in section 8-080 are areas
designated as floodway. A floodway may be an extremely hazardous area due to velocity
floodwaters, debris or erosion potential. In addition, the area must remain free of encroachment
in order to allow for the discharge of the base flood without increased flood heights. Therefore,
the following provisions shall apply:
a. Encroachments are prohibited, including earthen fill, new construction, substantial
improvements or other development within the regulatory floodway. Development may be
permitted however, provided it is demonstrated through hydrologic and hydraulic analyses
performed in accordance with standard engineering practice that the encroachment shall
not result in any increase in flood levels or floodway widths during a base flood discharge.
A registered professional engineer must provide supporting technical data and certification
thereof.
b. Only if subsection (4)a. above is satisfied, then any new construction or substantial
improvement shall comply with all other applicable flood hazard reduction provisions of this
division.
(Ord. of 9-26-2008, Art. 4, § B)
Tybee Island, Georgia,Code of Ordinances Page 17
PART II -CODE OF ORDINANCES
APPENDIX A- LAND DEVELOPMENT CODE
ARTICLE 8.- FLOOD DAMAGE PREVENTION
DIVISION 3. PROVISIONS FOR FLOOD HAZARD REDUCTION
Sec. 8-200. Building standards for streams without established base flood elevations
and/or floodway (A-zones).
Located within the areas of special flood hazard established in section 8-080, where streams exist
but no base flood data have been provided (A-zones), or where base flood data have been provided but a
Floodway has not been delineated, the following provisions apply:
(1) When base flood elevation data or floodway data have not been provided in accordance with
section 8-080), then the building and zoning department shall obtain, review, and reasonably
utilize any scientific or historic base flood elevation and floodway data available from a federal,
state, or other source, in order to administer the provisions of this division. Only if data are not
available from these sources, then the following provisions (subsections (2) and (3)) shall apply:
(2) No encroachments, including structures or fill material, shall be located within an area equal to
the width of the stream or 25 feet, whichever is greater, measured from the top of the stream
bank, unless certification by a registered professional engineer is provided demonstrating that
such encroachment shall not result in more than one foot increase in flood levels during the
occurrence of the base flood discharge.
(3) In special flood hazard areas without base flood elevation data, new construction and
substantial improvements of existing structures shall have the lowest floor of the lowest
enclosed area (including basement) elevated no less than three feet above the highest adjacent
grade at the building site. (NOTE: Require the lowest floor to be elevated one foot / two
foot / three foot above the estimated base flood elevation in A-Zone areas where a
limited detail study has been completed). Openings sufficient to facilitate the unimpeded
movements of floodwaters shall be provided in accordance with standards of subsection 8-
1 80(4), "Elevated buildings."
a. All heating and air conditioning equipment and components (including ductwork), all
electrical, ventilation, plumbing fixtures, and other service facilities shall be elevated no
less than three feet above the highest adjacent grade at the building site.
The Building and Zoning Department shall certify the lowest floor elevation level and the
record shall become a permanent part of the permit file.
(Ord. of 9-26-2008, Art. 4, § C)
Sec. 8-210. Standards for areas of special flood hazard (zones AE) with established base
flood elevations without designated floodways.
Located within the areas of special flood hazard established in section 8-080, where streams with
base flood elevations are provided but no floodways have been designated, (Zones AE) the following
provisions apply:
(1) No encroachments, including fill material, new structures or substantial improvements shall be
located within areas of special flood hazard, unless certification by a registered professional
engineer is provided demonstrating that the cumulative effect of the proposed development,
when combined with all other existing and anticipated development, will not increase the water
surface elevation of the base flood more than one foot at any point within the community. The
engineering certification should be supported by technical data that conforms to standard
hydraulic engineering principles.
Tybee Island, Georgia, Code of Ordinances Page 18
PART II -CODE OF ORDINANCES
APPENDIX A- LAND DEVELOPMENT CODE
ARTICLE 8. - FLOOD DAMAGE PREVENTION
DIVISION 3, PROVISIONS FOR FLOOD HAZARD REDUCTION
(2) New construction or substantial improvements of buildings shall be elevated or flood-proofed to
elevations established in accordance with section 8-190
(Ord. of 9-26-2008, Art. 4, § D)
Sec. 8-220. Standards for areas of shallow flooding (AO zones).
Areas of special flood hazard established in Section 8-080, may include designated "AO" shallow
flooding areas. These areas have base flood depths of one to three feet above ground, with no clearly
defined channel. The following provisions apply:
(1) All new construction and substantial improvements of residential and non-residential structures
shall have the lowest floor, including basement, elevated to the flood depth number specified on
the flood insurance rate Map (FIRM), above the highest adjacent grade. If no flood depth
number is specified, the lowest floor, including basement, shall be elevated at least three feet
above the highest adjacent grade. Openings sufficient to facilitate the unimpeded movements of
flood waters shall be provided in accordance with standards of subsection 8-180(4), "Elevated
buildings".
The surveyor, architect, or engineer shall certify the lowest floor elevation level and the record
shall become a permanent part of the permit file.
(2) New construction or the substantial improvement of a non-residential structure may be flood-
proofed in lieu of elevation. The structure, together with attendant utility and sanitary facilities,
must be designed to be water tight to the specified FIRM flood level plus one foot / two
foot I three foot, above highest adjacent grade, with walls substantially impermeable to
the passage of water, and structural components having the capability of resisting hydrostatic
and hydrodynamic loads and the effect of buoyancy. A registered professional engineer or
architect shall certify that the design and methods of construction are in accordance with
accepted standards of practice for meeting the provisions above, and shall provide such
certification to the official as set forth above and as required in subsections 8-160(1)c. and (2).
(3) Drainage paths shall be provided to guide floodwater around and away from any proposed
structure.
(Ord. of 9-26-2008, Art. 4, § E)
Sec. 8-230. Coastal high hazard areas (V-zones).
Located within the areas of special flood hazard established in Section 8-080, are areas designated
as coastal high hazard areas (V-zones). These areas have special flood hazards associated with wave
action and storm surge, therefore, the following provisions shall apply:
(1) All new construction and substantial improvements of existing structures shall be located
landward of the reach of mean high tide;
(2) All new construction and substantial improvements of existing structures shall be elevated on
piles, columns, or shear walls parallel to the flow of water so that the bottom of the lowest
supporting horizontal structural member (excluding pilings or columns) is located no lower than
one foot / two foot I three foot above the base flood elevation level. All space
below the lowest supporting member shall remain free of obstruction or constructed with non-
supporting breakaway walls. Open wood lattice work or decorative screening may be permitted
Tybee Island, Georgia, Code of Ordinances Page 19
PART II -CODE OF ORDINANCES
APPENDIX A- LAND DEVELOPMENT CODE
ARTICLE 8.- FLOOD DAMAGE PREVENTION
DIVISION 3. PROVISIONS FOR FLOOD HAZARD REDUCTION
for aesthetic purposes only and must be designed to wash away in the event of abnormal wave
action and in accordance with subsection below;
(3) All new construction and substantial improvements of existing structures shall be securely
anchored on pilings, columns, or shear walls; and
(4) All pile and column foundations and the structures attached thereto shall be anchored to resist
flotation, collapse, and lateral movement due to the combined effects of wind and water loads
acting simultaneously on ALL building components, both (non-structural and structural). Water
loading values shall equal or exceed those of the base flood. Wind loading values shall be in
accordance with the most current edition of the (ICC) International Building Codes.
(5) A registered professional engineer or architect shall certify that the design, specifications and
plans for construction are in compliance with the provisions contained in subsection (2) through
(4) herein.
(6) All space below the lowest horizontal supporting member must remain free of obstruction. Open
wood lattice work or decorative screening may be permitted for aesthetic purposes only and
must be designed to wash away in the event of abnormal wave action without causing structural
damage to the supporting foundation or elevated portion of the structure. The following design
specifications are allowed:
a. No solid walls shall be allowed; and
b. Material shall consist of open wood lattice or mesh screening only.
c. If aesthetic open wood lattice work or screening is utilized, any enclosed space shall not be
used for human habitation, but shall be designed to be used only for parking of vehicles,
building access, or limited storage of maintenance equipment used in connection with the
premises.
(7) Prior to construction, plans for any structures having open wood latticework or decorative
screening must be shown on the plans submitted to the city building and zoning department for
review and approval;
(8) Any alteration, repair, reconstruction or improvement to any structure shall not enclose the
space below the lowest floor except with open wood latticework or decorative screening, as
provided in this section.
(9) There shall be no fill used as structural support. Non-compacted fill may be used around the
perimeter of a building for landscaping/aesthetic purposes provided the fill will wash out from
storm surge, (thereby rendering the building free of obstruction) prior to generating excessive
loading forces, ramping effects, or wave deflection. The building and zoning department shall
approve design plans for landscaping/aesthetic fill only after the applicant has provided an
analysis by an engineer, architect, and/or soil scientist, which demonstrates that the following
factors have been fully considered:
a. Particle composition of fill material does not have a tendency for excessive natural
compaction;
b. Volume and distribution of fill will not cause wave defection to adjacent properties; and
c. Slope of fill will not cause wave run-up or ramping.
(10) There shall be no alteration of sand dunes or mangrove stands, which would increase potential
flood damage;
Tybee Island, Georgia, Code of Ordinances Page 20
PART II -CODE OF ORDINANCES
APPENDIX A- LAND DEVELOPMENT CODE
ARTICLE 8.- FLOOD DAMAGE PREVENTION
DIVISION 3. PROVISIONS FOR FLOOD HAZARD REDUCTION
(11) Prohibit the placement of manufactured homes (mobile homes), except in an existing
manufactured homes park or subdivision. A replacement manufactured home may be placed on
a lot in an existing manufactured home park or subdivision provided the anchoring standards of
subsection 8-190(3) are met.
(Ord. of 9-26-2008, Art. 4, § F)
Sec. 8-240. Standards for subdivisions.
(A) All subdivision and/or development proposals shall be consistent with the need to minimize flood
damage;
(B) All subdivision and/or development proposals shall have public utilities and facilities such as sewer,
gas, electrical and water systems located and constructed to minimize flood damage;
(C) All subdivision and/or development proposals shall have adequate drainage provided to reduce
exposure to flood hazards, and;
(D) For subdivisions and/or developments greater than 50 lots or five acres, whichever is less, base
flood elevation data shall be provided for subdivision and all other proposed development, including
manufactured home parks and subdivisions. Any changes or revisions to the flood data adopted
herein and shown on the FIRM shall be submitted to FEMA for review as a conditional letter of map
revision (CLOMR) or conditional letter of map amendment (CLOMA), whichever is applicable. Upon
completion of the project, the developer is responsible for submitting the "as-built" data to FEMA in
order to obtain the final LOMR.
(Ord. of 9-26-2008, Art. 4, § G)
Sec. 8-250. Standard for critical facilities.
(a) Critical facilities shall be elevated to or above the 100-year floodplain or the 500-year floodplain.
(B) All ingress and egress from any critical facility must be protected to the 500-year flood elevation.
(Ord. of 9-26-2008, Art. 4, § H)
Tybee Island, Georgia, Code of Ordinances Page 21
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National Flood Insurance Program
Community Rating System
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Glossary
Floodway: The channel of a river and the portion of the overbank floodplain that must be
reserved in order to discharge the base flood without cumulatively increasing the water
surface elevation by a designated height. The National Flood Insurance Program
regulations allow construction in the floodway provided that it does not obstruct flood
flows or increase flood heights.
Floodway fringe: The portion of the Special Flood Hazard Area lying outside of the
floodway.
Freeboard: A margin of safety added to the base flood elevation to account for waves,
debris, miscalculations, lack of data, or changes in climate.
Green infrastructure: Because of the wide interpretation given to this term, the CRS does
not use the words "green infrastructure" in its credit criteria. However, the CRS does
provide credit for designated open space corridors or connected networks of wetlands,
woodlands, wildlife habitats, wilderness, and other areas that support native species,
maintain natural ecological processes, and sustain air and water resources. In some areas,
these features are called "green infrastructure."
High-hazard-potential dam: Dams assigned the high-hazard-potential classification are
those whose failure or mismanagement will probably cause loss of human life.
Hydrology: The science dealing with the waters of the earth. A flood discharge is
developed by a hydrologic study.
I-Codes: The series of building codes published by the International Code Council.
ICC: Increased Cost of Compliance coverage, a flood insurance claim provision that helps
fund the cost of bringing a flood-damaged building into compliance with floodplain
management standards.
ISO: The Insurance Services Office, Inc., a corporation that conducts verification of
community CRS credit and program improvement tasks for FEMA.
ISO/CRS Specialist: An Insurance Services Office, Inc. technician responsible for
reviewing community requests for Community Rating System classification and verifying
implementation of activities credited by the CRS. The name and telephone number of the
ISO/CRS Specialist for a state can be found at www.CRSresources.org/100.
ISO/CRS Technical Reviewer: An Insurance Services Office, Inc. technician or
contractor responsible for reviewing community requests for Community Rating System
credit for select activities. The reviews conducted by the ISO/CRS Technical Reviewer are
provided to the ISO/CRS Specialist.
Levee: A manmade structure, usually an earthen embankment, designed and constructed
using sound engineering practices to contain, control, or divert flood waters in accordance
with a designated risk reduction level.
CPS Coordinator's Manual 120-5 Edition: 2013
4
Higher Regulatory Standards
430 HIGHER REGULATORY STANDARDS
The OBJECTIVE of this activity is to credit regulations to protect existing and future
development and natural floodplain functions that exceed the minimum criteria of the
National Flood Insurance Program (NFIP).
431 Background
Current NFIP standards for regulation of development in
riverine areas require that new residential buildings in the A separate publication, CRS
Special Flood Hazard Area (SFHA) have their lowest Credit for Higher Regulatory
floor at or above the base flood elevation. Non-residential Standards, provides additional
buildings may be floodproofed to the base flood elevation. information on the elements credi-
NFIP coastal rules require that new buildings be above the ted here, including example ordi-
base flood elevation and, in V (velocity) Zones, be built nance language and documenta-
on engineered piles or columns. If an existing building is tion. Communities are encouraged
improved or reconstructed and the value of the project to obtain and read the document
exceeds 50% of the building's value, the building must be before applying for this activity.
brought up to the same standards applied to new To order a free copy, see
construction. Appendix C or
www.CRSresources.org/400.
Although the NFIP minimum standards provide a great
deal of flood protection, damage can still result for many E
reasons:
• Estimates of flood heights are subject to various errors and may be low, especially in
areas without long-term flood and rainfall records;
• Buildings may be damaged by floods that exceed the predicted 100-year flood;
• Urbanization and other changes in the watershed can increase the flood hazard and
flood frequency;
• Filling and other development in the floodplain can reduce storage and conveyance
capacity; and
• Filling and construction practices can damage or destroy valuable natural floodplain
functions.
For these reasons, and the fact that local situations vary, many communities adopt
development standards that are higher than or supplement the minimum NFIP criteria. This
activity provides credit for those regulatory standards.
24
CRS Coordinator's Manual 430-2 Edition: 2013
Higher Regulatory Standards
431.a. Activity Description
Under this activity, numerous higher regulatory approaches are credited that provide more
protection to new development, redevelopment, and existing development. Examples of
higher standards and the benefits that they can provide include
• Prohibiting fill and other ground-altering measures can protect existing development
and habitat, improve water quality, and maintain the flood attenuating benefits of
natural areas (credited under DL1a);
• Requiring compensatory storage preserves areas of the floodplain that can store flood
water and minimizes increases in flood heights due to development (credited under
DL1b);
• Requiring the lowest floors of residences to be higher than the base flood elevation
protects buildings from higher floods (credited under FRB);
• Protecting foundations reduces damage that results from scour and settling (credited
under FDN);
• Requiring full compliance with floodplain management regulations when proposed
improvements or repairs are less than 50% of a building's value brings more
nonconforming buildings up to current flood protection standards (credited under CSI
and LSI);
• Protecting critical facilities to higher levels reduces damage to those facilities and
improves the community's ability to respond to the needs of citizens during a disaster
(credited under PCF);
• Adopting and enforcing a building code improves the quality of construction of new
buildings and provides more staff support for floodplain management regulations
(credited under BC);
• Standards for protecting buildings from local drainage problems reduce flood losses
and flood insurance claims, especially outside the floodplain (credited under LDP);
• Requiring new manufactured housing in existing manufactured housing parks to meet
the same level of protection as is required for other new buildings reduces flood
losses and flood insurance claims (credited under MHP);
• Requiring new construction in the coastal A Zone to meet the same standards as V-
Zone buildings protects it from a known, but unmapped, breaking wave hazard
(credited under CAZ);
• Adopting and enforcing construction rules tailored to special flood-related hazards,
such as coastal erosion and alluvial fan flooding, provides protection in ways that the
NFIP's national minimum criteria cannot do (credited under SHR); and
• Having Certified Floodplain Managers (CFMe) and high-quality administrative
procedures and inspections can reduce errors and minimize problems during
construction (credited under RA).
25-
CRS Coordinator's Manual 430-3 Edition: 2013
Higher Regulatory Standards
The element OHS (other higher standards), provides credit for regulations not listed in this
or other activities. As noted in Section 113.d, communities are invited and encouraged to
submit other regulatory provisions that are not part of the NFIP's minimum criteria and/or
alternative approaches to the credits listed here.
NOTE: A community should not amend its ordinances solely to earn Community Rating
System (CRS) credit points, nor should it necessarily adopt the examples used in the CRS
Coordinator's Manual. Ordinance language should be carefully written to support the
community's own goals and the purposes of its regulatory program. All such language
should be reviewed by the community's legal counsel before it is adopted.
431.b. Activity Credit Criteria
For all the elements except RA (regulations administration, Section 431.o), the community
must provide a legally enforceable regulation. In most cases, this will be in the form of an
ordinance adopted by the community's governing body.
(1) Regulations adopted by a county, regional agency, or state that are enforced within the
community can be credited. Their implementation is verified in the same manner as a
community regulation and it is expected that the community will assist in the
verification. See also Section 231.d on uniform minimum credit.
(2) Regulations must have the force of law and meet the requirement of Section 231.b.
(3) If the legal authority for the regulatory language is not clear, the ISO/CRS Specialist
may request a letter from the community's legal counsel that confirms that he/she will
defend the regulation in court if it is challenged.
(4) For CRS credit, the regulatory language must be adopted and in full force at the time
CRS credit is requested, e.g., at the verification visit.
(5) Credit for any element is prorated if the sampling done during verification finds
instances in which the element is not fully implemented. It does not matter why it is not
fully implemented. For example, if a review of Elevation Certificates finds that some
new buildings did not have the required freeboard because of legally issued variances,
the credit is still prorated.
See also Section 231 on documentation of regulations for CRS credit.
431.c. Activity Impact Adjustment
Impact adjustment ratios are part of the calculations for all elements in Activity 430 except
BC, LDP, MHP, SMS, and RA. They are explained in Sections 402-403.
(1) An impact adjustment map must be prepared when
(a) The acreage or square mileage of the areas qualifying for Activity 430 credit needs
to be determined for the impact adjustment ratio, or
CRS Coordinator's Manual 430-4 Edition: 2013
Higher Regulatory Standards
(b) The regulations are enforced outside the SFHA so that the impact adjustment ratio
can be greater than 1.0. If the impact adjustment ratio is greater than 1.0, the
community will receive more points than the maximum listed for the element. The
maximum ratio for this is 1.5 (i.e., the area regulated is 50% (or more) larger than
the SFHA).
(2) The areas affected by the regulation(s) must be marked on an impact adjustment map.
Marking each area with the appropriate acronym is a convenient shorthand. Section 402
has additional information about determining impact adjustments for areas.
(3)Areas to be credited for a higher regulatory standard must not include areas preserved as
open space (OSP) in Activity 420 (Open Space Preservation). Therefore, OSP credited
areas must be shown on the impact adjustment map used for Activity 430. There is no
Activity 430 credit for higher standards for fill or buildings in areas where fill and
buildings are not allowed (i.e., areas preserved as open space). This is explained in
Section 402.c.
(4) An impact adjustment map does not need to be prepared when a regulatory standard is
enforced throughout the entire SFHA. The impact adjustment ratio in that case is 1.0.
However, the community must be certain that a regulation is enforced throughout the
regulatory floodplain. For example, the ordinance may say that all new buildings must
be built to a freeboard level, but that rule may only apply in flood zones where a base
flood elevation is provided. In such cases, an impact adjustment map would be needed
to delineate and calculate the areas affected by the freeboard standard.
(5) An impact adjustment map does not need to be prepared when a regulatory standard is
enforced throughout the entire SFHA, but the community is receiving credit for
preserving open space (OSP) in Activity 420 (Open Space Preservation). If the only
adjustment to the impact of an element is for OSP, the impact adjustment ratio for the
430 element is the complement of the impact adjustment for OSP.
Example 431.c-1.
A community has 22% of its SFHA preserved as open space.
rOSP = 0.22. The community enforces its freeboard requirement
throughout the rest of the SFHA.
rFRB = 1 — rOSP = 1 — 0.22 = 0.78
There is no need for a separate impact adjustment map for Activity 430
in this instance.
(6) If less than 10% of the community's SFHA is affected by the regulations or if the
community does not prepare an impact adjustment map, an impact adjustment ratio of
0.1 can be used (up to 0.5 for CAZ).
2.1
CRS Coordinator's Manual 430-5 Edition: 2013
Higher Regulatory Standards
Sections 402-403 provide guidance on impact adjustments and impact adjustment maps.
Additional criteria and clarifications may be included under each activity's impact
adjustment section.
The community's aSFHA should be reviewed and updated each year for the Program Data
Table that is included in the annual recertification (see Section 213.a).
431.d. Activity Documentation Provided by the Community
Most elements in this activity have the same documentation needs at the verification visit:
(1) The state or local law or ordinance language that adopts the regulatory standard. See
also Sections 231.b and 231.c on documenting regulatory language.
(2) The impact adjustment map. See Section 431.c.
(3) [For credit for regulating flood-prone areas outside the SFHA] Documentation that
shows that regulations are in effect outside the SFHA (i.e., the regulatory floodplain).
(4) Development plans and/or permit records that document how the regulation has been
applied.
The ISO/CRS Specialist may visit a sample of sites in the field to verify that the land has
been developed and/or buildings have been constructed in accordance with the approved
plans.
Some elements have additional or different documentation requirements, as noted in the
separate documentation sections, below.
432 Elements
432.a. Development limitations (DL)
The maximum credit for this element is 1,330 points.
This element has three parts, crediting different aspects of the regulation of floodplain
development:
(1) Prohibition of fill (DI,1) (maximum credit: 280 points). The use of fill to elevate
buildings has advantages that make it desirable for developers and homeowners.
However, there are problems with using fill: it reduces floodplain storage capacity and
it has an adverse impact on native vegetation, wetlands, drainage, and water quality.
All of the benefits of using fill accrue to the developer and to the property owner.
Conversely, all of the problems accrue to neighbors, taxpayers, the community, the
NFIP, or the environment. Because filling is therefore not a desirable floodplain
management activity, this element credits communities that prohibit fill.
CRS Coordinator's Manual 430-6 Edition: 2013
Higher Regulatory Standards
One method to offset the impacts of the use of fill is to require compensatory storage,
but compensatory storage does not compensate for the adverse impact on other natural
floodplain functions. Therefore, it is worth approximately half the credit. This credit is
for regulations that require new developments to provide compensatory storage at
hydraulically equivalent sites up to a ratio of 1.5 to 1.
(2) Prohibition of buildings (DL2) (maximum credit: 1,000 points). If the regulations
prohibit only certain types of buildings, such as residences, the points can be prorated.
(3) Prohibition of outdoor storage of materials (DL3) (maximum credit: 50 points). Credit
can be received under three sub-elements:
(a) Prohibition of all materials (DL3a): Full credit for DL3 is for prohibiting outdoor
storage of all materials in the SFHA.
(b) Prohibition of hazardous materials (DL3b): Partial credit is provided if only
hazardous materials are prohibited (indoors or outdoors).
(c) Storage of hazardous materials (DL3c): Credit is provided if hazardous materials are
allowed to be stored indoors in the floodplain, but must be elevated above the base
flood elevation.
If all three items (DL1, DL2, and DL3) are included in the community's regulations and
there are still vacant areas in the regulatory floodplain, those areas would be effectively
preserved as open space. The community should submit those areas for the higher credit for
OSP in Activity 420 (Open Space Preservation). See Section 422.a(3)(c).
These regulations have their full impact in undeveloped areas. Therefore, the impact
adjustment map must identify areas credited for open space preservation (OSP) and areas
that are undeveloped, i.e., where there are no buildings on the parcels or the area is zoned
for conservation or agriculture with a minimum lot size of 10 acres or larger.
Credit Criteria
(1) Prohibition of fill (DL1):
(a) Prohibition of all fill (DL1a): This credit is for prohibiting all filling in the
regulatory floodplain.
This includes not approving Conditional Letters or Letters of Map Revision based on
Fill (CLOMR-F or LOMR-F). When a CLOMR-F or LOMR-F is applied for, the
community is required by the Federal Emergency Management Agency (FEMA) to
sign a Community Acknowledgment Form that states, in part, "the completed or
proposed project meets or is designed to meet all of the community floodplain
management requirements . . ." If a CLOMR-F or LOMR-F is issued for a property
in the community, then DL1 credit will be denied. This applies to CLOMRs and
LOMRs that include filling as part of the reason for requesting a map change.
Filling may be allowed where needed to protect or restore natural floodplain
functions, such as a part of a channel restoration project.
CRS Coordinator's Manual 430-7 Edition: 2013
Higher Regulatory Standards
The following regulatory approaches do not warrant credit for DL1:
• Regulations that prohibit loss of storage only if it adversely affects flood
heights on other properties. This credit is for prohibiting all filling, particularly
because of its adverse effect on natural floodplain functions.
• Subdivision regulations that do not apply to all new development.
• Regulations that apply to buildings or private development, but not to bridges,
highways, parking lots, and other floodplain uses.
• The standard NFIP language that prohibits increases in flood heights in
floodways. That standard does not prohibit fill—it allows filling that can be
shown by an engineering study not to increase flood levels. It reads
Prohibit encroachments,including fill,new construction, substantial
improvements and other developments unless certification(with
supporting technical data)by a registered professional engineer is
provided demonstrating that encroachments shall not result in any
increase in flood levels during occurrence of the base flood discharge; , , .
(b) Compensatory storage (DL1b): This credit is for regulations that require new
development to provide compensatory storage at hydraulically equivalent sites up to
a ratio of 1.5:1. Credit is not provided for
• Compensatory storage requirements in floodways only or in V Zones only, or
• Stormwater management regulations that require a developer to compensate for
any increase in runoff created by the development.
(2) Prohibition of buildings (DL2): Full credit for DL2 is for prohibiting all new buildings
in the SFHA. If the regulations only prohibit certain types of buildings, such as
residences, the points will be prorated. If buildings are prohibited in parts of the SFHA,
such as the floodway, the impact adjustment will adjust the points. Prohibiting critical
facilities is credited in Section 432,f, Protection of critical facilities, not under DL2.
(3) Prohibitions on storage of materials (DL3) has no additional criteria.
Credit Points
(1) DL1 = EITHER:
(a) 280 points, for regulations that prohibit fill within floodplains,
including construction of buildings on fill,
OR
(b) 130 points x the ratio of compensation, for regulations that
require new development to provide compensatory
storage at hydraulically equivalent sites up to a maximum of
195 for a ratio of 1.5:1 or greater
CRS Coordinator's Manual 430-8 Edition: 2013
Higher Regulatory Standards
Example 432.a-1.
A community requires that for each cubic foot of fill placed in the
regulatory floodplain, the builder must remove a cubic foot of fill from a
hydraulically equivalent location. The compensation ratio is 1:1, so
DL1b = 130x1 = 130.
Gulf Beach County requires that for each cubic foot of fill placed in the
regulatory floodplain, the builder must remove 1.25 cubic feet of fill
from a hydraulically equivalent location. The compensation ratio is
1.25:1, so DL1b = 130 x 1.25 = 162.5.
(2) DL2 = 1,000 points, for regulations that prohibit buildings within
the regulatory floodplain
If the regulations only prohibit certain types of buildings, such as residences, the points will
be prorated.
(3) DL3 = one of the following:
(a) 50 points, for regulations that prohibit outdoor storage of
materials within the regulatory floodplain,
OR
(b) 20 points, for regulations that prohibit storage of hazardous
materials anywhere in the floodplain,
OR
(c) 10 points, for regulations that require hazardous materials to
be stored indoors, above the base flood elevation
DL3 credit is not cumulative. If the regulations govern storage of only certain kinds of
materials, the points will be prorated.
Impact Adjustment
DL credit is adjusted based on the ratio of the area affected by the DL regulation to the area
of the SFHA. See Section 431.c on calculating an impact adjustment. The following
additional criteria apply:
(1) The areas affected by the DL regulation(s) must be marked on an impact adjustment
map that meets the criteria in Section 431.c. In addition to showing areas credited under
OSP, the map must also show developed and undeveloped areas. "Undeveloped" means
CRS Coordinator's Manual 430-9 Edition: 2013
Higher Regulatory Standards
that there are no buildings on the parcels or that the area is zoned for conservation or
agriculture with a minimum lot size of 10 acres (these areas may also qualify for LZ
credit).
(2) Areas credited for DL credit must exclude areas credited for OSP. However, if the DL
regulations are sufficient, vacant areas may qualify for OSP and the community should
receive the higher points under OSP (see Section 422.a(3)(c)).
(3) Only undeveloped areas are eligible for DL1a and DL2 credit, unless the regulations
clearly state that they apply to developed areas. For example, if DL2 regulations are
enforced in areas already developed and a building is substantially damaged, it cannot
be replaced and the site must be cleared and kept vacant. Note that if a DL2 regulation
prohibits all new buildings except farm structures, the value for DL2 can be prorated
and the credit can be applied to areas with farm structures.
(4) DL lb, compensatory storage, and DL3, prohibitions on storage of materials, can be
credited in developed areas.
rDL# = aDL# , where
aSFHA
aDL# = the size of the area(s) that qualify for DL# credit
(aDL1 a is the size of the area that qualifies for
DL1a credit, etc,), and
aSFHA = the size of the community's SFHA
cDL = (DL1 x rDL1) + (DL2 x rDL2) + (DL3 x rDL3)
Documentation Provided by the Community
(1) The activity documentation requirements listed in Section 431.d must be met.
432.b. Freeboard (FRB)
The maximum credit for this element is 500 points.
The NFIP requires that the lowest floor of residential structures be elevated to or above the
base flood elevation and that non-residential structures be elevated or floodproofed to or
above the base flood elevation. Attached garages and utilities (including electrical, heating,
ductwork, ventilating, plumbing, and air conditioning equipment) must also be protected to
the base flood elevation (44 Code of Federal Regulations (CFR) §60.3(a)(3)). This can be
done by elevating them or using flood-resistant materials during construction.
A freeboard requirement adds height above the base flood elevation to provide an extra
margin of protection to account for waves, debris, miscalculations, or lack of data. A
freeboard requirement of one foot means that the level of protection for the lowest floor,
machinery and equipment, etc. is one foot above the base flood elevation.
32.
CRS Coordinator's Manual 430-10 Edition: 2013
Higher Regulatory Standards
Credit Criteria
(1) Lowest floor, utilities, and garages: For FRB credit, freeboard must be applied to the
elevation of the lowest floor of the building or to the elevation to which a non-
residential building is dry floodproofed, and to all components of the building, including
all utilities, ductwork, and attached garages. All portions of the building below the
freeboard level must be constructed using flood-damage-resistant materials. If the
garage floor is below the freeboard level, the garage must meet the opening and wet
floodproofing requirements for enclosures.
Two references on these requirements are Protecting Building Utilities from Flood
Damage, FEMA-348, and Flood Damage-Resistant Materials Requirements, Technical
Bulletin 2 (2008).
(2) The amount of freeboard is measured according to the following criteria:
(a) In A Zones, freeboard is measured from the top of the lowest floor. In V Zones, it is
measured from the bottom of the lowest horizontal structural member. If the
ordinance uses "lowest horizontal structural member" or similar language instead of
"lowest floor" in areas outside of the V Zone or coastal A Zones where CAZ credit
applies, 1 foot is added to the amount of freeboard credited. For example, if the
community's ordinance requires that buildings in the A Zones be elevated so the
bottom of the floor joists is at least 1.0 feet above the base flood elevation, the
ordinance is scored as requiring 2.0 feet of freeboard.
(b) For the purpose of calculating CRS credit, the 500-year flood elevation is considered
to be one foot higher than the base flood elevation, unless the community demon-
strates that it is higher. For example, if the community's ordinance requires that the
building be protected to at least the 500-year flood elevation, the ordinance is scored
as requiring 1.0 feet of freeboard.
(c) In AO Zones, base flood depths are provided instead of base flood elevations. Where
depths are not provided, the NFIP regulations require new buildings to be elevated
2 feet above the highest adjacent grade. Some communities misinterpret this
requirement as two feet of freeboard. Elevating 2 feet above the highest adjacent
grade in an AO Zone where no base flood depth is provided is a minimum
requirement of the NFIP and is not eligible for credit.
However, in AO Zones with depth numbers, the NFIP requires elevation above that
depth. Going higher than the specified depth warrants FRB credit, which is scored
the same as in an AE Zone.
(d) "Stem wall" construction involves constructing the foundation walls above grade,
filling the interior area, and pouring a slab over the fill. From the outside, the
building looks as though it is elevated on a crawlspace, but openings are not
required. Such buildings are categorized as Diagram 1.b in the FEMA Elevation
Certificate. This construction practice does not prohibit fill, but it limits the amount
of fill to the building footprint. If the regulations prohibit fill for new buildings, but
allow for stem wall construction, the credit is the average of the values in the "No
33
CRS Coordinator's Manual 430-11 Edition: 2013
Higher Regulatory Standards
filling restrictions" and "Compensatory storage required" columns in the table in the
Credit Points section, below.
(e) If the ordinance uses the encroached elevation using FEMA's standard allowable
maximum rise of one foot, add 0.5 feet to the amount of freeboard. Detailed riverine
flood studies that produce a floodway provide a flood elevation based upon the
floodway encroachment. In a Flood Insurance Study, these elevations are listed in
the "With Floodway" column in the Floodway Data Table. They are generally higher
than the "Without Floodway" or "Regulatory" flood elevations. For example, if the
community's ordinance requires that the building be protected to at least one foot
above this encroached elevation, the ordinance is scored as requiring 1.5 feet of
freeboard.
(f) Many communities have focused on elevating the top of the lowest floor, but have
allowed utilities (especially ductwork) to hang below the floor joists, where it can be
flooded. Flooded ductwork can add thousands of dollars to an insurance claim. This
is primarily a concern for buildings on crawlspaces. Buildings on slab foundations,
on pilings, and in V Zones typically have the utility facilities waterproofed or
elevated to a sufficient height.
To receive full credit for this element, electrical, heating, ventilation, plumbing, and
air conditioning equipment and other service facilities (including ductwork) must be
elevated or waterproofed to the base flood elevation plus freeboard. If the
community requires that electrical, heating, ventilation, plumbing, and air
conditioning equipment and other service facilities (including ductwork) be elevated
or made of flood-resistant materials above the base flood elevation, but does not
require these facilities to be elevated or protected to the freeboard level, then the
value for freeboard in the table is considered to be 75% of the elevation requirement.
If the utilities and ductwork are not required to be elevated, floodproofed, or
otherwise protected to the base flood elevation, there is no credit for FRB.
Credit Points
FRB = as shown below, based on the required freeboard
Freeboard No filling Compensatory Fill prohibited
restrictions storage required
1 foot 100 110 120
2 feet 225 250 280
3 feet 375 440 500
(1) More points are provided if the community prohibits buildings on fill (e.g., they must be
constructed on piers, pilings, or flow-through crawlspaces) or requires compensatory
storage if filling is used.
34.
CRS Coordinator's Manual 430-12 Edition: 2013
Higher Regulatory Standards
(2) The values for freeboard levels not shown are extrapolated from the credit points table.
For example, the value for 1.5 feet of freeboard where compensatory storage is required
is the average of the values for 1.0 foot and 2.0 feet: (110 + 250) = 2 = 180 points.
(3) If a community has more than three feet of freeboard, the regulations will be reviewed
for special credit higher than the points shown in the credit points table, above. The
community will need to provide additional information to warrant the higher credit, such
as a demonstrated expectation of new growth in the area.
(4) Other adjustments to the scoring are explained in the section on credit criteria, above.
Impact Adjustment
FRB credit is adjusted based on the ratio of the area affected by the freeboard requirement
to the area of the SFHA. See Section 431.c on calculating an impact adjustment. The
following additional criteria apply.
(1) Areas requested for FRB credit must exclude areas credited for OSP or DL2.
(2) There are instances in which a community may have different freeboard requirements in
different areas, such as
• The community does not require freeboard where there are no base flood elevations,
such as in approximate A Zones and AO Zones;
• Freeboard is only required for elevated buildings (non-residential buildings may be
floodproofed to the base flood elevation without freeboard);
• Manufactured homes have a different elevation requirement; or
• There is higher freeboard in a V Zone or a floodplain subject to deeper flooding.
In these cases, the formulae should use FRB#1, FRB#2, etc. to calculate the appropriate
values for the different areas.
rFRB = aFRB , where
aSFHA
aFRB = the size of the area(s) that qualifies for FRB credit, and
aSFHA = the size of the community's SFHA
Example 432,b-1.
South Scottsdale is a fictitious community used for CRS examples
(see Figure 430-1). The City requires that all new buildings and
substantial improvements be elevated two feet above the base flood
elevation, To minimize floodplain encroachments, the City also
requires that all new buildings be constructed either (1) without fill on
CRS Coordinator's Manual 430-13 Edition: 2013
Higher Regulatory Standards
flow-through foundations, such as piers or crawlspaces with sufficient
openings, or (2) on slab foundations with compensatory storage
required for any filling.
FRB = 250
These regulations apply throughout the SFHA. In the approximate
A Zones of Tributaries A and B, buildings must be elevated two feet
above the base flood elevation calculated by the permit applicant
(which is credited in Activity 410 (Floodplain Mapping)).
These regulations only have an impact where new buildings and
substantial improvements can be constructed. As noted in Section
431.c(4), areas set aside from development as preserved open space
are excluded from the impact adjustment calculations.
aFRB = the size of the area(s) that qualify for FRB credit, i.e., the
SFHA not credited for OSP under Activity 420 (Open
Space
Preservation)
aSFHA = 504.4
aOSP = 242.9
aFRB = aSFHA— aOSP = 504.4 —242.9 = 261.5
rFRB = aFRB = 261.5 = 0.52
aSFHA 504.4
According to Section 433, Credit Calculation, the value for two feet of
freeboard with compensatory storage (250) is multiplied by the ratio for
rFRB, 0.52. The total credit for South Scottsdale's freeboard
requirement, cFRB, is 52% of 250.
Documentation Provided by the Community
(1) The activity documentation requirements in Section 431.d must be met.
CRS Coordinator's Manual 430-14 Edition: 2013
Higher Regulatory Standards
'1310 , r ��
` t310
•. 1 a _______,_:_ fi
1309 , +
. ,
tvier7;308 i� McCormick
7 9 Creek
Jr
• 1
7jQe r 1
„ : ... .: . . ,.. ..,j : i: South Scottsdale
z :::t:::f' Li. `� , III
t \ : :\ • AE Zone—Flood Fringe
.... � ,
_ � '�.;. 'Approximate A Zone �
l �a �1: � � ,, h-
Z.. P
,�°` �. �'L°' ,X
89 • t
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at pi
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v 1277
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Indian ...:.,:::: : ,N,41'5 VW° MI
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-I- t \ ' !L : .. .....
1 ,
4i1 : ! .Tributary B L `� -� _
. : rw ..�':s l5.11,t E.
Higher Regulatory Standards
Freeboard (FRB): All AE and A Zones, except preserved open spaces
Protection of critical facilities (PCF): All floodway areas except preserved open spaces
Figure 430-1. South Scottsdale's impact adjustment map for Activity 430.
37
CPS Coordinator's Manual 430-15 Edition: 2013
-
- _
•
. u
A :1F 1----
• Y V•
''' ; i INI I! ,rte. ' -
tot
•
H •
National Flood Insurance Program (NFIP)
Floodplain M
Requirements
A Study Guide and Desk Reference for Local Officials
FEMA 480
February 2005
e
�' FEMA
,,,,D,„,.;:
.____,
In Minnesota, one watershed district took another regulatory approach, en-
acting regulations that restricted encroachments in the flood fringe to 20 percent
of the total floodplain area. In Washington State, some communities treat higher
velocity and deeper flood fringe areas as floodways and make development in
those areas comply with the floodway construction standards.
The Community Rating System credits more restrictive
floodway mapping standards under Activity 410 Additional
Flood Data, Section 411.c in the CRS Coordinator's Manual
NFIPI S and the CRS Application.
COMPENSATORY STORAGE
The NHP floodway standard in 44 CFR 60.3(d) restricts new development
from obstructing the flow of water and increasing flood heights. However, this
provision does not address the need to maintain flood storage. Especially in flat
areas, the floodplain provides a valuable function by storing floodwaters. When
fill or buildings are placed in the flood fringe, the flood storage areas are lost and
flood heights will go up because there is less room for the floodwaters. This is
particularly important in smaller watersheds which respond sooner to changes in
the topography.
For this reason, some communities adopt more restrictive standards that
regulate the amount of fill or buildings that can displace floodwater in the flood
fringe. One simple approach is to prohibit filling and buildings on fill—all new
buildings must be elevated on columns or flow-through crawlspaces.
Check your statutory authority, because in some states buildings are allowed
only if they are on fill. Some communities prefer buildings on fill because it
provides a safe spot above flood levels outside the building walls.
Another approach is to require compensatory storage to offset any loss of
flood storage capacity. The developer is required to offset new fill put in the
floodplain by excavating an additional floodable area to replace the lost flood
storage area. This should be done at "hydraulically equivalent" sites—fill put in
below the 10-year flood elevation should be compensated by removal of soil
below that elevation elsewhere in the floodplain.
• • The Community Rating System credits prohibition of
fill and compensatory storage under Activity 430, Section i4 32
1 in the CRS Coordinator's Manual and the CRS Ap-
NFIP/CRS pleation. See CRS Credit for Higher Regulatory Standards
for example regulatory language.
Additional Regulatory Measures 6-21
39
r a I t ' -:..fr'
•
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, ______
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"iv ,..,/ ..,/ ,,,- z , , 4
_-., , .,, _ fir,;* * - • 0' . ,- - ':',,A . ,4
-A. ....._ .,,-. --' ' -,,, '— ; ':.-- -- - ,./..., ., _ „...... .,, -rot
Estimated high`. Tr . _ _ - ; , . -, levated utilities
National Flood Insurance Program
Community Rating System
CRS Credit for
Higher Regulatory Standards
2006
QOYr�F
:, :'
x � y FFMA
-Up ss-
Common Problems
Some communities have submitted regulatory language that prohibits hazardous materials
storage or one other type of critical facility. These have not received full PCF credit
because they do not include the majority of critical facilities.
f. Protection of Floodplain Storage Capacity (PSC)
Although a building constructed on fill and elevated above the base flood elevation meets
the NFIP regulations, filling a substantial portion of the floodplain reduces storage for
flood water and tends to increase peak flows downstream. Prohibiting fill, or requiring
that if fill is placed in the floodplain, an equal volume of storage be made available, will
reduce this problem.
NFIP Requirement
The basic NFIP requirement in
Compensatory storage
Fill L_J 9 excavated riverine situations is that new
K -. : ,ti ter: development must not restrict
conveyance of floodwaters. A
CROSS-SECTION VIEW floodway is adopted to identify the
area needed to convey the base flood
House built $,cva onCnntoor and that area is kept free of
on Fill ,Line,`/'''`'+,`'A,,,, obstructions (Sections 60.3(c)(10) and
:-":i'i,,,,,,,,,;::*': (d)(2) and (3)).
"' The balance of the floodplain, the
fringe, may be filled or otherwise
developed. Although the NFIP
requirement has an important impact
on future flood heights, it does not
Compensatory
Storage Excavation account for the loss of floodplain
- storage caused by allowing the fringe
to be filled.
Illustration from the explanation of the King County,
Washington, compensatory storage requirement. If Storage is especially important in flat
fill is placed in the floodplain, an equal amount must areas with wide floodplain fringes.
be removed from the same elevation to provide "a
hydraulically equivalent volume of excavation." Much of the slow-moving flood water
is held in the fringe during a flood.
Filling or constructing a levee that
removes the storage capacity of the fringe means more water will be sent downstream,
resulting in increased flood heights. On the other hand, in many places, building on fill is
the safest form of floodplain construction, so communities should not summarily enact a
prohibition just for CRS credit.
41
Credit for Higher Regulatory Standards --31— Edition: 2006
THE CODE OF GRIFFIN, GEORGIA
ARTICLE III. PROVISIONS FOR FLOOD DAMAGE REDUCTION
Sec. 50-91. General standards for construction.
Sec. 50-92. Building standards.
Sec.50-93.Appeal procedures.
Sec. 50-94.Violations,enforcement and penalties.
Sec. 50-92. Building standards.
(a) Building standards for structures and buildings within the future-conditions floodplain. The following
provisions, in addition to those in section 50-91, shall apply:
(1) New construction. New construction of principal buildings, including manufactured homes shall
not be allowed within the limits of the future-conditions floodplain unless all requirements of this
chapter have been met. If all of the requirements of this chapter have been met, all new
construction shall have the lowest floor, including basement, elevated no lower than three feet
above the base flood elevation or one foot above the future-conditions flood elevation,
whichever is higher. Should solid foundation perimeter walls be used to elevate the structure,
openings sufficient to equalize the hydrologic flood forces on exterior walls and to facilitate the
unimpeded movements of floodwaters shall be provided in accordance with standards of
section 50-91(e).
(2) Substantial improvements. Substantial improvement to any principal structure or manufactured
home shall have the lowest floor, including basement, elevated no lower than three feet above
the base flood elevation or one foot above the future-conditions flood elevation, whichever is
higher. Should solid foundation perimeter walls be used to elevate a structure, openings
sufficient to equalize the hydrologic flood forces on exterior walls and to facilitate the unimpeded
movements of flood waters shall be provided in accordance with standards of section 50-91(e).
A no fill ordinance was not located.
A compensatory storage requirement was not located.
Ill
AMERICAN INSTITUTES I Cale RESEARCII '
Evaluation of the
National Flood Insurance Program's
Building Standards
Christopher P. Jones, William L. Coulbourne,
Jamie Marshall, and Spencer M. Rogers, Jr.
Christopher Jones and Associates
- _ = October 2006
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Prepared under subcontract to the American Institutes for Research
.- as part of the 2001 -2006 Evaluation of the National Flood Insurance Program
vii
EXECUTIVE SUMMARY
Background and Purpose of this Study
Floodplain management regulations adopted by communities and states contain
provisions that affect new construction in floodplain areas. These regulations must equal or
exceed National Flood Insurance Program(NFIP) minimum design and construction
requirements for buildings in the Special Flood Hazard Area (SFHA), and are intended to
minimize flood damage to buildings during the base flood (also known as the 100-year flood,
and as the 1-percent annual chance flood).
The purpose of this study was to evaluate those design and construction requirements,
with particular emphasis on: 1) damages prevented or induced by strict adherence to those
minimum requirements, and 2) the costs and benefits of modifying the minimum requirements to
reduce building damages during flooding.
Specifically, this study was designed and conducted to address three sets of questions
regarding NFIP building standards for typical single family homes in the SFHA:
• What impacts have the NFIP's building standards for new construction in Special
Flood Hazard Areas had on risk exposure and property loss? Which standards are
the most and least effective in reducing exposure and property losses due to
floods? Is the cost of implementing the major standards commensurate with their
benefits?
• Are the NFIP's standards for construction and building design adequate and
sufficiently stringent so that losses are minimized at a reasonable cost to
communities and property owners when flood damage occurs? Are the standards
and incentives sufficient to protect against flood risks that may be increasing in
the future?
• Do the NFIP's building standards effectively protect buildings from damages
during the 100-year flood? If current standards are not effective, how should
FEMA change them? Are higher levels of protection achievable and more
important, are the benefits achieved by these standards commensurate with the
costs associated with meeting them?
These issues were addressed through a study that included the following:
• Review of building flood damage and foundation performance in coastal and non-
coastal floodplains.
• Review of the literature and calculation of construction costs for one-and two-
story houses with several foundation types under a variety of flood conditions.
• Calculation of the costs of adding freeboard and changing foundations. FEMA's
benefit-cost analysis (BCA) model was modified in this study to allow
The Evaluation of the National Flood Insurance Program 44
Evaluation of the National Flood Insurance Program's Building Standards
viii
generalized benefit/cost calculations to be made with all cost inputs expressed as a
percentage of the initial (at-BFE)building cost. The model was run with variable
discount rates (ranging from 3% to 9%), flood damage functions (V and Coastal
A, and A), BFEs (in coastal areas, ranging from 12 ft to 20 ft mean sea level
[msl]) and Flood Hazard Factors (FHF) in riverine areas, ranging from 25 to 150.
• The B/C models run in this study account for building and contents damages, and
do not account for other economic costs to the building owner or community (e.g.,
clean-up and demolition costs, uninsured losses, displacement and relocation
costs, loss of jobs and tax base, etc.). The resulting benefit-cost ratios (B/C) are
conservative, and will understate the true benefits associated with exceeding
minimum NFIP building standards.
• Calculation of the maximum justified cost of mitigation, i.e., freeboard and/or
foundation changes at the time of initial construction -- expressed as a percentage
of initial construction cost -- that would yield a B/C greater than or equal to 1.0.
All cost inputs were expressed as a percentage of the initial (at-BFE) construction
cost to generalize the results.
• Examination of the sensitivity of the B/C results to inclusion of displacement
costs when building occupants must move out of flood damaged homes.
• Examination of flood insurance premium discounts for adding freeboard, and
development of a general method to determine the time to recover the costs of
freeboard through future flood insurance premium savings.
General Findings
On an individual building level, NFIP building standards have reduced flood damage
relative to nearby pre-FIRM type structures. Flood losses for new construction are reduced
through elevation and proper selection of the building foundation. Post-storm observations and
calculations made during this study demonstrate that incorporation of freeboard is one of the
most effective means of reducing property losses.
Generally speaking, NFIP building standards do reduce flood losses to new construction
under present day base flood events. However,building standards are implemented in
conjunction with the Flood Insurance Rate Map (FIRM), which does not account for increasing
flood hazards in the future. Thus, while NFIP building standards may be generally effective
today, their future effectiveness will be reduced as the FIRM becomes obsolete due to changing
flood conditions. Revising building standards may be one way to compensate for changing flood
conditions in the future.
This study found, for the residential buildings analyzed, the cost of adding freeboard or
installing a more flood-resistant foundation at the time of construction is modest but the benefit
of doing so can be great, particularly in coastal areas subject to wave effects and riverine
floodplains with small flood hazard factors. Incorporating freeboard and/or changing the
The Evaluation of the National Flood Insurance Program
Evaluation of the National Flood Insurance Program's Building Standards
ix
foundation type would also help to reduce future flood damage resulting from sea level rise and
erosion in coastal areas, and from development impacts in riverine areas.
Under the current flood premium rate structure, flood premium discounts will be
sufficient to recover the incremental costs borne by property owners to incorporate freeboard at
the time of initial construction -- in just a few years time for many buildings.
However, floods more severe than the 100-year flood do occur, and incorporation of
freeboard and modified foundations can help reduce losses from such floods. This study
indicates that higher levels of protection are achievable for single family structures, and that the
benefits of doing so will exceed the costs, particularly in high hazard areas. Additional B/C
analyses could help to define a flood return period for which additional elevation is justified for
other classes of structures.
With a few exceptions, NFIP building standards evaluated by this study generally protect
against the 100-year flood. NFIP flood insurance premium rates generally promote sound
construction practices and reduce potential flood damages. However, some changes to building
standards and insurance premium rates are warranted, as a way of further reducing flood
damages,providing additional incentives for flood loss reduction, and eliminating disincentives.
While this study did not investigate building practice effects on flood loss reduction at a
community level, extension of the individual building findings to a broader scale seems
reasonable. Reduced flood damage to individual buildings aggregates to reduced flood losses and
disruption to the community. Study authors have observed this first-hand as part of post flood
investigations -- where flood damage was widespread and great, individuals and communities
often struggle to recover, while other nearby communities with less flood damage recover
quickly.
This study did not investigate the effects of potential changes in NFIP building standards
on the flood insurance fund, disaster assistance payments and other financial aspects of the NFIP
and FEMA. However, since modified building standards could reduce flood damage at the
individual building level, it seems reasonable to expect flood claims, disaster assistance and
other post-disaster payments might also be reduced. The exact impact on the NFIP would depend
on flood premiums received and payments made. The study authors believe that the cost of
implementing building standards changes would be small, since the NFIP and the participating
communities already enforce standards which are similar to the changed standards this study
recommends.
Detailed Findings
At the time of initial construction, the incremental costs of replacing minimally compliant
A zone foundations (such as slab-on-fill and crawlspace foundations)with pier foundations or
pile foundations are relatively small, generally less than 5% to 10% of the cost of the building.
In Coastal A zones, post-storm field studies have shown that minimally compliant A zone
foundations often fail, and this replacement is warranted. In A zones outside coastal areas, NFIP
compliant slab-on-fill and crawlspace foundations are generally adequate, and the incremental
cost of changing to a pile foundation is not likely justified (but owners may wish to do so to
The Evaluation of the National Flood Insurance Program } ! /_
Evaluation of the National Flood Insurance Program's Building Standards �( y�i+
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create under-house parking). However, changing to a pier foundation is probably justified,
especially for flood depths more than a few feet above grade.
At the time of initial construction, the cost of incorporating freeboard in a pile or masonry
pier foundation averages approximately 1% to 2% of the at-BFE building cost for 4 ft of added
freeboard (approximately 0.25% to 0.5% per foot of freeboard).
At the time of initial construction, the cost of incorporating freeboard in a masonry wall
with interior pier (crawlspace)foundation averages approximately 3% to 6% of the at-BFE
building cost for 4 ft of added freeboard (approximately 0.8% to 1.5%per foot of freeboard).
At the time of initial construction, the cost of incorporating freeboard in a fill foundation
averages approximately 3% to 11% of the at-BFE building cost for 4 ft of added freeboard.
Although the fill quantity and fill cost do not increase linearly with freeboard, they add an
average of 0.8% to 3.0 % per foot of freeboard to the at-BFE building cost.
As expected, the B/C ratios calculated in this study decrease with increasing discount
rate,with all other factors held constant. B/C ratios also decrease with increasing BFE and FHF,
indicating that a foot of freeboard is worth less (in terms of damage reduction) in areas where
there is a greater vertical spread in flood elevations associated with different return periods.
B/C calculations were tabulated and the B/Cs were determined for various combinations
of freeboard, additional construction cost and discount rate. The data were then examined to
identify the percent of additional construction cost that an owner would be justified in spending
at the time of construction (B/C = 1.0) for each freeboard-BFE-discount rate or freeboard-FHF-
discount rate combination.
In the V zone and Coastal A zone cases studied, calculations show that it is worth
spending from 103% to 106% of the at-BFE building cost to add one to four feet of freeboard,
and in some cases it may be worth spending up to 107% to 114% of the at-BFE building cost.
In the A zone cases studied, calculations show that it is worth spending less than in V
zones and Coastal A zones to add freeboard—this is due to the fact that A zone flood depth-
damage functions predict less damage for a given flood depth than do the V zone/Coastal A zone
functions. The A zone calculations show it is worth spending from 100.5% to 102% of the at-
BNE building cost to add one to four feet of freeboard, and in some cases it may be worth
spending up to 103% to 106% of the at-BFE building cost.
A sensitivity analysis was undertaken to investigate the effect of including displacement
costs in the B/C calculations. Using BCA default displacement times, the effect varies slightly
between flood hazard zones and with number of stories in an A zone. However, the effect can be
generalized as follows: adding monthly displacement costs equal to 1% of the initial (at-BFE)
building cost increases the computed B/C by approximately 10%, and so forth.
The relationship between initial freeboard costs and flood premium discounts was also
considered in a separate analysis. Even if future building and contents damages prevented are not
considered the annual flood premium savings are generally sufficient to pay for the costs of
adding freeboard in several years time for many buildings. In the case of V zone buildings, the
The Evaluation of the National Flood Insurance Program
Evaluation of the National Flood Insurance Program's Building Standards
xi
time required to recover freeboard costs through flood premium savings is short—a year or two.
In the case of A zone buildings, the recovery time can extend to more than 15 years, due to the
lower A zone premiums and premium discounts,which are used to offset the initial freeboard
cost.
Recommendations
B-1. The NFIP should not allow new A zone construction to be built with the top of the
lowest floor at the BFE. Instead, the NFIP should require the top of the lowest floor of
A zone structures to be built above the BEE such that the floor system is not in contact
with flood waters during the base flood. This could be accomplished by either: 1)
requiring sufficient freeboard, or 2) by changing the lowest floor reference elevation in
A zones to be consistent with V zones (i.e., the bottom of the lowest horizontal
structural member supporting the lowest floor must be at or above the BFE).
B-2. The NFIP should require at least 1 foot of freeboard for all new construction in the
special flood hazard area. The exact freeboard amount should be guided by several
factors:
• Freeboard requirements contained in consensus standards such as the American
Society of Civil Engineer's (ASCE) standard ASCE 24.ASCE 24 contains freeboard
provisions which vary by building importance (the standard requires critical
facilities to be elevated higher above the BFE than typical residential structures, for
example). The ASCE 24 freeboard provisions apply to the lowest floor, the use of
flood resistant materials and utilities.
• Future flood conditions.ASCE 24 does not account explicitly for future increases in
flood hazards, thus, freeboard in excess of ASCE 24 requirements may be
appropriate in some flood hazard areas. The NFIP should consider flood loss
reduction under present day base flood conditions and under future flood conditions
when it establishes freeboard requirements.
• Flood elevation frequency. The NFIP should attempt to establish freeboard
requirements that are flood-risk consistent. For example, 1 foot of freeboard at a site
with a flood hazard factor of 20 may yield protection against a certain flood return
period event. Equivalent protection at a different site with a flood hazard factor of
75 would require more than 1 foot of freeboard.
B-3. The NFIP should mandate V zone design and construction practices in Coastal A zones
(e.g., requiring open foundations and the area below the BFE to be free of obstructions,
making the lowest floor reference elevation the bottom of the lowest horizontal
structural member supporting the lowest floor, designing for simultaneous action of
flood and wind). Some communities have mandated V zone standards in A zones for
years, but implementation of this recommendation on a larger scale would require
changes to the flood hazard mapping process and the FIRM. Note that the 2005 edition
of ASCE 24 requires new construction in Coastal A zones to meet V zone standards,
The Evaluation of the National Flood Insurance Program 4j
Evaluation of the National Flood Insurance Program's Building Standards
xii
and the FEMA has published supporting post-Katrina Coastal A zone construction
guidance.
B-4. The B/C results of this study are sensitive to the flood depth-damage function used in
the analysis. The NFIP should, on an ongoing basis, review and update depth-damage
functions based on flood claims data, results of Mitigation Assessment Team (MAT)
investigations and other data. This may require collection of some additional data now
deemed optional during the flood claims adjustment process.
B-5. Flood insurance premium rates should reflect anticipated flood damages and provide
incentives to property owners and communities to exceed minimum NFIP building
standards. The Community Rating System (CRS) does this on a community scale, but
additional effort is needed to provide incentives to individuals. For example:
• The NFIP should re-evaluate flood insurance premium discounts for buildings in
A zones. Current A zone discounts effectively cease at one to two feet above the
BFE (unlike V zones where substantial discounts are awarded for up to four feet
of freeboard). Additional discounts for increased freeboard in A zones may be one
of the most powerful arguments for better construction that can be made to
property owners.
• The NFIP should revise flood premium rates and coverage for NFIP-compliant
pile-elevated buildings outside the V zone. Present rates and coverage penalize
property owners who might otherwise adopt the superior pole-type construction,
with pilings extending above the lowest floor to a higher floor or the roof.
B-6. The NFIP should consider development of an A Zone Risk Factor Rating Form and
process, similar to that in place for V zones. This action could provide another way to
reward A zone building owners to adopt design and construction practices that exceed
NFIP minimum standards.
The Evaluation of the National Flood Insurance Program
Evaluation of the National Flood Insurance Program's Building Standards
Using Freeboard to Elevate Structures above Predicted Floodwaters Page 1 of
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Home CZM Home Program Areas StorrnSmart Coasts-Managing Erosion and Flooding StormSmart Communities Using Freeboard to Elevate Structures
StormSmart Communities - Using Freeboard to Elevate Structures above Predicted
Floodwaters
Freeboard is elevating a building's lowest floor above predicted flood elevations by a small additional height(generally 1-3 MASSACHUSETTS OFFICE OF
feet above National Flood Insurance Program[NFIP]minimum height requirements).See CZM's printer friendly Freeboard COASTAL ZONE MANAGEMENT •
Fact Sheet .
Without Freeboard ', With 3' of Freeboard CZM HOME
StormSmart Communities-Tools
for Local Officials
r,, 11 ro
StormSmart Communities-Home
Publications
t "
\ Pilot Projects
(Annual flood insurance:$5,499 (Annual Annual load insurance:S2,08i)
\ Funding Sources
Elevating a home a few feet above legally mandated heights has very little effect on the overall look of a home,yet it can Freeboard-Elevating above Flood
lead to substantial reductions in flood insurance,substantially decrease the chances a home will be damaged by storms Level
and flooding,and help protect against sea level rise.
Interpreting FEMA Flood Maps
What Are the Benefits of Freeboard?
Hazard Identification and Mapping
• Increased protection from floods and storms.Storm waters can and do rise higher than shown on Flood Insurance
Rate Maps(FIRMS).Freeboard helps protect buildings from storms larger than those that FIRMs are based on,and Mitigation and Shore Protection
provides an added margin of safety to address the flood modeling and mapping uncertainties associated with FIRMS.
About StormSmart Communities
• Better preparation for ongoing sea level rise.Massachusetts has experienced a relative sea level rise of
approximately i foot over the past 100 years.Since elevations on FIRMs do not include sea level rise,freeboard will No Adverse Impact(NAI)Approach
help keep structures above floodwaters as storm surge elevations increase.
• Greatly reduced flood insurance premiums.Recognizing that freeboard reduces flood risk,the Federal Emergency Related Items
Management Agency(FEMA,which administers the NFIP)provides substantial(sometimes more than 50 percent)
reductions in flood insurance premiums for structures incorporating freeboard.These savings can rapidly accumulate, StormSmart Coasts Home
especially over the life of a normal mortgage. Coastal Landscaping
Example of Savings on NFIP Premiums* with Freeboard Erosion and Shoreline Change
V Zone? A Zone?
Annual savings 30-year savings Annual savings 30-year savings CZM Site Map
1'freeboard $1,360(25%) $40,800 $502(41%) $15,060
2'freeboard $2,73D(50%) $81,900 $678(55%) $20,340 CONTACT CZM
3'freeboard $3,415(62%) $102,450 $743(60%) $22,290
*NFIP premiums based on May 2007 rates for a one-floor residential structure with no basement built after a FIRM was issued for the community(post-
FIRM rates differ from pre-FIRM rates).$500 deductible/$250,000 coverage for the building/$100,000 for contents.
The expense of incorporating freeboard into new structures is surprisingly low,generally adding only about 0.25 to 1,5
percent to the total construction costs for each foot of added height,according to a 2006 FEMA-commissioned study
(Evaluation of the National Flood Insurance Program's Building Standards).The minor resulting increase in monthly
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Jsing Freeboard to Elevate Structures above Predicted Floodwaters Page 3 of
mortgage payments is generally more than offset by savings on NFIP premiums.Consequently,adding freeboard typically
saves homeowners money.
Consider,for example,a proposed one-story building in the V zone;that will cost$250,000 to build at minimum legal
standards(the NFIP requires that all homes in the floodplain be elevated to at least the base flood elevation[BFE],mapped
on FIRMs).According to the study cited above,adding each foot of freeboard to a home on piles or piers adds about 0.4
percent to total construction costs(about$1,000 a foot in this example).If the owner takes out a mortgage at 6.5 percent
APR for the total construction costs,he or she will have lower monthly payments(mortgage plus NFIP premiums)with 3
feet of freeboard,even though the construction costs are higher.
Home at minimum legal height Home with 3'of freeboard
Monthly mortgage payments $1,580.17 Monthly mortgage payments $1,599.13(+$18.96)
Monthly flood insurance $458.25 Monthly flood insurance $173.67(-$284.58)
Total monthly cost $2,038.42 Total monthly cost $1,772.80(-$265.62)
In this example,adding 3 feet of freeboard saves the homeowner$265.62 per month,or$95,623.67 over a 30-year
mortgage.Benefits in A zones2 are generally less dramatic,but still substantial.To determine NFIP premiums for a specific
property,see a licensed insurance agent.
Who Can Benefit from Freeboard?
Nearly everyone building in floodplains can better protect themselves and their property and save on flood insurance by
including freeboard into their construction and reconstruction projects.Additional benefits include:
• Homeowners-Whether or not you live in the house year-round,having it elevated increases the chances that it will
weather storms safely,decreasing your worry and protecting your investment.If you're building a new home,or doing a
renovation,ask your builder/designer about incorporating freeboard.
• Builders/contractors-Freeboard provides a competitive edge over other builders,allowing you to market the benefits
of reduced flood insurance and flood risk to potential buyers.When doing retrofits(especially those requiring bringing
structures up to current NFIP standards),explain the benefits of freeboard to your clients.
• Municipalities-When constructing new municipal buildings(schools,fire stations,etc.)use freeboard as a means of
saving tax dollars.Encourage all new construction in your community to include freeboard. (NOTE:the Massachusetts
Attorney General's office has recently rejected bylaws requiring freeboard,but municipalities may promote its use.)
• Businesses-Freeboard helps:protect your buildings,important records,and inventory from flooding;drastically
decrease your recovery/clean-up time after storm;and potentially save your business.The Institute for Business and
Home Safety reports that more than 25 percent of businesses that close due to storm damage never reopen.
For More Information
• For technical information on the costs of incorporating different flood-resistant building techniques(including freeboard),
see the American Institutes for Research's 2006 study,Evaluation of the National Flood Insurance Program's Building
Standards.
• For general information on the National Flood Insurance Program,see www.FloodSmart.00v.
• For specific questions on flood insurance rates,see a licensed insurance agent.
• Communities looking for more information on the National Flood Insurance Program can contact Richard Zingarelli,
Massachusetts NFIP Coordinator: (617)626-1406,Richard.ZinciarelliC1state.ma.us.
• Businesses looking to prepare for storms and other catastrophic events should visit the Institute for Business and Home
Safety's website.
1V-aowos:This Flood Insurance Rate Map (FIRM)designation refers to coastal areas that are subject to the highest levels
of wave energy and flooding.
2A zones:Also a FIRM designation,coastal A zones are subject to flooding but with less wave energy than V zones(i.e.,
wave heights less than 3 feet).
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