santa rosa county, florida - northwest florida water...
TRANSCRIPT
VOLUME 1 OF 1
SANTA ROSA COUNTY, FLORIDA AND INCORPORATED AREAS COMMUNITY NAME COMMUNITY NUMBER GULF BREEZE, CITY OF 120275 JAY, TOWN OF 120339 MILTON, CITY OF 120276 SANTA ROSA COUNTY, UNINCORPORATED AREAS 120274
Revised Preliminary: July 29, 2019
REVISED: TBD
FLOOD INSURANCE STUDY NUMBER 12113CV000B Version Number 1.3.1.2
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TABLE OF CONTENTS Volume 1
Page
SECTION 1.0 – INTRODUCTION 1 1.1 The National Flood Insurance Program 1 1.2 Purpose of this Flood Insurance Study Report 2 1.3 Jurisdictions Included in the Flood Insurance Study Project 2 1.4 Considerations for using this Flood Insurance Study Report 5
SECTION 2.0 – FLOODPLAIN MANAGEMENT APPLICATIONS 15 2.1 Floodplain Boundaries 15 2.2 Floodways 21 2.3 Base Flood Elevations 22 2.4 Non-Encroachment Zones 22 2.5 Coastal Flood Hazard Areas 23
2.5.1 Water Elevations and the Effects of Waves 23 2.5.2 Floodplain Boundaries and BFEs for Coastal Areas 24 2.5.3 Coastal High Hazard Areas 25 2.5.4 Limit of Moderate Wave Action 26
SECTION 3.0 – INSURANCE APPLICATIONS 27 3.1 National Flood Insurance Program Insurance Zones 27 3.2 Coastal Barrier Resources System 27
SECTION 4.0 – AREA STUDIED 29 4.1 Basin Description 29 4.2 Principal Flood Problems 29 4.3 Non-Levee Flood Protection Measures 30 4.4 Levees 31
SECTION 5.0 – ENGINEERING METHODS 31 5.1 Hydrologic Analyses 32 5.2 Hydraulic Analyses 49 5.3 Coastal Analyses 55
5.3.1 Total Stillwater Elevations 56 5.3.2 Waves 58 5.3.3 Coastal Erosion 58 5.3.4 Wave Hazard Analyses 58
5.4 Alluvial Fan Analyses 77
SECTION 6.0 – MAPPING METHODS 77 6.1 Vertical and Horizontal Control 77 6.2 Base Map 78 6.3 Floodplain and Floodway Delineation 79 6.4 Coastal Flood Hazard Mapping 114 6.5 FIRM Revisions 119
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6.5.1 Letters of Map Amendment 119 6.5.2 Letters of Map Revision Based on Fill 119 6.5.3 Letters of Map Revision 120 6.5.4 Physical Map Revisions 120 6.5.5 Contracted Restudies 120 6.5.6 Community Map History 121
SECTION 7.0 – CONTRACTED STUDIES AND COMMUNITY COORDINATION 122 7.1 Contracted Studies 122 7.2 Community Meetings 124
SECTION 8.0 – ADDITIONAL INFORMATION 126
SECTION 9.0 – BIBLIOGRAPHY AND REFERENCES 127
Figures Page
Figure 1: FIRM Panel Index 7 Figure 2: FIRM Notes to Users 8 Figure 3: Map Legend for FIRM 11 Figure 4: Floodway Schematic 21 Figure 5: Wave Runup Transect Schematic 24 Figure 6: Coastal Transect Schematic 26 Figure 7: Frequency Discharge-Drainage Area Curves 38 Figure 8: 1% Annual Chance Total Stillwater Elevations for Coastal Areas 57 Figure 9: Transect Location Map 76
Tables Page
Table 1: Listing of NFIP Jurisdictions 2 Table 2: Flooding Sources Included in this FIS Report 16 Table 3: Flood Zone Designations by Community 27 Table 4: Coastal Barrier Resources System Information 28 Table 5: Basin Characteristics 29 Table 6: Principal Flood Problems 30 Table 7: Historic Flooding Elevations 30 Table 8: Non-Levee Flood Protection Measures 31 Table 9: Levees 31 Table 10: Summary of Discharges 33 Table 11: Summary of Non-Coastal Stillwater Elevations 38 Table 12: Stream Gage Information used to Determine Discharges 49 Table 13: Summary of Hydrologic and Hydraulic Analyses 50 Table 14: Roughness Coefficients 55 Table 15: Summary of Coastal Analyses 56
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Table 16: Tide Gage Analysis Specifics 57 Table 17: Coastal Transect Parameters 60 Table 18: Summary of Alluvial Fan Analyses 77 Table 19: Results of Alluvial Fan Analyses 77 Table 20: Countywide Vertical Datum Conversion 78 Table 21: Stream-Based Vertical Datum Conversion 78 Table 22: Base Map Sources 78 Table 23: Summary of Topographic Elevation Data used in Mapping 79 Table 24: Floodway Data 81 Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams 89 Table 26: Summary of Coastal Transect Mapping Considerations 115 Table 27: Incorporated Letters of Map Change 120 Table 28: Community Map History 122 Table 29: Summary of Contracted Studies Included in this FIS Report 122 Table 30: Community Meetings 125 Table 31: Map Repositories 126 Table 32: Additional Information 127 Table 33: Bibliography and References 128
Volume 1 Exhibits
Flood Profiles Panel Blackwater River 01-07 PEast Bay River 08 PEscambia River 09-13 PPace Mill Creek 14-15 PPond Creek 16-18 PYellow River 19-20 P
Published Separately
Flood Insurance Rate Map (FIRM)
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FLOOD INSURANCE STUDY REPORT SANTA ROSA COUNTY, FLORIDA
SECTION 1.0 – INTRODUCTION
1.1 The National Flood Insurance Program The National Flood Insurance Program (NFIP) is a voluntary Federal program that enables property owners in participating communities to purchase insurance protection against losses from flooding. This insurance is designed to provide an alternative to disaster assistance to meet the escalating costs of repairing damage to buildings and their contents caused by floods. For decades, the national response to flood disasters was generally limited to constructing flood-control works such as dams, levees, sea-walls, and the like, and providing disaster relief to flood victims. This approach did not reduce losses nor did it discourage unwise development. In some instances, it may have actually encouraged additional development. To compound the problem, the public generally could not buy flood coverage from insurance companies, and building techniques to reduce flood damage were often overlooked. In the face of mounting flood losses and escalating costs of disaster relief to the general taxpayers, the U.S. Congress created the NFIP. The intent was to reduce future flood damage through community floodplain management ordinances, and provide protection for property owners against potential losses through an insurance mechanism that requires a premium to be paid for the protection. The U.S. Congress established the NFIP on August 1, 1968, with the passage of the National Flood Insurance Act of 1968. The NFIP was broadened and modified with the passage of the Flood Disaster Protection Act of 1973 and other legislative measures. It was further modified by the National Flood Insurance Reform Act of 1994 and the Flood Insurance Reform Act of 2004. The NFIP is administered by the Federal Emergency Management Agency (FEMA), which is a component of the Department of Homeland Security (DHS). Participation in the NFIP is based on an agreement between local communities and the Federal Government. If a community adopts and enforces floodplain management regulations to reduce future flood risks to new construction and substantially improved structures in Special Flood Hazard Areas (SFHAs), the Federal Government will make flood insurance available within the community as a financial protection against flood losses. The community’s floodplain management regulations must meet or exceed criteria established in accordance with Title 44 Code of Federal Regulations (CFR) Part 60.3, Criteria for Land Management and Use. SFHAs are delineated on the community’s Flood Insurance Rate Maps (FIRMs). Under the NFIP, buildings that were built before the flood hazard was identified on the community’s FIRMs are generally referred to as “Pre-FIRM” buildings. When the NFIP was created, the U.S. Congress recognized that insurance for Pre-FIRM buildings would be prohibitively expensive if the premiums were not subsidized by the Federal Government. Congress also recognized that most of these floodprone buildings were built by individuals who did not have sufficient knowledge of the flood hazard to make informed decisions. The NFIP requires that full actuarial rates reflecting the complete flood risk be charged on all buildings constructed or substantially improved on or after
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the effective date of the initial FIRM for the community or after December 31, 1974, whichever is later. These buildings are generally referred to as “Post-FIRM” buildings.
1.2 Purpose of this Flood Insurance Study Report This Flood Insurance Study (FIS) Report revises and updates information on the existence and severity of flood hazards for the study area. The studies described in this report developed flood hazard data that will be used to establish actuarial flood insurance rates and to assist communities in efforts to implement sound floodplain management. In some states or communities, floodplain management criteria or regulations may exist that are more restrictive than the minimum Federal requirements. Contact your State NFIP Coordinator to ensure that any higher State standards are included in the community’s regulations.
1.3 Jurisdictions Included in the Flood Insurance Study Project This FIS Report covers the entire geographic area of Santa Rosa County, Florida. The jurisdictions that are included in this project area, along with the Community Identification Number (CID) for each community and the 8-digit Hydrologic Unit Codes (HUC-8) sub-basins affecting each, are shown in Table 1. The Flood Insurance Rate Map (FIRM) panel numbers that affect each community are listed. If the flood hazard data for the community is not included in this FIS Report, the location of that data is identified.
Table 1: Listing of NFIP Jurisdictions
Community CID
HUC-8 Sub-
Basin(s) Located on FIRM Panel(s)
If Not Included,
Location of Flood Hazard
Data
Gulf Breeze, City of 120275 03140105
12113C0518H1
12113C0538H 12113C0606H 12113C0608H
12113C0519H 12113C0602H 12113C0607H 12113C0626H
Jay, Town of 120339
03140104 03140304 03140305
12113C0035H
Milton, City of 120276 03140104 12113C0314G1 12113C0427H 12113C0435H
12113C0320H 12113C0431H
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Table 1: Listing of NFIP Jurisdictions
Community CID
HUC-8 Sub-
Basin(s) Located on FIRM Panel(s)
If Not Included,
Location of Flood Hazard
Data Santa Rosa County, Unincorporated Areas
120274
03140103 03140104 03140105 03140304 03140305
12113C0010G 12113C0030H 12113C0040G 12113C0055H 12113C0065H 12113C0080H 12113C0090G 12113C0105H 12113C0115G 12113C0130G 12113C0140G 12113C0155H 12113C0165H 12113C0180H 12113C0190H 12113C0205H 12113C0215H 12113C0230G 12113C0240G 12113C0255G 12113C0270H 12113C0285H 12113C0291G1
12113C0293H 12113C0305H 12113C0311H 12113C0313H 12113C0320H 12113C0335H 12113C0355H 12113C0360H 12113C0370H 12113C0405H 12113C0408H 12113C0415H 12113C0420H 12113C0427H
12113C0020G 12113C0035H 12113C0045H 12113C0060H 12113C0070H 12113C0085H 12113C0095G 12113C0110H 12113C0120G 12113C0135G 12113C0145G 12113C0160H 12113C0170H 12113C0185H 12113C0195H 12113C0210G 12113C0220G 12113C0235H 12113C0245H 12113C0260G 12113C0280G 12113C0290H 12113C0292H 12113C0294H 12113C0310H 12113C0312G1
12113C0314G1
12113C0330H 12113C0340H 12113C0345H 12113C0365H 12113C0385H 12113C0406H 12113C0410H 12113C0426H 12113C0428G1
12113C0431H
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Table 1: Listing of NFIP Jurisdictions
Community CID
HUC-8 Sub-
Basin(s) Located on FIRM Panel(s)
If Not Included,
Location of Flood Hazard
Data Santa Rosa County, Unincorporated Areas
120274
03140103 03140104 03140105 03140304 03140305
12113C0429G1
12113C0435H 12113C0445H 12113C0460H 12113C0470H 12113C0485H 12113C0495H 12113C0513G1
12113C0517G1
12113C0519H 12113C0527H 12113C0529H 12113C0532H 12113C0534G1
12113C0537H
12113C0539H 12113C0542H 12113C0544H 12113C0552H 12113C0554H 12113C0560H 12113C0562H 12113C0564H 12113C0569H 12113C0580H 12113C0586H 12113C0588H 12113C0591H 12113C0601G1
12113C0603G1
12113C0606H 12113C0608H 12113C0627H 12113C0632G1
12113C0656H
12113C0440H 12113C0455H 12113C0465H 12113C0480H 12113C0490H 12113C0510G1
12113C0514G1
12113C0518H1
12113C0526H 12113C0528H 12113C0531H 12113C0533G1
12113C0536H1
12113C0538H 12113C0541G1
12113C0543H 12113C0551H 12113C0553G1
12113C0558H 12113C0561H 12113C0563H 12113C0568H 12113C0570H 12113C0585H 12113C0587H 12113C0589H 12113C0593H 12113C0602H 12113C0604H1
12113C0607H 12113C0626H 12113C0631G1
12113C0651G1
12113C0657H
1 Panel Not Printed
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1.4 Considerations for using this Flood Insurance Study Report The NFIP encourages State and local governments to implement sound floodplain management programs. To assist in this endeavor, each FIS Report provides floodplain data, which may include a combination of the following: 10-, 4-, 2-, 1-, and 0.2-percent annual chance flood elevations (the 1% annual chance flood elevation is also referred to as the Base Flood Elevation (BFE)); delineations of the 1% annual chance and 0.2% annual chance floodplains; and 1% annual chance floodway. This information is presented on the FIRM and/or in many components of the FIS Report, including Flood Profiles, Floodway Data tables, Summary of Non-Coastal Stillwater Elevations tables, and Coastal Transect Parameters tables (not all components may be provided for a specific FIS). This section presents important considerations for using the information contained in this FIS Report and the FIRM, including changes in format and content. Figures 1, 2, and 3 present information that applies to using the FIRM with the FIS Report.
• Part or all of this FIS Report may be revised and republished at any time. In addition, part of this FIS Report may be revised by a Letter of Map Revision (LOMR), which does not involve republication or redistribution of the FIS Report. Refer to Section 6.5 of this FIS Report for information about the process to revise the FIS Report and/or FIRM.
It is, therefore, the responsibility of the user to consult with community officials by contacting the community repository to obtain the most current FIS Report components. Communities participating in the NFIP have established repositories of flood hazard data for floodplain management and flood insurance purposes. Community map repository addresses are provided in Table 31, “Map Repositories,” within this FIS Report.
• New FIS Reports are frequently developed for multiple communities, such as entire counties. A countywide FIS Report incorporates previous FIS Reports for individual communities and the unincorporated area of the county (if not jurisdictional) into a single document and supersedes those documents for the purposes of the NFIP.
The initial Countywide FIS Report for Santa Rosa County became effective on December 19, 2006. Refer to Table 28 for information about subsequent revisions to the FIRMs.
• FEMA does not impose floodplain management requirements or special insurance ratings based on Limit of Moderate Wave Action (LiMWA) delineations at this time. The LiMWA represents the approximate landward limit of the 1.5-foot breaking wave. If the LiMWA is shown on the FIRM, it is being provided by FEMA as information only. For communities that do adopt Zone VE building standards in the area defined by the LiMWA, additional Community Rating System (CRS) credits are available. Refer to Section 2.5.4 for additional information about the LiMWA.
The CRS is a voluntary incentive program that recognizes and encourages community floodplain management activities that exceed the minimum NFIP requirements. Visit the FEMA Web site at www.fema.gov/national-flood-insurance-program-community-rating-system or contact your appropriate FEMA Regional Office for more information about this program.
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• Previous FIS Reports and FIRMs may have included levees that were accredited as reducing the risk associated with the 1% annual chance flood based on the information available and the mapping standards of the NFIP at that time. For FEMA to continue to accredit the identified levees, the levees must meet the criteria of the Code of Federal Regulations, Title 44, Section 65.10 (44 CFR 65.10), titled “Mapping of Areas Protected by Levee Systems.”
Since the status of levees is subject to change at any time, the user should contact the appropriate agency for the latest information regarding levees presented in Table 9 of this FIS Report. For levees owned or operated by the U.S. Army Corps of Engineers (USACE), information may be obtained from the USACE National Levee Database (nld.usace.army.mil). For all other levees, the user is encouraged to contact the appropriate local community.
• FEMA has developed a Guide to Flood Maps (FEMA 258) and online tutorials to assist users in accessing the information contained on the FIRM. These include how to read panels and step-by-step instructions to obtain specific information. To obtain this guide and other assistance in using the FIRM, visit the FEMA Web site at www.fema.gov/online-tutorials.
The FIRM Index in Figure 1 shows the overall FIRM panel layout within Santa Rosa County, and also displays the panel number and effective date for each FIRM panel in the county. Other information shown on the FIRM Index includes community boundaries, flooding sources, watershed boundaries, and United States Geological Survey (USGS) Hydrologic Unit Code – 8 (HUC-8) codes.
NATIONAL FLOOD INSURANCE PROGRAMFLOOD INSURANCE RATE MAP INDEX
MAP NUMBER
FEMAHTTP://MSC.FEMA.GOVTHE INFORMATION DEPICTED ON THIS MAP AND SUPPORTINGDOCUMENTATION ARE ALSO AVAILABLE IN DIGITAL FORMAT AT
Map Projection:
SEE FLOOD INSURANCE STUDY FOR ADDITIONAL INFORMATION
COUNTY LOCATOR
SANTA ROSA COUNTY120274
CITY OF MILTON120276
CITY OF GULF BREEZE120275
TOWN OF JAY120339
ESCAMBIA COUNTY(AREA NOT INCLUDED)
¥¥10
£¤90
£¤98
¬«87
¬«89
¬«4
¬«87
¬«281
¬«87
Pond
Cree
k
East Bay
Escambia River
Santa Rosa Sound
Yellow River
Blackwater River
Moore Creek
Clear Creek
Escambia Bay
Sweet
water
Creek
Juniper Creek
Pensacola Bay
Dixon
Creek
Blackwater Bay
Gulf Of Mexico
Mann
ing C
reek
West
Fork
Big C
oldwa
ter Cr
eek
Big Coldwater Creek
Ates Creek
Long Branch
Turke
y Cree
k
Wolfe
Creek
Alliga
tor C
reek
Boiling Creek
Cobb Branch
Ready Creek
Mcdavid Creek
East Bay River
Malloy Branch
White River
Danle
y Bran
ch
Panther Creek
Weaver Creek
Pace Mill Creek
Wolf Creek
Pittman Creek
Bear Creek
Big Ju
niper
Creek
Crooked Creek
Buffalo M
ill Cree
kThomas
Creek
Weaver River
Dean Creek
Sevenmile Creek
Dead
River
Simpson River
Mulatto Bayou
0604H* 0608H12/19/20060603G*
0607H12/19/20060602H
12/19/2006 0651G* 0656H12/19/2006
0626H12/19/2006
0627H12/19/2006
0606H12/19/2006 0657H
12/19/20060631G*
0601G*0632G*
0514G* 0563H12/19/2006
0588H12/19/2006
0519H12/19/2006 0568H
12/19/20060539H
12/19/2006 0564H12/19/2006
0538H12/19/2006 0569H
12/19/20060518H*
0589H12/19/2006
0543H12/19/2006
0513G*
0593H12/19/2006
0544H12/19/2006
0536H* 0561H12/19/2006
0537H12/19/2006 0586H
12/19/20060517G* 0562H
12/19/20060541G* 0587H
12/19/20060542H
12/19/2006
0591H12/19/2006
0529H12/19/2006 0553G*
0528H12/19/2006 0558H
12/19/20060554H
12/19/20060533G* 0534G*
0526H12/19/2006 0551H
12/19/20060527H
12/19/2006 0552H12/19/2006
0531H12/19/2006
0532H12/19/2006
0429G**0428G**0408H12/19/2006
0406H12/19/2006 0426H
12/19/20060427H
12/19/20060431H
12/19/2006
0314G**0293H12/19/2006 0313H
12/19/20060294H
12/19/2006
0292H12/19/2006
0311H12/19/2006
0291G** 0312G**
0510G12/19/2006 0580H
12/19/20060585H
12/19/2006
0465H12/19/2006
0440H12/19/2006
0420H12/19/2006 0470H
12/19/20060490H
12/19/2006
0415H12/19/2006 0495H
12/19/20060445H
12/19/2006
0460H12/19/2006
0455H12/19/2006 0480H
12/19/2006
0405H12/19/2006
0385H12/19/2006 0485H
12/19/2006
0340H12/19/2006
0345H12/19/2006
0365H12/19/2006
0290H12/19/2006
0270H12/19/2006 0370H
12/19/20060320H
12/19/2006
0335H12/19/2006
0255G12/19/2006 0305H
12/19/2006 0330H12/19/2006
0285H12/19/2006 0355H
12/19/2006
0280G12/19/2006
0260G12/19/2006 0360H
12/19/20060310H
12/19/2006
0170H12/19/2006
0190H12/19/2006
0140G12/19/2006
0215H12/19/2006
0220G12/19/20060165H
12/19/2006 0240G12/19/2006
0245H12/19/2006
0145G12/19/2006 0195H
12/19/2006
0180H12/19/2006 0205H
12/19/2006
0130G12/19/2006 0210G
12/19/20060160H
12/19/2006 0230G12/19/2006
0155H12/19/2006
0135G12/19/2006 0235H
12/19/20060185H
12/19/2006
0090G12/19/2006
0065H12/19/2006
0045H12/19/2006 0095G
12/19/20060115G
12/19/2006
0040G12/19/2006 0120G
12/19/2006
0020G12/19/2006 0070H
12/19/2006
0085H12/19/2006
0055H12/19/2006
0035H12/19/2006 0080H
12/19/20060030H
12/19/2006 0105H12/19/2006
0110H12/19/2006
0010G12/19/2006 0060H
12/19/2006
0560H12/19/2006
0435H12/19/2006
0570H12/19/2006
0410H12/19/2006
HUC8 03140103Yellow
Watershed
HUC8 03140104BlackwaterWatershed
HUC8 03140105Pensacola Bay
Watershed
HUC8 03140305Escambia Watershed
HUC8 03140304Lower Conecuh
Watershed
1 in = 4 miles
0 1.5 3 4.5 60.75Miles
12113CIND0BMAP REVISED
0010, 0020, 0030, 0035, 0040, 0045, 0055, 0060, 0065, 0070, 0080, 0085, 0090, 0095, 0105, 0110, 0115, 0120, 0130, 0135, 0140, 0145, 0155, 0160, 0165, 0170, 0180, 0185, 0190, 0195,0205, 0210, 0215, 0220, 0230, 0235, 0240, 0245, 0255, 0260, 0270, 0280, 0285, 0290, 0292, 0293, 0294, 0305, 0310, 0311, 0313, 0320, 0330, 0335, 0340, 0345, 0355, 0360, 0365, 0370, 0385, 0405, 0406, 0408, 0410, 0415, 0420, 0426, 0427, 0431, 0435, 0440, 0445, 0455, 0460, 0465, 0470, 0480, 0485, 0490, 0495, 0519, 0526, 0527, 0528, 0529, 0531, 0532, 0537, 0538, 0539, 0542, 0543, 0544, 0551, 0552, 0554, 0558, 0560, 0561, 0562, 0563, 0564, 0568, 0569, 0570, 0580, 0585, 0586, 0587, 0588, 0589, 0591, 0593, 0602, 0606, 0607, 0608, 0626, 0627, 0656, 0657 *PANEL NOT PRINTED - OPEN WATER AREA
**PANEL NOT PRINTED - NO SPECIAL FLOOD HAZARD AREAS
and Incorporated AreasSANTA ROSA COUNTY, FLORIDAPANELS PRINTED: Florida State Plane North Zone (FIPS Zone 0903);
North American Datum 1983 HARN
Revised PreliminaryJuly 29, 2019
ATTENTION: The corporate limits shown on this FIRM Index are based on the best information available at the time of publication. As such, they may be more current than those shown on FIRM panels issued before December 19, 2016.
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Each FIRM panel may contain specific notes to the user that provide additional information regarding the flood hazard data shown on that map. However, the FIRM panel does not contain enough space to show all the notes that may be relevant in helping to better understand the information on the panel. Figure 2 contains the full list of these notes.
Figure 2: FIRM Notes to Users
NOTES TO USERS For information and questions about this map, available products associated with this FIRM including historic versions of this FIRM, how to order products, or the National Flood Insurance Program in general, please call the FEMA Map Information eXchange at 1-877-FEMA-MAP (1-877-336-2627) or visit the FEMA Flood Map Service Center website at msc.fema.gov. Available products may include previously issued Letters of Map Change, a Flood Insurance Study Report, and/or digital versions of this map. Many of these products can be ordered or obtained directly from the website. Users may determine the current map date for each FIRM panel by visiting the FEMA Flood Map Service Center website or by calling the FEMA Map Information eXchange. Communities annexing land on adjacent FIRM panels must obtain a current copy of the adjacent panel as well as the current FIRM Index. These may be ordered directly from the Flood Map Service Center at the number listed above. For community and countywide map dates, refer to Table 28 in this FIS Report. To determine if flood insurance is available in the community, contact your insurance agent or call the National Flood Insurance Program at 1-800-638-6620. PRELIMINARY FIS REPORT: FEMA maintains information about map features, such as street locations and names, in or near designated flood hazard areas. Requests to revise information in or near designated flood hazard areas may be provided to FEMA during the community review period, at the final Consultation Coordination Officer's meeting, or during the statutory 90-day appeal period. Approved requests for changes will be shown on the final printed FIRM.
The map is for use in administering the NFIP. It may not identify all areas subject to flooding, particularly from local drainage sources of small size. Consult the community map repository to find updated or additional flood hazard information. BASE FLOOD ELEVATIONS: For more detailed information in areas where Base Flood Elevations (BFEs) and/or floodways have been determined, consult the Flood Profiles and Floodway Data and/or Summary of Non-Coastal Stillwater Elevations tables within this FIS Report. Use the flood elevation data within the FIS Report in conjunction with the FIRM for construction and/or floodplain management. Coastal Base Flood Elevations shown on the map apply only landward of 0.0' North American Vertical Datum of 1988 (NAVD88). Coastal flood elevations are also provided in the Coastal Transect Parameters table in the FIS Report for this jurisdiction. Elevations shown in the Coastal Transect Parameters table should be used for construction and/or floodplain management purposes when they are higher than the elevations shown on the FIRM.
Figure 2: FIRM Notes to Users
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FLOODWAY INFORMATION: Boundaries of the floodways were computed at cross sections and interpolated between cross sections. The floodways were based on hydraulic considerations with regard to requirements of the National Flood Insurance Program. Floodway widths and other pertinent floodway data are provided in the FIS Report for this jurisdiction. FLOOD CONTROL STRUCTURE INFORMATION: Certain areas not in Special Flood Hazard Areas may be protected by flood control structures. Refer to Section 4.3 "Non-Levee Flood Protection Measures" of this FIS Report for information on flood control structures for this jurisdiction. PROJECTION INFORMATION: The projection used in the preparation of the map was Florida State Plane North Zone (FIPS Zone 0903), North American Datum of 1983 (NAD83). The horizontal datum was NAD83. Differences in datum, spheroid, projection or State Plane zones used in the production of FIRMs for adjacent jurisdictions may result in slight positional differences in map features across jurisdiction boundaries. These differences do not affect the accuracy of the FIRM. ELEVATION DATUM: Flood elevations on the FIRM are referenced to the North American Vertical Datum of 1988. These flood elevations must be compared to structure and ground elevations referenced to the same vertical datum. For information regarding conversion between the National Geodetic Vertical Datum of 1929 and the North American Vertical Datum of 1988, visit the National Geodetic Survey website at www.ngs.noaa.gov/ or contact the National Geodetic Survey at the following address: NGS Information Services NOAA, N/NGS12 National Geodetic Survey SSMC-3, #9202 1315 East-West Highway Silver Spring, Maryland 20910-3282 (301) 713-3242 Local vertical monuments may have been used to create the map. To obtain current monument information, please contact the appropriate local community listed in Table 31 of this FIS Report. BASE MAP INFORMATION: Base map information shown on the FIRM was provided by Florida Department of Transportation (FDOT). This information was derived from digital orthophotography at a 0.9 foot resolution from photography dated 2013. For information about base maps, refer to Section 6.2 “Base Map” in this FIS Report. The map reflects more detailed and up-to-date stream channel configurations than those shown on the previous FIRM for this jurisdiction. The floodplains and floodways that were transferred from the previous FIRM may have been adjusted to conform to these new stream channel configurations. As a result, the Flood Profiles and Floodway Data tables may reflect stream channel distances that differ from what is shown on the map. Corporate limits shown on the map are based on the best data available at the time of publication. Because changes due to annexations or de-annexations may have occurred after the map was published, map users should contact appropriate community officials to verify current corporate limit locations.
Figure 2: FIRM Notes to Users
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NOTES FOR FIRM INDEX REVISIONS TO INDEX: As new studies are performed and FIRM panels are updated within Santa Rosa County, FL, corresponding revisions to the FIRM Index will be incorporated within the FIS Report to reflect the effective dates of those panels. Please refer to Table 28 of this FIS Report to determine the most recent FIRM revision date for each community. The most recent FIRM panel effective date will correspond to the most recent index date. SPECIAL NOTES FOR SPECIFIC FIRM PANELS This Notes to Users section was created specifically for Santa Rosa County, FL, effective TBD. COASTAL BARRIER RESOURCES SYSTEM (CBRS): This map includes approximate boundaries of the CBRS for informational purposes only. Flood insurance is not available within CBRS areas for structures that are newly built or substantially improved on or after the date(s) indicated on the map. For more information see www.fws.gov/cbra/, the FIS Report, or call the U.S. Fish and Wildlife Service Customer Service Center at 1-800-344-WILD. LIMIT OF MODERATE WAVE ACTION: Zone AE has been divided by a Limit of Moderate Wave Action (LiMWA). The LiMWA represents the approximate landward limit of the 1.5-foot breaking wave. The effects of wave hazards between Zone VE and the LiMWA (or between the shoreline and the LiMWA for areas where Zone VE is not identified) will be similar to, but less severe than, those in Zone VE. FLOOD RISK REPORT: A Flood Risk Report (FRR) may be available for many of the flooding sources and communities referenced in this FIS Report. The FRR is provided to increase public awareness of flood risk by helping communities identify the areas within their jurisdictions that have the greatest risks. Although non-regulatory, the information provided within the FRR can assist communities in assessing and evaluating mitigation opportunities to reduce these risks. It can also be used by communities developing or updating flood risk mitigation plans. These plans allow communities to identify and evaluate opportunities to reduce potential loss of life and property. However, the FRR is not intended to be the final authoritative source of all flood risk data for a project area; rather, it should be used with other data sources to paint a comprehensive picture of flood risk.
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Each FIRM panel contains an abbreviated legend for the features shown on the maps. However, the FIRM panel does not contain enough space to show the legend for all map features. Figure 3 shows the full legend of all map features. Note that not all of these features may appear on the FIRM panels in Santa Rosa County.
Figure 3: Map Legend for FIRM
SPECIAL FLOOD HAZARD AREAS: The 1% annual chance flood, also known as the base flood or 100-year flood, has a 1% chance of happening or being exceeded each year. Special Flood Hazard Areas are subject to flooding by the 1% annual chance flood. The Base Flood Elevation is the water surface elevation of the 1% annual chance flood. The floodway is the channel of a stream plus any adjacent floodplain areas that must be kept free of encroachment so that the 1% annual chance flood can be carried without substantial increases in flood heights. See note for specific types. If the floodway is too narrow to be shown, a note is shown.
Special Flood Hazard Areas subject to inundation by the 1% annual chance flood (Zones A, AE, AH, AO, AR, A99, V and VE)
Zone A The flood insurance rate zone that corresponds to the 1% annual chance floodplains. No base (1% annual chance) flood elevations (BFEs) or depths are shown within this zone.
Zone AE The flood insurance rate zone that corresponds to the 1% annual chance floodplains. Base flood elevations derived from the hydraulic analyses are shown within this zone.
Zone AH The flood insurance rate zone that corresponds to the areas of 1% annual chance shallow flooding (usually areas of ponding) where average depths are between 1 and 3 feet. Whole-foot BFEs derived from the hydraulic analyses are shown at selected intervals within this zone.
Zone AO The flood insurance rate zone that corresponds to the areas of 1% annual chance shallow flooding (usually sheet flow on sloping terrain) where average depths are between 1 and 3 feet. Average whole-foot depths derived from the hydraulic analyses are shown within this zone.
Zone AR The flood insurance rate zone that corresponds to areas that were formerly protected from the 1% annual chance flood by a flood control system that was subsequently decertified. Zone AR indicates that the former flood control system is being restored to provide protection from the 1% annual chance or greater flood.
Zone A99 The flood insurance rate zone that corresponds to areas of the 1% annual chance floodplain that will be protected by a Federal flood protection system where construction has reached specified statutory milestones. No base flood elevations or flood depths are shown within this zone.
Zone V The flood insurance rate zone that corresponds to the 1% annual chance coastal floodplains that have additional hazards associated with storm waves. Base flood elevations are not shown within this zone.
Zone VE Zone VE is the flood insurance rate zone that corresponds to the 1% annual chance coastal floodplains that have additional hazards associated with storm waves. Base flood elevations derived from the coastal analyses are shown within this zone as static whole-foot elevations that apply throughout the zone.
Figure 3: Map Legend for FIRM
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Regulatory Floodway determined in Zone AE.
Non-encroachment zone (see Section 2.4 of this FIS Report for more information)
FLOOD INSURANCE IS NOT AVAILABLE FOR STRUCTURES NEWLY BUILT OR SUBSTANTIALLY IMPROVED ON OR AFTER APRIL 8, 1987, IN THE DESIGNATED COLORADO RIVER FLOODWAY
The Colorado River Floodway was established by Congress in the Colorado River Floodway Protection Act of 1986, Public Law 99-450 (100 Statute 1129). The Act imposes certain restrictions within the Floodway.
OTHER AREAS OF FLOOD HAZARD
Shaded Zone X: Areas of 0.2% annual chance flood hazards and areas of 1% annual chance flood hazards with average depths of less than 1 foot or with drainage areas less than 1 square mile.
Future Conditions 1% Annual Chance Flood Hazard – Zone X: The flood insurance rate zone that corresponds to the 1% annual chance floodplains that are determined based on future-conditions hydrology. No base flood elevations or flood depths are shown within this zone.
Area with Reduced Flood Risk due to Levee: Areas where an accredited levee, dike, or other flood control structure has reduced the flood risk from the 1% annual chance flood. See Notes to Users for important information.
OTHER AREAS
Zone D (Areas of Undetermined Flood Hazard): The flood insurance rate zone that corresponds to unstudied areas where flood hazards are undetermined, but possible.
Unshaded Zone X: Areas of minimal flood hazard.
FLOOD HAZARD AND OTHER BOUNDARY LINES
(ortho) (vector)
Flood Zone Boundary (white line on ortho-photography-based mapping; gray line on vector-based mapping)
Limit of Study
Jurisdiction Boundary
Limit of Moderate Wave Action (LiMWA): Indicates the inland limit of the area affected by waves greater than 1.5 feet
NO SCREEN
Figure 3: Map Legend for FIRM
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GENERAL STRUCTURES
Aqueduct Channel Culvert
Storm Sewer
Channel, Culvert, Aqueduct, or Storm Sewer
__________ Dam Jetty Weir
Dam, Jetty, Weir
Levee, Dike, or Floodwall
Bridge
Bridge
COASTAL BARRIER RESOURCES SYSTEM (CBRS) AND OTHERWISE PROTECTED AREAS (OPA): CBRS areas and OPAs are normally located within or adjacent to Special Flood Hazard Areas. See Notes to Users for important information.
CBRS AREA 09/30/2009
Coastal Barrier Resources System Area: Labels are shown to clarify where this area shares a boundary with an incorporated area or overlaps with the floodway.
OTHERWISE PROTECTED AREA
09/30/2009
Otherwise Protected Area
REFERENCE MARKERS
River mile Markers
CROSS SECTION & TRANSECT INFORMATION
Lettered Cross Section with Regulatory Water Surface Elevation (BFE)
Numbered Cross Section with Regulatory Water Surface Elevation (BFE)
Unlettered Cross Section with Regulatory Water Surface Elevation (BFE)
Coastal Transect
Figure 3: Map Legend for FIRM
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Profile Baseline: Indicates the modeled flow path of a stream and is shown on FIRM panels for all valid studies with profiles or otherwise established base flood elevation.
Coastal Transect Baseline: Used in the coastal flood hazard model to represent the 0.0-foot elevation contour and the starting point for the transect and the measuring point for the coastal mapping.
Base Flood Elevation Line
ZONE AE (EL 16) Static Base Flood Elevation value (shown under zone label)
ZONE AO (DEPTH 2) Zone designation with Depth
ZONE AO (DEPTH 2)
(VEL 15 FPS) Zone designation with Depth and Velocity
BASE MAP FEATURES
Missouri Creek River, Stream or Other Hydrographic Feature
Interstate Highway
U.S. Highway
State Highway
County Highway
MAPLE LANE
Street, Road, Avenue Name, or Private Drive if shown on Flood Profile
RAILROAD
Railroad
Horizontal Reference Grid Line
Horizontal Reference Grid Ticks
Secondary Grid Crosshairs
Land Grant Name of Land Grant
7 Section Number
R. 43 W. T. 22 N. Range, Township Number
4276000mE Horizontal Reference Grid Coordinates (UTM)
365000 FT Horizontal Reference Grid Coordinates (State Plane)
80° 16’ 52.5” Corner Coordinates (Latitude, Longitude)
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SECTION 2.0 – FLOODPLAIN MANAGEMENT APPLICATIONS
2.1 Floodplain Boundaries To provide a national standard without regional discrimination, the 1% annual chance (100-year) flood has been adopted by FEMA as the base flood for floodplain management purposes. The 0.2% annual chance (500-year) flood is employed to indicate additional areas of flood hazard in the community. Each flooding source included in the project scope has been studied and mapped using professional engineering and mapping methodologies that were agreed upon by FEMA and Santa Rosa County as appropriate to the risk level. Flood risk is evaluated based on factors such as known flood hazards and projected impact on the built environment. Engineering analyses were performed for each studied flooding source to calculate its 1% annual chance flood elevations; elevations corresponding to other floods (e.g. 10-, 4-, 2-, 0.2-percent annual chance, etc.) may have also been computed for certain flooding sources. Engineering models and methods are described in detail in Section 5.0 of this FIS Report. The modeled elevations at cross sections were used to delineate the floodplain boundaries on the FIRM; between cross sections, the boundaries were interpolated using elevation data from various sources. More information on specific mapping methods is provided in Section 6.0 of this FIS Report. Depending on the accuracy of available topographic data (Table 23), study methodologies employed (Section 5.0), and flood risk, certain flooding sources may be mapped to show both the 1% and 0.2% annual chance floodplain boundaries, regulatory water surface elevations (BFEs), and/or a regulatory floodway. Similarly, other flooding sources may be mapped to show only the 1% annual chance floodplain boundary on the FIRM, without published water surface elevations. In cases where the 1% and 0.2% annual chance floodplain boundaries are close together, only the 1% annual chance floodplain boundary is shown on the FIRM. Figure 3, “Map Legend for FIRM”, describes the flood zones that are used on the FIRMs to account for the varying levels of flood risk that exist along flooding sources within the project area. Table 2 and Table 3 indicate the flood zone designations for each flooding source and each community within Santa Rosa County, respectively.
Table 2, “Flooding Sources Included in this FIS Report,” lists each flooding source, including its study limits, affected communities, mapped zone on the FIRM, and the completion date of its engineering analysis from which the flood elevations on the FIRM and in the FIS Report were derived. Descriptions and dates for the latest hydrologic and hydraulic analyses of the flooding sources are shown in Table 13. Floodplain boundaries for these flooding sources are shown on the FIRM (published separately) using the symbology described in Figure 3. On the map, the 1% annual chance floodplain corresponds to the SFHAs. The 0.2% annual chance floodplain shows areas that, although out of the regulatory floodplain, are still subject to flood hazards. Small areas within the floodplain boundaries may lie above the flood elevations but cannot be shown due to limitations of the map scale and/or lack of detailed topographic data. The procedures to remove these areas from the SFHA are described in Section 6.5 of this FIS Report.
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Table 2: Flooding Sources Included in this FIS Report
Flooding Source Community Downstream
Limit Upstream Limit HUC-8 Sub-
Basin(s)
Length (mi) (streams or coastlines)
Area (mi2) (estuaries or
ponding) Floodway
(Y/N)
Zone shown on
FIRM Date of
Analysis
Beale Creek Santa Rosa County, Unincorporated Areas
At confluence Escambia River
Approximately 800 feet southwest of Curtis Road
03140305 3.8 N AE 2012
Big Coldwater Creek
Santa Rosa County, Unincorporated Areas
At confluence with Blackwater River
Approximately 0.65 miles northwest of Steel Bridge Road
03140104 7.4 N AE 2018
Big Coldwater Creek
Santa Rosa County, Unincorporated Areas
Approximately 0.65 miles northwest of Steel Bridge Road
At confluence with East Fork Big Coldwater Creek and West Fork Big Coldwater Creek
03140104 4.1 N AE 2012
Blackwater Bay Santa Rosa County, Unincorporated Areas Entire Coastline Entire Coastline 03140103
03140105 26.8 N AE, VE 2015
Blackwater River City of Milton, Santa Rosa County, Unincorporated Areas
At Interstate 10 Approximately 620 feet downstream Deaton Bridge Road
03140104 03140105 19.0 Y AE 2012
Blackwater River City of Milton, Santa Rosa County, Unincorporated Areas
Approximately 620 feet downstream Deaton Bridge Road
At County Boundary 03140104 03140105 14.6 N AE 2012
Bray Mill Creek Santa Rosa County, Unincorporated Areas, Town of Jay
At confluence with Escambia River
At Town of Jay Boundary
03140304 03140305 3.4 nN A 2012
Clear Creek Santa Rosa County, Unincorporated Areas
At confluence with Blackwater River
Just upstream of Blackwater Heritage State Trail
03140104 4.0 N AE 2018
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Table 2: Flooding Sources Included in this FIS Report
Flooding Source Community Downstream
Limit Upstream Limit HUC-8 Sub-
Basin(s)
Length (mi) (streams or coastlines)
Area (mi2) (estuaries or
ponding) Floodway
(Y/N)
Zone shown on
FIRM Date of
Analysis
Clear Creek Santa Rosa County, Unincorporated Areas
Just upstream of Blackwater Heritage State Trail
Approximately 1,400 feet southeast of Forrest Hills Rd
03140104 5.9 N AE 2012
East Bay Santa Rosa County, Unincorporated Areas Entire Coastline Entire Coastline 03140105 33.0 N AE, VE 2015
East Bay River Santa Rosa County, Unincorporated Areas
At confluence with East Bay At County Boundary 03140105 7.6 Y AE 1984
East Fork Big Coldwater Creek
Santa Rosa County, Unincorporated Areas
At confluence with Big Coldwater Creek and West Fork Big Coldwater Creek
Approximately 0.5 miles east of Gordon Land Rd.
03140104 7.3 N AE 2012
Escambia Bay Santa Rosa County, Unincorporated Areas Entire Coastline Entire Coastline 03140105 25.5 N AE, VE 2015
Escambia River Santa Rosa County, Unincorporated Areas At US 10 Just upstream
Highway 4
03140105 03140304 03140305
51.4 Y AE 2005
Escambia River Santa Rosa County, Unincorporated Areas
Just upstream Highway 4
At Florida/Alabama state line
03140105 03140304 03140305
7.0 N A 2005
Gulf of Mexico Santa Rosa County, Unincorporated Areas Entire Coastline Entire Coastline 03140105 8.6 N AE, VE 2015
Holley by the Sea Santa Rosa County, Unincorporated Areas
Entire Watershed Entire Watershed 03140105 2.1 N AE 2016
Holley by the Sea Santa Rosa County, Unincorporated Areas
Entire Watershed Entire Watershed 03140105 2.1 N A 2016
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Table 2: Flooding Sources Included in this FIS Report
Flooding Source Community Downstream
Limit Upstream Limit HUC-8 Sub-
Basin(s)
Length (mi) (streams or coastlines)
Area (mi2) (estuaries or
ponding) Floodway
(Y/N)
Zone shown on
FIRM Date of
Analysis
Jacobs Creek Santa Rosa County, Unincorporated Areas
At confluence with Pace Mill Creek
At Becky Ln 03140105 1.0 N AE 2012
Juniper Creek Santa Rosa County, Unincorporated Areas
At confluence with West Fork Big Coldwater Creek
Approximately 630 feet south of Letcher Block Road
03140104 10.5 N AE 2012
Juniper Creek Santa Rosa County, Unincorporated Areas 03140104 N A 2012
Long Branch Santa Rosa County, Unincorporated Areas
At confluence with Pond Creek
At Long Branch Pond 03140104 2.7 N A 2012
Malloy Branch Santa Rosa County, Unincorporated Areas
At confluence with West Fork Big Coldwater Creek
At Town of Jay Boundary 03140104 5.3 N A 2012
Manning Creek Santa Rosa County, Unincorporated Areas
At confluence with West Fork Big Coldwater Creek
At Van Jernigan Road 03140104 5.4 N AE 2012
Pace Mill Creek Santa Rosa County, Unincorporated Areas
At confluence with Escambia Bay
At Chumuckla Hwy 03140105 03140305 5.3 Y AE 2005
Pensacola Bay City of Gulf Breeze, Santa Rosa County, Unincorporated Areas
Entire Coastline Entire Coastline 03140105 11.4 N AE, VE 2015
Pond Creek Santa Rosa County, Unincorporated Areas
At Willard Norris Road
Just upstream Fort Acre Pond 03140104 16.4 N AE 2012
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Table 2: Flooding Sources Included in this FIS Report
Flooding Source Community Downstream
Limit Upstream Limit HUC-8 Sub-
Basin(s)
Length (mi) (streams or coastlines)
Area (mi2) (estuaries or
ponding) Floodway
(Y/N)
Zone shown on
FIRM Date of
Analysis
Pond Creek City of Milton, Santa Rosa County, Unincorporated Areas
At confluence with Blackwater River
At Willard Norris Road 03140104 13.2 Y AE 2005
Reader Creek Santa Rosa County, Unincorporated Areas
At confluence with Pond Creek
At Fairway Drive 03140104 3.6 N AE 2012
Rocky Creek Santa Rosa County, Unincorporated Areas
At Confluence with Escambia River
At Rowe Trail 03140305 3.3 N AE 2012
Santa Rosa Sound
City of Gulf Breeze, Santa Rosa County, Unincorporated Areas
Entire Coastline Entire Coastline 03140105 36.2 N AE, VE 2015
Unnamed Tributary to Beale Creek
Santa Rosa County, Unincorporated Areas
At confluence with Escambia River
Approximately 300 feet north of Highway 4
03140305 1.0 N AE 2012
Unnamed Tributary to Bray Mill Creek
Santa Rosa County, Unincorporated Areas
At confluence with Bray Mill Creek
Approximately 3,000 feet north of Highway 4
03140304 0.23 N A 2012
Unnamed Tributary to Escambia River
Santa Rosa County, Unincorporated Areas
At confluence with Big Coldwater Creek and East Fork Big Coldwater Creek
Approximately 1,300 feet southwest of County Mill Road
03140305 2.6 N A 2012
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Table 2: Flooding Sources Included in this FIS Report
Flooding Source Community Downstream
Limit Upstream Limit HUC-8 Sub-
Basin(s)
Length (mi) (streams or coastlines)
Area (mi2) (estuaries or
ponding) Floodway
(Y/N)
Zone shown on
FIRM Date of
Analysis
West Fork Big Coldwater Creek
Santa Rosa County, Unincorporated Areas
At confluence with Big Coldwater Creek and East Fork Big Coldwater Creek
Just upstream confluence with Juniper Creek
03140104 9.6 N AE 2012
West Fork Big Coldwater Creek
Santa Rosa County, Unincorporated Areas
Just upstream confluence with Juniper Creek
At confluence with Malloy Branch 03140104 7.2 N A 2012
Yellow River Santa Rosa County, Unincorporated Areas
At confluence with Escambia River
Approximately 300 feet north of Highway 4
03140103 03140105 20.1 Y AE 2012
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2.2 Floodways Encroachment on floodplains, such as structures and fill, reduces flood-carrying capacity, increases flood heights and velocities, and increases flood hazards in areas beyond the encroachment itself. One aspect of floodplain management involves balancing the economic gain from floodplain development against the resulting increase in flood hazard. For purposes of the NFIP, a floodway is used as a tool to assist local communities in balancing floodplain development against increasing flood hazard. With this approach, the area of the 1% annual chance floodplain on a river is divided into a floodway and a floodway fringe based on hydraulic modeling. The floodway is the channel of a stream, plus any adjacent floodplain areas, that must be kept free of encroachment in order to carry the 1% annual chance flood. The floodway fringe is the area between the floodway and the 1% annual chance floodplain boundaries where encroachment is permitted. The floodway must be wide enough so that the floodway fringe could be completely obstructed without increasing the water surface elevation of the 1% annual chance flood more than 1 foot at any point. Typical relationships between the floodway and the floodway fringe and their significance to floodplain development are shown in Figure 4. To participate in the NFIP, Federal regulations require communities to limit increases caused by encroachment to 1.0 foot, provided that hazardous velocities are not produced. The floodways in this project are presented to local agencies as minimum standards that can be adopted directly or that can be used as a basis for additional floodway projects.
Figure 4: Floodway Schematic
Floodway widths presented in this FIS Report and on the FIRM were computed at cross sections. Between cross sections, the floodway boundaries were interpolated. For certain stream segments,
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floodways were adjusted so that the amount of floodwaters conveyed on each side of the floodplain would be reduced equally. The results of the floodway computations have been tabulated for selected cross sections and are shown in Table 24, “Floodway Data.” All floodways that were developed for this Flood Risk Project are shown on the FIRM using the symbology described in Figure 3. In cases where the floodway and l% annual chance floodplain boundaries are either close together or collinear, only the floodway boundary has been shown on the FIRM. For information about the delineation of floodways on the FIRM, refer to Section 6.3.
2.3 Base Flood Elevations The hydraulic characteristics of flooding sources were analyzed to provide estimates of the elevations of floods of the selected recurrence intervals. The Base Flood Elevation (BFE) is the elevation of the 1% annual chance flood. These BFEs are most commonly rounded to the whole foot, as shown on the FIRM, but in certain circumstances or locations they may be rounded to 0.1 foot. Cross section lines shown on the FIRM may also be labeled with the BFE rounded to 0.1 foot. Whole-foot BFEs derived from engineering analyses that apply to coastal areas, areas of ponding, or other static areas with little elevation change may also be shown at selected intervals on the FIRM. Cross sections with BFEs shown on the FIRM correspond to the cross sections shown in the Floodway Data table and Flood Profiles in this FIS Report. BFEs are primarily intended for flood insurance rating purposes. For construction and/or floodplain management purposes, users are cautioned to use the flood elevation data presented in this FIS Report in conjunction with the data shown on the FIRM.
2.4 Non-Encroachment Zones Some States and communities use non-encroachment zones to manage floodplain development. For flooding sources with medium flood risk, field surveys are often not collected and surveyed bridge and culvert geometry is not developed. Standard hydrologic and hydraulic analyses are still performed to determine BFEs in these areas. However, floodways are not typically determined, since specific channel profiles are not developed. To assist communities with managing floodplain development in these areas, a “non-encroachment zone” may be provided. While not a FEMA designated floodway, the non-encroachment zone represents that area around the stream that should be reserved to convey the 1% annual chance flood event. As with a floodway, all surcharges must fall within the acceptable range in the non-encroachment zone. General setbacks can be used in areas of lower risk (e.g. unnumbered Zone A), but these are not considered sufficient where unnumbered Zone A is replaced by Zone AE. The NFIP requires communities to ensure that any development in a non-encroachment area causes no increase in BFEs. Communities must generally prohibit development within the area defined by the non-encroachment width to meet the NFIP requirement. Non-encroachment determinations may be delineated where it is not possible to delineate floodways because specific channel profiles with bridge and culvert geometry were not developed. Any non-encroachment determinations for this Flood Risk Project have been tabulated for selected cross sections and are shown in Table 25, “Flood Hazard and Non-Encroachment Data for Selected Streams.” Areas for which non-encroachment zones are provided show BFEs and the 1% annual chance floodplain boundaries mapped as zone AE on the FIRM but no floodways.
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2.5 Coastal Flood Hazard Areas For most areas along rivers, streams, and small lakes, BFEs and floodplain boundaries are based on the amount of water expected to enter the area during a 1% annual chance flood and the geometry of the floodplain. Floods in these areas are typically caused by storm events. However, for areas on or near ocean coasts, large rivers, or large bodies of water, BFE and floodplain boundaries may need to be based on additional components, including storm surges and waves. Communities on or near ocean coasts face flood hazards caused by offshore seismic events as well as storm events. Coastal flooding sources that are included in this Flood Risk Project are shown in Table 2.
2.5.1 Water Elevations and the Effects of Waves Specific terminology is used in coastal analyses to indicate which components have been included in evaluating flood hazards. The stillwater elevation (SWEL or still water level) is the surface of the water resulting from astronomical tides, storm surge, and freshwater inputs, but excluding wave setup contribution or the effects of waves.
• Astronomical tides are periodic rises and falls in large bodies of water caused by the rotation of the earth and by the gravitational forces exerted by the earth, moon and sun.
• Storm surge is the additional water depth that occurs during large storm events. These events can bring air pressure changes and strong winds that force water up against the shore.
• Freshwater inputs include rainfall that falls directly on the body of water, runoff from surfaces and overland flow, and inputs from rivers.
The 1% annual chance stillwater elevation is the stillwater elevation that has been calculated for a storm surge from a 1% annual chance storm. The 1% annual chance storm surge can be determined from analyses of tidal gage records, statistical study of regional historical storms, or other modeling approaches. Stillwater elevations for storms of other frequencies can be developed using similar approaches. The total stillwater elevation (also referred to as the mean water level) is the stillwater elevation plus wave setup contribution but excluding the effects of waves.
• Wave setup is the increase in stillwater elevation at the shoreline caused by the reduction of waves in shallow water. It occurs as breaking wave momentum is transferred to the water column.
Like the stillwater elevation, the total stillwater elevation is based on a storm of a particular frequency, such as the 1% annual chance storm. Wave setup is typically estimated using standard engineering practices or calculated using models, since tidal gages are often sited in areas sheltered from wave action and do not capture this information. Coastal analyses may examine the effects of overland waves by analyzing storm-induced erosion, overland wave propagation, wave runup, and/or wave overtopping.
• Storm-induced erosion is the modification of existing topography by erosion caused by a specific storm event, as opposed to general erosion that occurs at a more constant rate.
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• Overland wave propagation describes the combined effects of variation in ground elevation, vegetation, and physical features on wave characteristics as waves move onshore.
• Wave runup is the uprush of water from wave action on a shore barrier. It is a function of the roughness and geometry of the shoreline at the point where the stillwater elevation intersects the land.
• Wave overtopping refers to wave runup that occurs when waves pass over the crest of a barrier.
Figure 5: Wave Runup Transect Schematic
2.5.2 Floodplain Boundaries and BFEs for Coastal Areas For coastal communities along the Atlantic and Pacific Oceans, the Gulf of Mexico, the Great Lakes, and the Caribbean Sea, flood hazards must take into account how storm surges, waves, and extreme tides interact with factors such as topography and vegetation. Storm surge and waves must also be considered in assessing flood risk for certain communities on rivers or large inland bodies of water. Beyond areas that are affected by waves and tides, coastal communities can also have riverine floodplains with designated floodways, as described in previous sections. Floodplain Boundaries In many coastal areas, storm surge is the principle component of flooding. The extent of the 1% annual chance floodplain in these areas is derived from the total stillwater elevation (stillwater elevation including storm surge plus wave setup) for the 1% annual chance storm. The methods that were used for calculation of total stillwater elevations for coastal areas are described in Section 5.3 of this FIS Report. Location of total stillwater elevations for coastal areas are shown in Figure 8, “1% Annual Chance Total Stillwater Levels for Coastal Areas.” In some areas, the 1% annual chance floodplain is determined based on the limit of wave runup or wave overtopping for the 1% annual chance storm surge. The methods that were used for calculation of wave hazards are described in Section 5.3 of this FIS Report.
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Table 26 presents the types of coastal analyses that were used in mapping the 1% annual chance floodplain in coastal areas. Coastal BFEs Coastal BFEs are calculated as the total stillwater elevation (stillwater elevation including storm surge plus wave setup) for the 1% annual chance storm plus the additional flood hazard from overland wave effects (storm-induced erosion, overland wave propagation, wave runup and wave overtopping). Where they apply, coastal BFEs are calculated along transects extending from offshore to the limit of coastal flooding onshore. Results of these analyses are accurate until local topography, vegetation, or development type and density within the community undergoes major changes. Parameters that were included in calculating coastal BFEs for each transect included in this FIS Report are presented in Table 17, “Coastal Transect Parameters.” The locations of transects are shown in Figure 9, “Transect Location Map.” More detailed information about the methods used in coastal analyses and the results of intermediate steps in the coastal analyses are presented in Section 5.3 of this FIS Report. Additional information on specific mapping methods is provided in Section 6.4 of this FIS Report.
2.5.3 Coastal High Hazard Areas Certain areas along the open coast and other areas may have higher risk of experiencing structural damage caused by wave action and/or high-velocity water during the 1% annual chance flood. These areas will be identified on the FIRM as Coastal High Hazard Areas.
• Coastal High Hazard Area (CHHA) is a SFHA extending from offshore to the inland limit of the primary frontal dune (PFD) or any other area subject to damages caused by wave action and/or high-velocity water during the 1% annual chance flood.
• Primary Frontal Dune (PFD) is a continuous or nearly continuous mound or ridge of sand with relatively steep slopes immediately landward and adjacent to the beach. The PFD is subject to erosion and overtopping from high tides and waves during major coastal storms.
CHHAs are designated as “V” zones (for “velocity wave zones”) and are subject to more stringent regulatory requirements and a different flood insurance rate structure. The areas of greatest risk are shown as VE on the FIRM. Zone VE is further subdivided into elevation zones and shown with BFEs on the FIRM. The landward limit of the PFD occurs at a point where there is a distinct change from a relatively steep slope to a relatively mild slope; this point represents the landward extension of Zone VE. Areas of lower risk in the CHHA are designated with Zone V on the FIRM. More detailed information about the identification and designation of Zone VE is presented in Section 6.4 of this FIS Report. Areas that are not within the CHHA but are SFHAs may still be impacted by coastal flooding and damaging waves; these areas are shown as “A” zones on the FIRM. Figure 6, “Coastal Transect Schematic,” illustrates the relationship between the base flood elevation, the 1% annual chance stillwater elevation, and the ground profile as well as the location
26
of the Zone VE and Zone AE areas in an area without a PFD subject to overland wave propagation. This figure also illustrates energy dissipation and regeneration of a wave as it moves inland.
Figure 6: Coastal Transect Schematic
Methods used in coastal analyses in this Flood Risk Project are presented in Section 5.3 and mapping methods are provided in Section 6.4 of this FIS Report. Coastal floodplains are shown on the FIRM using the symbology described in Figure 3, “Map Legend for FIRM.” In many cases, the BFE on the FIRM is higher than the stillwater elevations shown in Table 17 due to the presence of wave effects. The higher elevation should be used for construction and/or floodplain management purposes.
2.5.4 Limit of Moderate Wave Action Laboratory tests and field investigations have shown that wave heights as little as 1.5 feet can cause damage to and failure of typical Zone AE building construction. Wood-frame, light gage steel, or masonry walls on shallow footings or slabs are subject to damage when exposed to waves less than 3 feet in height. Other flood hazards associated with coastal waves (floating debris, high velocity flow, erosion, and scour) can also damage Zone AE construction. Therefore, a LiMWA boundary may be shown on the FIRM as an informational layer to assist coastal communities in safe rebuilding practices. The LiMWA represents the approximate landward limit of the 1.5-foot breaking wave. The location of the LiMWA relative to Zone VE and Zone AE is shown in Figure 6. The effects of wave hazards in Zone AE between Zone VE (or the shoreline where Zone VE is not identified) and the limit of the LiMWA boundary are similar to, but less severe than, those in Zone VE where 3-foot or greater breaking waves are projected to occur during the 1% annual chance flooding event. Communities are therefore encouraged to adopt and enforce more stringent floodplain management requirements than the minimum NFIP requirements in the LiMWA. The NFIP Community Rating System provides credits for these actions.
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Where wave runup elevations dominate over wave heights, there is no evidence to date of significant damage to residential structures by runup depths less than 3 feet. Examples of these areas include areas with steeply sloped beaches, bluffs, or flood protection structures that lie parallel to the shore. In these areas, the FIRM shows the LiMWA immediately landward of the VE/AE boundary. Similarly, in areas where the zone VE designation is based on the presence of a primary frontal dune or wave overtopping, the LiMWA is delineated immediately landward of the Zone VE/AE boundary.
SECTION 3.0 – INSURANCE APPLICATIONS
3.1 National Flood Insurance Program Insurance Zones For flood insurance applications, the FIRM designates flood insurance rate zones as described in Figure 3, “Map Legend for FIRM.” Flood insurance zone designations are assigned to flooding sources based on the results of the hydraulic or coastal analyses. Insurance agents use the zones shown on the FIRM and depths and base flood elevations in this FIS Report in conjunction with information on structures and their contents to assign premium rates for flood insurance policies. The 1% annual chance floodplain boundary corresponds to the boundary of the areas of special flood hazards (e.g. Zones A, AE, V, VE, etc.), and the 0.2% annual chance floodplain boundary corresponds to the boundary of areas of additional flood hazards. Table 3 lists the flood insurance zones in Santa Rosa County.
Table 3: Flood Zone Designations by Community
Community Flood Zone(s)
Gulf Breeze, City of AE, VE, AO, X
Jay, Town of A, X
Milton, City of AE, X
Santa Rosa County, Unincorporated Areas A, AE, VE, X
3.2 Coastal Barrier Resources System The Coastal Barrier Resources Act (CBRA) of 1982 was established by Congress to create areas along the Atlantic and Gulf coasts and the Great Lakes, where restrictions for Federal financial assistance including flood insurance are prohibited. In 1990, Congress passed the Coastal Barrier Improvement Act (CBIA), which increased the extent of areas established by the CBRA and added “Otherwise Protected Areas” (OPA) to the system. These areas are collectively referred to as the John. H Chafee Coastal Barrier Resources System (CBRS). The CBRS boundaries that have been identified in the project area are in Table 4, “Coastal Barrier Resource System Information.”
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Table 4: Coastal Barrier Resources System Information
Primary Flooding Source CBRS/OPA Type Date CBRS Area
Established FIRM Panel Number(s)
East Bay CBRS 2/24/1997
12113C0527H 12113C0529H 12113C0531H 12113C0533G1
12113C0554H 12113C0558H
East Bay CBRS 11/16/1990
12113C0528H 12113C0529H 12113C0533G1
12113C0536H1
12113C0537H
12113C0554H 12113C0558H
Escambia Bay CBRS 11/16/1990 12113C0526H
12113C0527H
Gulf of Mexico CBRS 11/16/1990 12113C0588H
Pensacola Bay CBRS 11/16/1990
12113C0514G1
12113C0518H1
12113C0528H 12113C0529H 12113C0602H
12113C0606H
Pensacola Bay OPA 11/16/1991
12113C0519H 12113C0538H 12113C0606H 12113C0607H 12113C0608H
Santa Rosa Sound OPA 11/16/1991 12113C0607H 12113C0626H
Santa Rosa Sound CBRS 11/16/1990 12113C0588H 1 Panel Not Printed
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SECTION 4.0 – AREA STUDIED
4.1 Basin Description Table 5 contains a description of the characteristics of the HUC-8 sub-basins within which each community falls. The table includes the main flooding sources within each basin, a brief description of the basin, and its drainage area.
Table 5: Basin Characteristics
HUC-8 Sub-Basin Name
HUC-8 Sub-Basin
Number
Primary Flooding Source Description of Affected Area
Drainage Area (square miles)
Blackwater Watershed 03140104 Blackwater
River
The Blackwater River is approximately 68 miles in length with a drainage area of approximately 865 square miles.
865
Escambia Watershed 03140305 Escambia
River
Escambia Watershed drains from Alabama south ultimately discharging into Escambia Bay.
760
Lower Conecuh Watershed 03140304 Escambia
River
The Lower Conecuh watershed is predominantly within Alabama with only approximately 12 square miles in Florida.
1,014
Pensacola Bay Watershed 03140105
Pensacola Bay, Gulf of Mexico and Santa Rosa
Sound
The Pensacola Bay watershed includes numerous contributing creeks and streams.
544
Yellow Watershed 03140103 Yellow River
The Yellow River is a 92-mile long river of which 61 miles occur in Florida’s Okaloosa, Santa Rosa and Walton Counties. The Yellow River flows in a southwesterly direction into the Blackwater Bay.
1,374
4.2 Principal Flood Problems Table 6 contains a description of the principal flood problems that have been noted for Santa Rosa County by flooding source.
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Table 6: Principal Flood Problems
Flooding Source Description of Flood Problems
Blackwater River
Flooding in the Blackwater River Basin is caused by stream overbank flow and hurricane storm surges, and sometimes a combination of both. Riverine flooding occurs frequently and is prevalent throughout the reach of the river where the riverbanks are low and the floodplain is wide. The flat slopes and wide, heavily vegetated floodplains aggravate the flood problem by preventing the rapid drainage of floodwaters. At flood stage, the Blackwater River covers large areas, flooding forest land, farmland, fishing resorts, and other businesses built on the floodplain.
Coastal Areas The coastal areas of Santa Rosa County are subject to widespread flooding resulting from storm surges that accompany hurricanes and other severe storms from one or more of the following flooding sources: the Gulf of Mexico, East Bay, Escambia Bay, Pensacola Bay, Blackwater Bay, and Santa Rosa Sound. Present conclusions about recurrent coastal flood elevations rely heavily on historical evidence from the continuous tidal records identified in Table 5. Areas near the beach may be subject to wave action and high velocity surges that can cause erosion and property damage.
All Sources Some of the worst floods to occur in northwestern Florida were caused by high intensity rainfall during hurricanes. The time of concentration of runoff for large basin rivers in northwestern Florida may be several days; consequently, peak flows do not, as a rule, coincide with hurricane tides at the coast. The smaller streams, however, have a shorter period of concentration of runoff and flood flow occurring concurrently with storm surge is more likely. This greatly increases the likelihood of inundation of low-lying areas along the coast. Maximum rainfall ordinarily occurs in the eastern half of the storm system. As the storm passes inland its intensity decreases, but heavy rainfall continues. Total precipitation of 12 inches recorded at a single station during a hurricane is not uncommon, and in northwestern Florida, rainfall has been as high as 24 inches for the duration of the storm.
Table 7 contains information about historic flood elevations in the communities within Santa Rosa County.
Table 7: Historic Flooding Elevations (Not Applicable to this Flood Risk Project)
4.3 Non-Levee Flood Protection Measures Table 8 contains information about non-levee flood protection measures within Santa Rosa County such as dams, jetties, and or dikes. Levees are addressed in Section 4.4 of this FIS Report.
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Table 8: Non-Levee Flood Protection Measures
Flooding Source
Structure Name
Type of Measure Location
Description of Measure
Albert Gordon Pond N/A Dam Outfall of pond N/A
Bear Creek Bear Lake Dam Dam Outfall of Beak Lake N/A
N/A N/A Dam
Approximately 500 southeast of intersection with Steeplehead Rd and Alligator Creek
N/A
Jacobs Creek N/A Dam Approximately 240 feet north of Riverview Ct. N/A
Reader Creek N/A Dam Approximately 280 feet east of Par Lane N/A
Rocky Creek Braden Ball Dam #1 Dam At Abel Avenue N/A
4.4 Levees This section is not applicable to this Flood Risk Project.
Table 9: Levees (Not Applicable to this Flood Risk Project)
SECTION 5.0 – ENGINEERING METHODS For the flooding sources in the community, standard hydrologic and hydraulic study methods were used to determine the flood hazard data required for this study. Flood events of a magnitude that are expected to be equaled or exceeded at least once on the average during any 10-, 25-, 50-, 100-, or 500-year period (recurrence interval) have been selected as having special significance for floodplain management and for flood insurance rates. These events, commonly termed the 10-, 25-, 50-, 100-, and 500-year floods, have a 10-, 4-, 2-, 1-, and 0.2% annual chance, respectively, of being equaled or exceeded during any year. Although the recurrence interval represents the long-term, average period between floods of a specific magnitude, rare floods could occur at short intervals or even within the same year. The risk of experiencing a rare flood increases when periods greater than 1 year are considered. For example, the risk of having a flood that equals or exceeds the 100-year flood (1-percent chance of annual exceedance) during the term of a 30-year mortgage is approximately 26 percent (about 3 in 10); for any 90-year period, the risk increases to approximately 60 percent (6 in 10). The analyses reported herein reflect flooding potentials based on conditions existing in the community at the time of completion of this study. Maps and flood elevations will be amended periodically to reflect future changes.
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In addition to these flood events, the “1-percent-plus”, or “1%+”, annual chance flood elevation has been modeled and included on the flood profile for certain flooding sources in this FIS Report. While not used for regulatory or insurance purposes, this flood event has been calculated to help illustrate the variability range that exists between the regulatory 1% annual chance flood elevation and a 1% annual chance elevation that has taken into account an additional amount of uncertainty in the flood discharges (thus, the 1% “plus”). For flooding sources whose discharges were estimated using regression equations, the 1%+ flood elevations are derived by taking the 1% annual chance flood discharges and increasing the modeled discharges by a percentage equal to the average predictive error for the regression equation. For flooding sources with gage- or rainfall-runoff-based discharge estimates, the upper 84-percent confidence limit of the discharges is used to compute the 1%+ flood elevations.
5.1 Hydrologic Analyses Hydrologic analyses were carried out to establish the peak elevation-frequency relationships for floods of the selected recurrence intervals for each flooding source studied. Hydrologic analyses are typically performed at the watershed level. Depending on factors such as watershed size and shape, land use and urbanization, and natural or man-made storage, various models or methodologies may be applied. A summary of the hydrologic methods applied to develop the discharges used in the hydraulic analyses for each stream is provided in Table 13. Greater detail (including assumptions, analysis, and results) is available in the archived project documentation. A summary of the discharges is provided in Table 10. Frequency Discharge-Drainage Area Curves used to develop the hydrologic models may also be shown in Figure 7 for selected flooding sources. A summary of stillwater elevations developed for non-coastal flooding sources is provided in Table 11. (Coastal stillwater elevations are discussed in Section 5.3 and shown in Table 17.) Stream gage information is provided in Table 12.
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Table 10: Summary of Discharges
Peak Discharge (cfs)
Flooding Source Location Drainage
Area (Square Miles)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance Existing
1% Annual Chance Future
0.2% Annual Chance
Beale Creek
Approximately 0.6 miles south of Vinewood lane
3.7 680 * 1,208 1,483 * 2,267
At confluence with Unnamed Tributary to Beale Creek
1.2 353 * 650 808 * 1,267
Approximately 500 feet south of Dunridge Drive
0.5 208 * 396 499 * 800
Big Coldwater Creek
At confluence with Blackwater River 257.1 10,993 * 20,033 24,902 * 39,155
At Munson Highway 237.0 10,412 * 18,961 23,562 * 37,020
Approximately 0.65 miles northwest of Steel Bridge Road
221.2 9,945 * 18,098 22,484 * 35,304
Approximately 1.8 miles of confluence with East Fork and West Fork Big Coldwater Creek
210.0 9,577 * 17,399 21,601 * 33,872
Blackwater River
Approximately 1 mile northeast of U.S. Highway 90
743 35,900 * 69,900 89,900 * 152,900
At Deaton Bridge Road 300 19,777 * 40,897 53,552 * 93,589
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Table 10: Summary of Discharges
Peak Discharge (cfs)
Flooding Source Location Drainage
Area (Square Miles)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance Existing
1% Annual Chance Future
0.2% Annual Chance
At County Boundary 274 35,900 * 69,900 89,900 * 152,900
Clear Creek
At confluence with Blackwater River 24.2 2,146 * 3,743 4,570 * 6,914
At Pat Brown Road 23.4 2,097 * 3,657 4,464 * 6,752
At Munson Highway 22.5 2,041 * 3,558 4,342 * 6,565
At Blackwater Heridage State Trail 19.3 1,844 * 3,209 3,914 * 5,910
Just upstream of Langley St 16.0 1,600 * 2,764 3,362 * 5,045
Just upstream of Hunters Oak Trail 4.5 747 * 1,319 1,616 * 2,458
East Bay River
Approximately 0.5 mile upstream of the confluence with Panther Creek
83.0 5,069 * 8,563 10,385 * 15,576
East Fork Big Coldwater Creek
Approximately 0.5 mile north of Springhill Road
93.8 6,096 * 11,349 14,215 * 22,670
At confluence with Wolt Creek 88.6 6,039 * 11,358 14,281 * 22,952
Approximately 1,000 feet northeast of Horseshoe Loop Road
78.6 5,707 * 10,813 13,634 * 22,030
35
Table 10: Summary of Discharges
Peak Discharge (cfs)
Flooding Source Location Drainage
Area (Square Miles)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance Existing
1% Annual Chance Future
0.2% Annual Chance
Escambia River Just upstream of U.S. Route 90 4,084 83,665 * 163,110 209,605 * 356,680
At State Route 184 4,147 82,153 * 134,177 161,087 * 237,286
At State Route 4 3,817 76,322 * 121,929 145,039 * 208,946
Jacobs Creek
Approximately 900 feet north of confluence with Pace Mill Creek
1.1 306 * 539 660 * 1000
Approximately 100 feet north of Riverview Court
0.8 226 * 388 470 * 698
Approximately 250 feet west of Becky Lane
0.2 101 * 170 204 * 296
Juniper Creek
Approximately 0.5 mile southeast of Dupree Road
18.0 1,914 * 3,434 4,238 * 6,548
Approximately 2,000 feet south of County Mill Road
12.1 1,537 * 2,797 3,468 * 5,412
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Table 10: Summary of Discharges
Peak Discharge (cfs)
Flooding Source Location Drainage
Area (Square Miles)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance Existing
1% Annual Chance Future
0.2% Annual Chance
Manning Creek
Approximately 1,500 feet south of Highway 87
12.7 1,305 * 2,210 2,666 * 3,937
Approximately 0.5 mile northeast of Highway 87
11.7 1,241 * 2,099 2,532 * 3,736
At Van Jerigan Road 10.4 1,123 * 1,884 2,265 * 3,321
Pace Mill Creek Approximately 2,000 feet downstream of U.S. Route 90
6.2 1,838 * 3,540 4,091 * 5,881
Pond Creek
At Willard Norris Road 65.5 4,500 * 8,155 10,109 * 15,781
Approximately 400 feet west of Oser Road
54.4 3,919 * 7,049 8,712 * 13,519
Approximately 900 feet northeast of confluence with Three Hollow Creek
39.3 3,050 * 5,401 6,634 * 10,163
Approximately 450 feet east of Wendt Farm Road
18.0 1,776 * 3,102 3,788 * 5,732
Approximately 2,000 feet north of Forty Acre Pond
5.8 879 * 1,546 1,891 * 2,871
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Table 10: Summary of Discharges
Peak Discharge (cfs)
Flooding Source Location Drainage
Area (Square Miles)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance Existing
1% Annual Chance Future
0.2% Annual Chance
Reader Creek
Approximately 1,000 feet southwest of Martin Road
10.3 1,437 * 2,646 3,296 * 5,189
Approximately 100 feet northwest of Fairway Drive
6.8 1,069 * 1,946 2,414 * 3,763
Rocky Creek
Approximately 400 feet south of Pattock Place
1.4 292 * 478 568 * 812
Approximately 370 feet south of Abel Avenue
1.0 232 * 375 445 * 632
Approximately 150 feet south of Rowe Trail
0.6 146 * 228 266 * 366
Unnamed Tributary to Beale Creek
At Confluence with Beale Creek 2.2 457 * 798 973 * 1,465
Approximately 400 feet south of Twin Creek Circle
0.2 53 * 75 84 * 108
West Fork Big Coldwater Creek
Approximately 1,000 feet from confluence with East Fork Bigh Coldwater Creek
109.7 5,921 * 10,503 12,916 * 19,860
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Table 10: Summary of Discharges
Peak Discharge (cfs)
Flooding Source Location Drainage
Area (Square Miles)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance Existing
1% Annual Chance Future
0.2% Annual Chance
At confluence with Juniper Creek 62.2 4,129 * 7,333 9,020 * 13,866
Yellow River
At confluence with Blackwater Bay 1,344 33,600 * 65,550 84,240 * 143,350
Approximately 1.2 miles southeast of County Boundary
1,246 31,450 * 61,230 78,790 * 134,080
*Not calculated for this Flood Risk Project
Figure 7: Frequency Discharge-Drainage Area Curves (Not Applicable to this Flood Risk Project)
Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
B0020N At Ponding Area 139 * * * 10.9 11.2
B0060N At Ponding Area 67 * * * 19.5 19.6
B0080N At Ponding Area 160 * * * 24.1 24.3
B0100N At Ponding Area 71 * * * 29.9 30.0
39
Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
B0130N At Ponding Area 172 * * * 32.4 32.4
B0180N At Ponding Area 170 * * * 32.9 32.9
B0240N At Ponding Area 70 * * * 31.4 31.5
B0245N At Ponding Area 173 * * * 32.5 32.5
B1040N At Ponding Area 5 * * * 18.8 18.8
I0020N At Ponding Area 1 * * * 2.4 2.9
I0040N At Ponding Area 151 * * * 9.0 10.1
I0080N At Ponding Area 150 * * * 11.9 13.1
I0100N At Ponding Area 149 * * * 18.8 19.5
I0110N At Ponding Area 29 * * * 13.2 14.6
I0115N At Ponding Area 12 * * * 16.5 17.3
I0120N At Ponding Area 31 * * * 17.2 18.1
I0130N At Ponding Area 95 * * * 18.9 19.3
I0150N At Ponding Area 99 * * * 24.2 25.1
I0170N At Ponding Area 76 * * * 25.0 25.5
I0210N At Ponding Area 107 * * * 30.8 30.9
40
Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
I0230N At Ponding Area 83 * * * 32.1 32.1
I0250N At Ponding Area 82 * * * 33.0 33.1
I0270N At Ponding Area 84 * * * 33.3 33.4
I0290N At Ponding Area 128 * * * 33.3 33.4
I0330N At Ponding Area 50 * * * 35.9 35.9
I0340N At Ponding Area 54 * * * 38.5 38.6
I0342PN At Ponding Area 24 * * * 38.3 38.6
I0350N At Ponding Area 57 * * * 38.6 38.7
I0370N At Ponding Area 26 * * * 40.2 40.3
I0420N At Ponding Area 53 * * * 40.3 40.5
I0460N At Ponding Area 102 * * * 28.2 28.3
I0480N At Ponding Area 104 * * * 27.5 27.7
I0500N At Ponding Area 109 * * * 30.2 30.3
I0520N At Ponding Area 115 * * * 32.0 32.1
I0540N At Ponding Area 118 * * * 32.5 32.7
I0590N At Ponding Area 80 * * * 32.0 32.1
41
Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
I0610N At Ponding Area 119 * * * 32.5 32.6
I0640N At Ponding Area 75 * * * 27.8 28.0
I0660N At Ponding Area 168 * * * 29.8 29.9
I0670N At Ponding Area 108 * * * 30.8 30.9
I0700N At Ponding Area 120 * * * 31.7 31.7
I0740N At Ponding Area 78 * * * 32.7 32.8
I0760N At Ponding Area 85 * * * 33.4 33.5
I0780N At Ponding Area 87 * * * 33.5 33.5
I0800N At Ponding Area 129 * * * 33.5 33.6
I0820N At Ponding Area 46 * * * 32.5 32.6
I0840N At Ponding Area 21 * * * 33.4 33.4
I0870N At Ponding Area 88 * * * 33.4 33.5
I0875N At Ponding Area 165 * * * 36.0 36.0
I0940N At Ponding Area 123 * * * 32.4 32.4
I1030N At Ponding Area 72 * * * 28.1 28.2
I1050N At Ponding Area 98 * * * 28.2 28.4
42
Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
I1070N At Ponding Area 39 * * * 28.7 28.7
I3000N At Ponding Area 56 * * * 39.8 39.9
I3001N At Ponding Area 114 * * * 32.4 32.6
I3002N At Ponding Area 106 * * * 31.9 32.0
I3003N At Ponding Area 55 * * * 38.5 38.6
I3004N At Ponding Area 163 * * * 32.7 32.7
I3005N At Ponding Area 164 * * * 33.0 33.1
I3010N At Ponding Area 92 * * * 37.9 38.2
I3040N At Ponding Area 130 * * * 38.8 38.9
I3060N At Ponding Area 25 * * * 39.1 39.1
I3070N At Ponding Area 135 * * * 39.5 39.7
I3090N At Ponding Area 52 * * * 39.4 39.5
I3130N At Ponding Area 134 * * * 39.8 40.1
I3200N At Ponding Area 133 * * * 33.5 33.6
I4020N At Ponding Area 51 * * * 39.8 39.9
I4040N At Ponding Area 59 * * * 40.0 40.1
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Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
I4080N At Ponding Area 58 * * * 40.3 40.5
I4140N At Ponding Area 136 * * * 39.8 40.1
I5020N At Ponding Area 86 * * * 32.6 32.7
I5050N At Ponding Area 127 * * * 32.6 32.7
I8030N At Ponding Area 79 * * * 31.7 31.8
I9000N At Ponding Area 111 * * * 33.6 33.7
I9002N At Ponding Area 126 * * * 33.5 33.6
I9003N At Ponding Area 132 * * * 33.6 33.6
I9004N At Ponding Area 162 * * * 34.1 34.1
I9005N At Ponding Area 110 * * * 30.8 30.9
I9006N At Ponding Area 117 * * * 30.8 31.0
I9007N At Ponding Area 161 * * * 33.9 34.0
J0015N At Ponding Area 13 * * * 21.0 21.4
J0020N At Ponding Area 33 * * * 23.3 23.9
J0040N At Ponding Area 36 * * * 26.2 26.9
J0050N At Ponding Area 105 * * * 30.0 30.1
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Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
J0080N At Ponding Area 174 * * * 31.5 31.7
J0110N At Ponding Area 113 * * * 31.5 31.7
J0130N At Ponding Area 116 * * * 32.5 32.6
J0150N At Ponding Area 122 * * * 32.6 32.7
J0170N At Ponding Area 89 * * * 32.6 32.7
J0190N At Ponding Area 23 * * * 32.9 33.0
J0210N At Ponding Area 90 * * * 33.2 33.3
J0230N At Ponding Area 91 * * * 34.4 34.5
J0260N At Ponding Area 131 * * * 35.6 35.7
J0270N At Ponding Area 49 * * * 35.6 35.7
J0340N At Ponding Area 37 * * * 29.9 30.1
J0380N At Ponding Area 101 * * * 30.0 30.2
J0400N At Ponding Area 18 * * * 30.1 30.2
J0410N At Ponding Area 42 * * * 30.2 30.3
J0450N At Ponding Area 81 * * * 32.5 32.6
J0460N At Ponding Area 125 * * * 32.6 32.7
45
Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
J0470N At Ponding Area 22 * * * 32.8 32.9
J0490N At Ponding Area 48 * * * 33.2 33.3
J0570N At Ponding Area 44 * * * 32.0 32.3
J0580N At Ponding Area 45 * * * 31.9 32.1
J0590N At Ponding Area 156 * * * 32.4 32.5
J0600N At Ponding Area 155 * * * 31.5 31.7
J0630N At Ponding Area 19 * * * 32.7 32.8
J0660N At Ponding Area 20 * * * 33.0 33.1
J0700N At Ponding Area 41 * * * 30.0 30.1
J0750N At Ponding Area 43 * * * 31.5 31.7
J0760N At Ponding Area 121 * * * 32.5 32.7
J0765N At Ponding Area 152 * * * 33.3 33.5
J0790N At Ponding Area 47 * * * 34.4 34.5
J0800N At Ponding Area 153 * * * 34.5 34.6
J0810N At Ponding Area 154 * * * 34.6 34.7
J0850N At Ponding Area 124 * * * 33.3 33.5
46
Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
J0870N At Ponding Area 171 * * * 32.4 32.5
J5030N At Ponding Area 40 * * * 30.7 30.9
J5130PN At Ponding Area 35 * * * 30.8 30.9
J5220N At Ponding Area 158 * * * 31.5 31.7
J5230N At Ponding Area 157 * * * 31.9 32.0
J5330N At Ponding Area 63 * * * 31.5 31.6
J8000N At Ponding Area 9 * * * 30.4 30.5
J8001N At Ponding Area 15 * * * 24.2 24.3
J8002N At Ponding Area 137 * * * 32.4 32.4
K0030N At Ponding Area 93 * * * 23.7 23.9
K0050N At Ponding Area 68 * * * 23.8 24.1
K0060N At Ponding Area 166 * * * 27.0 27.0
K0070N At Ponding Area 32 * * * 28.9 29.1
K0090N At Ponding Area 97 * * * 29.6 29.8
K0110N At Ponding Area 77 * * * 29.7 29.9
K0170N At Ponding Area 167 * * * 28.9 29.1
47
Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
K0180N At Ponding Area 38 * * * 29.0 29.2
K0200N At Ponding Area 73 * * * 29.5 29.7
K0220N At Ponding Area 17 * * * 29.6 29.8
K1040N At Ponding Area 103 * * * 31.7 31.8
K2030N At Ponding Area 112 * * * 31.8 31.9
K3030N At Ponding Area 94 * * * 26.8 27.2
K3050N At Ponding Area 96 * * * 28.9 29.0
K3070N At Ponding Area 74 * * * 29.0 29.1
K3090N At Ponding Area 100 * * * 29.2 29.3
K4000N At Ponding Area 16 * * * 29.4 29.4
L0062PN At Ponding Area 6 * * * 20.2 20.3
L0064PN At Ponding Area 7 * * * 20.4 20.5
L2010PN At Ponding Area 2 * * * 17.2 17.4
L3000N At Ponding Area 27 * * * 20.5 20.6
M0010N At Ponding Area 142 * * * 7.7 8.1
M0030N At Ponding Area 61 * * * 12.2 12.6
48
Table 11: Summary of Non-Coastal Stillwater Elevations
Elevations (feet NAVD88)
Flooding Source Location 10% Annual
Chance 4% Annual
Chance 2% Annual
Chance 1% Annual
Chance 0.2% Annual
Chance
M0035N At Ponding Area 66 * * * 16.2 16.3
M0040PN At Ponding Area 11 * * * 17.4 17.8
M0050N At Ponding Area 28 * * * 26.2 26.5
M0070N At Ponding Area 14 * * * 28.3 28.6
M0090N At Ponding Area 30 * * * 30.5 30.6
M0100N At Ponding Area 69 * * * 30.7 30.8
M0110N At Ponding Area 159 * * * 31.8 31.8
M0130N At Ponding Area 4 * * * 12.3 12.6
M0135N At Ponding Area 169 * * * 14.1 14.5
M0140PN At Ponding Area 3 * * * 19.3 19.5
M1050PN At Ponding Area 8 * * * 28.3 28.4
M1052PN At Ponding Area 10 * * * 25.7 26.6
M2020N At Ponding Area 141 * * * 10.3 10.7
M2020PN At Ponding Area 140 * * * 11.1 11.2
M4000N At Ponding Area 34 * * * 31.0 31.0
*Not calculated for this Flood Risk Project
49
Table 12: Stream Gage Information used to Determine Discharges (Not Applicable to this Flood Risk Project)
5.2 Hydraulic Analyses Analyses of the hydraulic characteristics of flooding from the sources studied were carried out to provide estimates of the elevations of floods of the selected recurrence intervals. Base flood elevations on the FIRM represent the elevations shown on the Flood Profiles and in the Floodway Data tables in the FIS Report. Rounded whole-foot elevations may be shown on the FIRM in coastal areas, areas of ponding, and other areas with static base flood elevations. These whole-foot elevations may not exactly reflect the elevations derived from the hydraulic analyses. Flood elevations shown on the FIRM are primarily intended for flood insurance rating purposes. For construction and/or floodplain management purposes, users are cautioned to use the flood elevation data presented in this FIS Report in conjunction with the data shown on the FIRM. The hydraulic analyses for this FIS were based on unobstructed flow. The flood elevations shown on the profiles are thus considered valid only if hydraulic structures remain unobstructed, operate properly, and do not fail. For streams for which hydraulic analyses were based on cross sections, locations of selected cross sections are shown on the Flood Profiles (Exhibit 1). For stream segments for which a floodway was computed (Section 6.3), selected cross sections are also listed on Table 24, “Floodway Data.” A summary of the methods used in hydraulic analyses performed for this project is provided in Table 13. Roughness coefficients are provided in Table 14 Roughness coefficients are values representing the frictional resistance water experiences when passing overland or through a channel. They are used in the calculations to determine water surface elevations. Greater detail (including assumptions, analysis, and results) is available in the archived project documentation.
50
Table 13: Summary of Hydrologic and Hydraulic Analyses
Flooding Source
Study Limits Downstream Limit
Study Limits Upstream Limit
Hydrologic Model or
Method Used
Hydraulic Model or
Method Used
Date Analyses
Completed Flood Zone
on FIRM Special Considerations
Beale Creek At confluence Escambia River
Approximately 800 feet southwest of Curtis Road
2011 Regression Equations
HEC-RAS 3.1.3 2012 AE
Big Coldwater Creek
At confluence with Blackwater River
Approximately 0.65 miles northwest of Steel Bridge Road
2011 Regression Equations
HEC-RAS 4.1.0 2018 AE
Big Coldwater Creek
Approximately 0.65 miles northwest of Steel Bridge Road
At confluence with East Fork Big Coldwater Creek and West Fork Big Coldwater Creek
2011 Regression Equations
HEC-RAS 3.1.3 2012 AE
Blackwater River At Interstate 10
Approximately 620 feet downstream Deaton Bridge Road
2011 Regression Equations
HEC-2 V4.6.2
2012 AE w/ Floodway
Blackwater River
Approximately 620 feet downstream Deaton Bridge Road
At County Boundary
2011 Regression Equations
HEC-2 V4.6.2
2012 AE
Bray Mill Creek At confluence with Escambia River
At Town of Jay Boundary
Regression Equations
HEC-RAS 3.1.3 2012 A
51
Table 13: Summary of Hydrologic and Hydraulic Analyses
Flooding Source
Study Limits Downstream Limit
Study Limits Upstream Limit
Hydrologic Model or
Method Used
Hydraulic Model or
Method Used
Date Analyses
Completed Flood Zone
on FIRM Special Considerations
Clear Creek At confluence with Blackwater River
Just upstream of Blackwater Heritage State Trail
2011 Regression Equations
HEC-RAS 4.1.0 2018 AE
Clear Creek
Just upstream of Blackwater Heritage State Trail
Approximately 1,400 feet south of Forrest Hills Rd
2011 Regression Equations
HEC-RAS 3.1.3 2012 AE
East Bay River At confluence with East Bay
At County Boundary Bulletin 17A HEC-2 1984 AE w/
Floodway
East Fork Big Coldwater Creek
At confluence with Big Coldwater Creek and West Fork Big Coldwater Creek
Approximately 0.5 miles east of Gordon Land Rd.
2011 Regression Equations
HEC-RAS 3.1.3 2012 AE
Escambia River At US 10 Just upstream
Highway 4
Log Pearson Type III
Frequency Analysis
HEC-2 2005 AE w/ Floodway
Escambia River
Just upstream Highway 4
At Florida/Alabama state line
Log Pearson Type III
Frequency Analysis
HEC-2 2005 A
Holley By The Sea Entire Watershed Entire Watershed ICPR v3.1 ICPR v3.1 2016 AE
Holley By The Sea Entire Watershed Entire Watershed ICPR v3.1 ICPR v3.1 2016 A
52
Table 13: Summary of Hydrologic and Hydraulic Analyses
Flooding Source
Study Limits Downstream Limit
Study Limits Upstream Limit
Hydrologic Model or
Method Used
Hydraulic Model or
Method Used
Date Analyses
Completed Flood Zone
on FIRM Special Considerations
Jacobs Creek At confluence with Pace Mill Creek
At Becky Lane 2011
Regression Equations
HEC-RAS 3.1.3 2012 AE
Juniper Creek
At confluence with West Fork Big Coldwater Creek
Approximately 0.7 miles upstream County Mill Road
2011 Regression Equations
HEC-RAS 3.1.3 2012 AE
Juniper Creek
Approximately 0.7 miles upstream County Mill Road
Approximately 630 feet south of Letcher Block Road
2011 Regression Equations
HEC-RAS 3.1.3 2012 A
Long Branch At confluence with Pond Creek
At Long Branch Pond
2011 Regression Equations
HEC-RAS 3.1.3 2012 A
Malloy Branch
At confluence with West Fork Big Coldwater Creek
At Town of Jay Boundary
2011 Regression Equations
HEC-RAS 3.1.3 2012 A
Manning Creek
At confluence with West Fork Big Coldwater Creek
At Van Jernigan Road
2011 Regression Equations
HEC-RAS 3.1.3 2012 AE
Pace Mill Creek
At confluence with Escambia Bay
At Chumuckla Hwy
HEC-HMS 2.2.1
HEC-RAS 3.1.1 2005 AE w/
Floodway
Pond Creek At Willard Norris Road
Just upstream Fort Acre Pond
2011 Regression Equations
HEC-RAS 3.1.3 2012 AE
53
Table 13: Summary of Hydrologic and Hydraulic Analyses
Flooding Source
Study Limits Downstream Limit
Study Limits Upstream Limit
Hydrologic Model or
Method Used
Hydraulic Model or
Method Used
Date Analyses
Completed Flood Zone
on FIRM Special Considerations
Pond Creek At confluence with Blackwater River
At Willard Norris Road
HEC-HMS 2.2.1
HEC-RAS 3.1.1 2005 AE w/
Floodway
Reader Creek At confluence with Pond Creek At Fairway Drive
2011 Regression Equations
HEC-RAS 3.1.3 2012 AE
Rocky Creek At Confluence with Escambia River
At Rowe Trail 2011
Regression Equations
HEC-RAS 3.1.3 2012 AE
Unnamed Tributary to Beale Creek
At confluence with Beale Creek
Approximately 1,000 feet west of Cobblestone Rd
2011 Regression Equations
HEC-RAS 3.1.3 2012 AE
Unnamed Tributary to Bray Mill Creek
At confluence with Bray Mill Creek
Approximately 3,000 feet north of Highway 4
2011 Regression Equations
HEC-RAS 3.1.3 2012 A
Unnamed Tributary to Escambia River
At confluence with Escambia River
Approximately 300 feet north of Highway 4
2011 Regression Equations
HEC-RAS 4.1.0 2012 A
West Fork Big Coldwater Creek
At confluence with Big Coldwater Creek and East Fork Big Coldwater Creek
Just upstream confluence with Juniper Creek
2011 Regression Equations
HEC-RAS 3.1.3 2012 AE
West Fork Big Coldwater Creek
Just upstream confluence with Juniper Creek
At confluence with Malloy Branch
2011 Regression Equations
HEC-RAS 3.1.3 2012 A
54
Table 13: Summary of Hydrologic and Hydraulic Analyses
Flooding Source
Study Limits Downstream Limit
Study Limits Upstream Limit
Hydrologic Model or
Method Used
Hydraulic Model or
Method Used
Date Analyses
Completed Flood Zone
on FIRM Special Considerations
Yellow River At confluence with Blackwater Bay
County Boundary 2010
Regression Equations
HEC-2 V4.6.2
2012 AE w/ Floodway
55
Table 14: Roughness Coefficients
Flooding Source Channel “n” Overbank “n”
Beale Creek 0.020 – 0.096 0.043 – 0.129
Big Coldwater Creek 0.040 – 0.083 0.040 – 0.125
Blackwater River 0.070 – 0.044 0.030 – 0.200
Clear Creek 0.065 – 0.096 0.045 – 0.129
East Bay River 0.035 – 0.045 0.150 – 0.180
East Fork Big Coldwater Creek 0.040 – 0.083 0.040 – 0.125
Escambia River 0.035 – 0.045 0.150 – 0.180
Jacobs Creek 0.065 – 0.091 0.043 – 0.124
Juniper Creek 0.040 – 0.083 0.040 – 0.125
Long Branch 0.065 – 0.091 0.043 – 0.124
Manning Creek 0.040 – 0.083 0.040 – 0.125
Pace Mill Creek 0.065 – 0.091 0.043 – 0.124
Pond Creek 0.035 – 0.050 0.043 – 0.129
Reader Creek 0.035 – 0.050 0.043 – 0.129
Rocky Creek 0.020 – 0.091 0.043 – 0.124
Unnamed Tributary to Beale Creek 0.020 – 0.091 0.043 – 0.129
West Fork Big Coldwater Creek 0.040 – 0.083 0.040 – 0.125
Yellow River 0.070 – 0.044 0.030 – 0.200
5.3 Coastal Analyses For the areas of Santa Rosa County that are impacted by coastal flooding processes, coastal flood hazard analyses were performed to provide estimates of coastal BFEs. Coastal BFEs reflect the increase in water levels during a flood event due to extreme tides and storm surge as well as overland wave effects. The following subsections provide summaries of how each coastal process was considered for this FIS Report. Greater detail (including assumptions, analysis, and results) is available in the archived project documentation. Table 15 summarizes the methods and/or models used for the coastal analyses. Refer to Section 2.5.1 for descriptions of the terms used in this section.
56
Table 15: Summary of Coastal Analyses
Flooding Source
Study Limits From
Study Limits To
Hazard Evaluated
Model or Method Used
Date Analysis
was Completed
Blackwater Bay
Entire Shoreline
Entire Shoreline
Storm Surge, Wave
Runup, Wave Height
Analysis, Erosion
ADCIRC, CHAMP,
TAW, CSHORE, Runup 2.0
2015
East Bay Entire Shoreline
Entire Shoreline
Storm Surge, Wave
Runup, Wave Height
Analysis, Erosion
ADCIRC, CHAMP,
TAW, CSHORE, Runup 2.0
2015
Escambia Bay Entire Shoreline
Entire Shoreline
Storm Surge, Wave
Runup, Wave Height
Analysis, Erosion
ADCIRC, CHAMP,
TAW, CSHORE, Runup 2.0
2015
Gulf of Mexico Entire Shoreline
Entire Shoreline
Storm Surge, Wave
Runup, Wave Height
Analysis, Erosion
ADCIRC, CHAMP,
TAW, CSHORE, Runup 2.0
2015
Pensacola Bay Entire Shoreline
Entire Shoreline
Storm Surge, Wave
Runup, Wave Height
Analysis, Erosion
ADCIRC, CHAMP,
TAW, CSHORE, Runup 2.0
2015
Santa Rosa Sound
Entire Shoreline
Entire Shoreline
Storm Surge, Wave
Runup, Wave Height
Analysis, Erosion
ADCIRC, CHAMP,
TAW, CSHORE, Runup 2.0
2015
5.3.1 Total Stillwater Elevations The total stillwater elevations (stillwater including storm surge plus wave setup) for the 1% annual chance flood were determined for areas subject to coastal flooding. The models and methods that were used to determine storm surge and wave setup are listed in Table 15. The stillwater elevation that was used for each transect in coastal analyses is shown in Table 17, “Coastal Transect
57
Parameters.” Figure 8 shows the total stillwater elevations for the 1% annual chance flood that was determined for this coastal analysis.
Figure 8: 1% Annual Chance Total Stillwater Elevations for Coastal Areas
Astronomical Tide Astronomical tidal statistics were generated directly from local tidal constituents by sampling the predicted tide at random times throughout the tidal epoch. Storm Surge Statistics Storm surge is modeled based on characteristics of actual storms responsible for significant coastal flooding. The characteristics of these storms are typically determined by statistical study of the regional historical record of storms or by statistical study of tidal gages.
Table 16: Tide Gage Analysis Specifics (Not Applicable to this Flood Risk Project)
58
Combined Riverine and Tidal Effects This section is not applicable to this Flood Risk Project. Wave Setup Analysis Wave setup was computed during the storm surge modeling through the methods and models listed in Table 15 and included in the frequency analysis for the determination of the total stillwater elevations. The oscillating component of wave setup, dynamic wave setup, was calculated for areas subject to wave runup hazards.
5.3.2 Waves The region wide storm surge modeling system includes the Advanced Circulation Model for Oceanic, Coastal and Estuarine Waters (ADCIRC) for simulation of 2-dimensional hydrodynamics. ADCIRC was “loosely” coupled to the unstructured numerical wave model Simulating Waves Nearshore (unSWAN) to calculate the contribution of waves to total storm surge (FEMA, 2010). The resulting model system is typically referred to as SWAN+ADCIRC. A seamless modeling grid was developed to support the storm surge modeling efforts. The modeling system validation consisted of a comprehensive tidal calibration followed by a validation using carefully reconstructed wind and pressure fields for five major flood events affecting the region: Hurricane Opal, Hurricane Georges, Hurricane Ivan, Hurricane Dennis and Hurricane Katrina
Model skill was assessed by quantitative comparison of model output to wind, wave, and high water mark observations. The model was then used to re-create 295 synthetic hurricanes to create a synthetic water elevation record from which the 10-, 2-, 1-, and 0.2- percent annual chance of exceedance elevations were determined.
Wave setup results in an increased water level at the shoreline due to the breaking of waves and transfer of momentum to the water column during hurricanes and severe storms. For the Florida Panhandle and Alabama surge study, wave setup was determined directly from the coupled wave and storm surge model. The total stillwater elevation with wave setup was then used for the erosion and overland wave modeling.
5.3.3 Coastal Erosion A single storm episode can cause extensive erosion in coastal areas. Storm-induced erosion was evaluated to determine the modification to existing topography that is expected to be associated with flooding events. Erosion was evaluated using the methods listed in Table 15. The post-event eroded profile was used for the subsequent transect-based onshore wave hazard analyses.
5.3.4 Wave Hazard Analyses Overland wave hazards were evaluated to determine the combined effects of ground elevation, vegetation, and physical features on overland wave propagation and wave runup. These analyses were performed at representative transects along all shorelines for which waves were expected to be present during the floods of the selected recurrence intervals. The results of these analyses were used to determine elevations for the 1% annual chance flood.
59
Transect locations were chosen with consideration given to the physical land characteristics as well as development type and density so that they would closely represent conditions in their locality. Additional consideration was given to changes in the total stillwater elevation. Transects were spaced close together in areas of complex topography and dense development or where total stillwater elevations varied. In areas having more uniform characteristics, transects were spaced at larger intervals. Transects shown in Figure 9, “Transect Location Map,” are also depicted on the FIRM. Table 17 provides the location, stillwater elevations, and starting wave conditions for each transect evaluated for overland wave hazards. In this table, “starting” indicates the parameter value at the beginning of the transect. Wave Height Analysis Wave height analyses were performed to determine wave heights and corresponding wave crest elevations for the areas inundated by coastal flooding and subject to overland wave propagation hazards. Refer to Figure 6 for a schematic of a coastal transect evaluated for overland wave propagation hazards. Wave heights and wave crest elevations were modeled using the methods and models listed in Table 15, “Summary of Coastal Analyses”. Wave Runup Analysis Wave runup analyses were performed to determine the height and extent of runup beyond the limit of stillwater inundation for the 1% annual chance flood. Wave runup is defined as the maximum vertical extent of wave uprush on a beach or structure. FEMA’s 2007 Guidelines and Specifications require the 2-percent wave runup level be computed for the coastal feature being evaluated (cliff, coastal bluff, dune, or structure) (FEMA, February 2007). The 2-percent runup level is the highest 2 percent of wave runup affecting the shoreline during the 1-percent-annual- chance flood event. Each transect defined within the study area was evaluated for the applicability of wave runup, and if necessary, the appropriate runup methodology was selected and applied to each transect. Runup elevations were then compared to WHAFIS results to determine the dominant process affecting BFEs and associated flood hazard levels. Based on wave runup rates, wave overtopping was computed following the FEMA 2007 Guidelines and Specifications. Wave runup elevations were modeled using the methods and models listed in Table 15.
60
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Gulf of Mexico 1 20.6 15.8 5.1 * 8.4 9.2 12.5
4.1-5.1 5.7-8.4 7.4-9.2 12.0-12.5
Gulf of Mexico 2 20.1 16.6 5.2 * 8.4 9.8 12.4
4.3-5.2 6.1-8.4 7.6-9.8 12.3-12.7
Escambia Bay 3 4.2 4.0 5.4 * 9.2 11.0 14.6
4.2-5.6 7.7-9.5 9.2-11. 12.1-15.3
Escambia Bay 4 4.5 4.2 5.6 * 9.6 11.7 15.6
5.0-5.6 8.9-9.8 11.2-11 15.6-15.7
61
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Escambia Bay 5 4.6 4.2 5.5 * 9.6 11.5 15.5
5.2-5.5 9.2-9.6 11.2-11 15.1-15.5
Escambia Bay 6 4.4 4.3 5.3 * 9.2 11.0 14.9
4.8-5.3 8.3-9.2 10.5-11 14.4-14.9
Escambia Bay 7 4.5 4.0 5.2 * 8.8 10.5 14.3
4.6-5.2 7.7-8.9 9.2-10. 14.0-14.6
Escambia Bay 8 4.8 4.2 4.9 * 8.3 9.9 13.5
4.2-5.1 7.5-8.7 9.4-10. 13.5-14.4
62
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Escambia Bay 9 4.2 3.9 4.8 * 8.1 9.7 13.3
4.2-5.1 5.0-8.2 9.1-10. 13.2-14.3
Escambia Bay 10 4.1 4.1 4.7 * 7.7 9.2 12.7
3.9-4.7 3.2-7.7 8.3-9.2 12.6-13.0
Escambia Bay 11 4.2 4.5 4.6 * 7.4 8.7 11.9
4.4-4.6 5.6-7.4 7.6-8.7 10.5-11.9
Escambia Bay 12 4.0 4.3 4.3 * 7.0 7.9 10.7
3.3-4.4 5.5-7.0 6.5-7.9 9.6-10.7
63
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
East Bay 13 3.8 4.1 4.3 * 6.8 7.7 9.9
3.3-4.5 5.4-6.9 6.4-7.9 9.5-10.3
East Bay 14 4.1 4.1 4.6 * 7.5 8.7 11.5
3.9-4.6 5.3-7.5 8.1-8.7 11.2-11.5
Blackwater Bay 15 4.0 3.9 4.7 * 7.7 8.8 11.9
3.4-4.7 6.3-7.8 8.1-8.8 11.1-11.9
Blackwater Bay 16 3.8 3.9 4.9 * 8.0 9.3 12.4
4.9-4.9 7.0-8.0 8.3-9.3 11.7-12.4
64
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Blackwater Bay 17 3.7 3.7 4.9 * 8.0 9.4 12.6
4.5-4.9 7.2-8.0 8.6-9.6 11.9-12.6
Blackwater Bay 18 3.0 2.9 5.1 * 8.6 10.1 13.5
4.6-5.2 7.1-8.6 9.0-10. 12.7-13.5
Blackwater Bay 19 3.1 2.7 5.0 * 8.5 10.0 13.6
3.4-5.0 7.2-8.5 9.0-10. 12.9-13.6
Blackwater Bay 20 3.3 3.5 4.9 * 8.1 9.5 12.7
3.6-4.9 6.5-8.1 7.9-9.6 11.7-13.0
65
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Blackwater Bay 21 3.2 3.6 4.8 * 8.0 9.3 12.5
3.4-4.8 6.0-8.0 7.3-9.5 10.1-12.8
Blackwater Bay 22 3.1 3.7 4.8 * 7.9 9.2 12.3
3.8-4.8 6.6-7.9 8.5-9.3 11.9-12.6
Blackwater Bay 23 3.1 3.7 4.7 * 7.7 9.0 12.0
4.1-4.7 6.4-7.7 8.1-9.0 11.2-12.1
East Bay 24 3.9 4.0 4.6 * 7.5 8.8 11.8
4.2-4.6 6.4-7.5 7.3-8.8 11.4-11.8
66
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
East Bay 25 3.7 3.9 4.5 * 7.4 8.7 11.7
4.4-4.5 7.1-7.4 7.8-8.7 11.5-11.7
East Bay 26 2.7 2.9 4.5 * 7.4 8.8 12.0
4.5-4.5 7.0-7.4 7.6-8.8 11.8-12.0
East Bay 27 2.6 2.6 4.5 * 7.4 8.8 12.0
4.3-4.5 6.6-7.4 7.3-8.8 12.0-12.3
East Bay 28 3.2 3.8 4.4 * 7.3 8.6 11.7
3.9-4.5 7.1-7.4 7.7-8.8 11.4-12.2
67
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
East Bay 29 3.1 3.9 4.4 * 7.3 8.2 11.4
4.4-4.4 7.3-7.3 8.0-8.4 11.1-11.6
East Bay 30 3.1 3.7 4.4 * 7.2 8.0 11.1
4.4-4.4 7.2-7.2 7.4-8.0 10.8-11.1
East Bay 31 2.9 3.7 4.3 * 7.0 7.9 10.8
4.3-4.3 6.9-7.0 7.6-8.0 10.8-10.8
East Bay 32 2.9 3.5 4.3 * 7.0 7.7 10.6
4.3-4.3 6.8-7.0 7.4-7.8 10.4-10.6
68
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
East Bay 33 2.9 3.6 4.2 * 6.9 7.7 10.3
4.2-4.2 6.9-6.9 6.6-7.7 10.3-10.3
East Bay 34 2.6 3.6 4.2 * 6.7 7.7 10.0
4.2-4.2 6.7-6.7 6.8-7.7 10.0-10.0
East Bay 35 2.5 3.6 4.1 * 6.6 7.6 9.7
4.1-4.1 5.3-6.6 6.7-7.6 9.7-9.7
Pensacola Bay 36 2.7 3.7 4.1 * 6.4 7.3 9.5
4.1-4.1 6.1-6.4 6.5-7.3 9.0-9.5
69
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Pensacola Bay 37 3.5 4.0 4.1 * 6.5 7.3 9.2
4.1-4.1 5.6-6.5 6.5-7.3 8.8-9.2
Pensacola Bay 38 3.7 4.2 4.1 * 6.5 7.4 9.3
4.1-4.1 6.5-6.6 7.1-7.4 9.3-9.3
Pensacola Bay 39 4.4 3.9 4.1 * 6.5 7.4 9.3
4.1-4.1 6.5-6.5 7.4-7.4 9.3-9.3
Pensacola Bay 40 4.9 4.0 4.2 * 6.5 7.4 9.3
4.1-4.2 6.5-6.5 7.4-7.4 9.3-9.4
70
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Pensacola Bay 41 3.7 4.4 4.3 * 6.9 7.9 10.6
4.2-4.3 6.7-6.9 7.5-7.9 10.6-10.6
Pensacola Bay 42 5.0 4.0 4.4 * 7.0 8.1 10.9
4.4-4.4 7.0-7.1 7.8-8.1 10.9-10.9
Pensacola Bay 43 5.1 3.7 4.4 * 7.1 8.3 11.7
4.3-4.4 6.9-7.1 7.8-8.3 11.7-11.7
Santa Rosa Sound 44 5.0 3.8 4.2 * 6.9 8.2 12.0
4.2-4.2 5.6-6.9 7.6-8.2 11.1-12.0
71
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Santa Rosa Sound 45 5.5 4.1 4.2 * 6.9 8.2 12.5
4.1-4.2 6.5-6.9 7.4-8.2 10.6-12.5
Santa Rosa Sound 46 5.6 4.2 4.1 * 6.8 8.1 12.9
4.1-4.1 6.7-6.8 6.4-8.1 12.9-12.9
Santa Rosa Sound 47 5.1 4.0 4.1 * 6.7 8.1 13.2
4.1-4.1 5.1-6.7 6.1-8.1 13.2-13.5
Santa Rosa Sound 48 5.0 4.0 4.1 * 6.5 8.0 13.3
4.1-4.1 5.1-6.5 6.5-8.0 13.3-13.8
72
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Santa Rosa Sound 49 4.7 3.7 4.1 * 6.8 8.1 13.1
4.1-4.1 5.2-6.8 6.5-8.1 13.1-13.6
Santa Rosa Sound 50 4.3 3.4 4.1 * 6.8 8.1 13.1
4.1-4.2 6.2-6.8 6.7-8.1 12.6-13.2
Santa Rosa Sound 51 4.6 3.6 4.2 * 6.9 7.8 13.0
4.2-4.2 6.8-6.9 6.4-7.8 13.0-13.0
Santa Rosa Sound 52 4.3 3.3 4.2 * 6.9 8.3 12.9
4.2-4.2 5.4-6.9 6.7-8.3 12.9-13.0
73
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Santa Rosa Sound 53 4.1 3.0 4.3 * 7.0 8.4 12.9
4.2-4.3 5.7-7.0 7.8-8.4 12.9-13.4
Santa Rosa Sound 55 3.9 2.9 4.3 * 7.1 8.4 12.9
4.3-4.3 7.1-7.2 8.2-8.4 12.9-13.1
Santa Rosa Sound 56 3.6 3.1 4.3 * 7.2 8.6 13.1
4.3-4.3 7.1-7.2 8.2-8.6 12.8-13.1
Santa Rosa Sound 57 3.9 2.8 4.4 * 7.3 8.7 13.2
4.1-4.4 6.8-7.3 8.4-8.7 13.0-13.2
74
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Santa Rosa Sound 58 3.1 3.0 4.4 * 7.3 8.7 13.2
4.2-4.4 7.0-7.3 8.1-8.7 13.0-13.2
Santa Rosa Sound 59 3.7 3.0 4.4 * 7.4 8.7 13.3
4.4-4.4 7.3-7.4 8.1-8.7 13.0-13.4
Santa Rosa Sound 60 3.7 3.0 4.4 * 7.4 9.0 13.4
4.4-4.4 7.4-7.5 8.6-9.0 13.2-13.4
Santa Rosa Sound 61 4.1 3.0 4.4 * 7.5 8.9 13.3
4.3-4.4 7.3-7.5 8.7-9.1 13.1-13.3
75
Table 17: Coastal Transect Parameters
Flood Source Coastal
Transect
Starting Wave Conditions for the 1% Annual Chance
Starting Stillwater Elevations (ft NAVD88) Range of Stillwater Elevations
(ft NAVD88)
Significant Wave Height
Hs (ft)
Peak Wave Period Tp (sec)
10% Annual Chance
4% Annual Chance
2% Annual Chance
1% Annual Chance
0.2% Annual Chance
Santa Rosa Sound 62 4.0 3.3 4.4 * 7.5 9.1 13.4
4.4-4.4 7.3-7.5 8.7-9.1 13.2-13.4
Santa Rosa Sound 63 3.8 3.1 4.5 * 7.6 9.1 13.3
4.3-4.5 7.6-7.6 9.1-9.1 13.3-13.3
Santa Rosa Sound 64 7.5 3.5 4.5 * 7.6 9.1 13.2
4.4-4.5 7.2-7.6 8.9-9.1 12.8-13.2
* Not calculated for this Flood Risk Project
NATIONAL FLOOD INSURANCE PROGRAMTRANSECT LOCATION MAP
FEMAHTTP://MSC.FEMA.GOV
THE INFORMATION DEPICTED ON THIS MAP AND SUPPORTINGDOCUMENTATION ARE ALSO AVAILABLE IN DIGITAL FORMAT AT
Map Projection:
SEE FLOOD INSURANCE STUDY FOR ADDITIONAL INFORMATION
¥¥10
£¤90
£¤98
¬«87
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Pond
Creek
East Bay
Escambia River
Santa Rosa Sound
Yellow River
Blackwater River
Moore Creek
Clear Creek
Escambia Bay
Sweet
water
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Juniper Creek
Pensacola Bay
Blackw
ater B
ay
Gulf Of Mexico
Mann
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West F
ork Bi
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Big Coldwater Creek
Ates Creek
Wolfe
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Alliga
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reek
Boiling CreekCobb Branch
Mcdavid Creek
East Bay River
White River
Danle
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Panther Creek
Weaver Creek
Pace Mill Creek
Wolf Creek
Pittman Creek
Bear CreekBig
Junip
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Crooked Creek
Buffalo
Mill Cree
kThomas
Creek
Weaver River
Dean Creek
Sevenmile Creek
Dead
River
Simpson River
Mulatto Bayou
Santa Rosa Sound
SANTA ROSA COUNTY120274
CITY OF MILTON120276
CITY OF GULF BREEZE120275
ESCAMBIA COUNTY(AREA NOT INCLUDED)
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1 in = 3 miles
0 1.5 3 4.5 60.75Miles
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,61, 62, 63, 64
and Incorporated AreasSANTA ROSA COUNTY, FLORIDASanta Rosa Transects: Florida State Plane North FIPS Zone 0903;
North American Datum 1983 HARN; GRS 1980 Spheroid
COUNTY LOCATOR
Figure 9: Transect Location Map
76
77
5.4 Alluvial Fan Analyses This section is not applicable to this Flood Risk Project
Table 18: Summary of Alluvial Fan Analyses (Not Applicable to this Flood Risk Project)
Table 19: Results of Alluvial Fan Analyses (Not Applicable to this Flood Risk Project)
SECTION 6.0 – MAPPING METHODS
6.1 Vertical and Horizontal Control All FIS Reports and FIRMs are referenced to a specific vertical datum. The vertical datum provides a starting point against which flood, ground, and structure elevations can be referenced and compared. Until recently, the standard vertical datum used for newly created or revised FIS Reports and FIRMs was the National Geodetic Vertical Datum of 1929 (NGVD29). With the completion of the North American Vertical Datum of 1988 (NAVD88), many FIS Reports and FIRMs are now prepared using NAVD88 as the referenced vertical datum. Flood elevations shown in this FIS Report and on the FIRMs are referenced to NAVD88. These flood elevations must be compared to structure and ground elevations referenced to the same vertical datum. For information regarding conversion between NGVD29 and NAVD88 or other datum conversion, visit the National Geodetic Survey website at www.ngs.noaa.gov, or contact the National Geodetic Survey (NGS) at the following address:
NGS Information Services NOAA, N/NGS12
National Geodetic Survey SSMC-3, #9202
1315 East-West Highway Silver Spring, Maryland 20910-3282
(301) 713-3242 Temporary vertical monuments are often established during the preparation of a flood hazard analysis for the purpose of establishing local vertical control. Although these monuments are not shown on the FIRM, they may be found in the archived project documentation associated with the FIS Report and the FIRMs for this community. Interested individuals may contact FEMA to access these data.
78
To obtain current elevation, description, and/or location information for benchmarks in the area, please contact the Information Services Branch of the NGS at (301) 713-3242, or visit their website at www.ngs.noaa.gov.
Table 20: Countywide Vertical Datum Conversion (Not Applicable to this Flood Risk Project)
Calculations for the vertical offsets for Escambia River basis are depicted in Table 21.
Table 21: Stream-Based Vertical Datum Conversion
Flooding Source Average Vertical Datum Conversion Factor (feet)
Escambia River -0.03
6.2 Base Map The FIRMs and FIS Report for this project have been produced in a digital format. The flood hazard information was converted to a Geographic Information System (GIS) format that meets FEMA’s FIRM database specifications and geographic information standards. This information is provided in a digital format so that it can be incorporated into a local GIS and be accessed more easily by the community. The FIRM Database includes most of the tabular information contained in the FIS Report in such a way that the data can be associated with pertinent spatial features. For example, the information contained in the Floodway Data table and Flood Profiles can be linked to the cross sections that are shown on the FIRMs. Additional information about the FIRM Database and its contents can be found in FEMA’s Guidelines and Standards for Flood Risk Analysis and Mapping, www.fema.gov/guidelines-and-standards-flood-risk-analysis-and-mapping. Base map information shown on the FIRM was derived from the sources described in Table 22.
Table 22: Base Map Sources
Data Type Data Provider Data Date Data Scale Data Description
Hydrological line and Polygon features
Santa Rosa County GIS Department
02/09/2012 N/A Hydrography
FDOT Imagery Florida Department of Transportation
09/17/2013 N/A Aerial Imagery
PLSS Santa Rosa County GIS Department
11/08/2011 N/A Public Land Survey System Boundaries
Transportation Features
Santa Rosa County GIS Department
11/08/2011 N/A Road Centerline Data
79
Table 22: Base Map Sources
Data Type Data Provider Data Date Data Scale Data Description
Coastal Barrier Resource System (CBRS) Boundaries
US Fish and Wildlife Service 04/24/2013 N/A CBRS Boundary Data
6.3 Floodplain and Floodway Delineation The FIRM shows tints, screens, and symbols to indicate floodplains and floodways as well as the locations of selected cross sections used in the hydraulic analyses and floodway computations. For riverine flooding sources, the mapped floodplain boundaries shown on the FIRM have been delineated using the flood elevations determined at each cross section; between cross sections, the boundaries were interpolated using the topographic elevation data described in Table 23. For each coastal flooding source studied as part of this FIS Report, the mapped floodplain boundaries on the FIRM have been delineated using the flood and wave elevations determined at each transect; between transects, boundaries were delineated using land use and land cover data, the topographic elevation data described in Table 23, and knowledge of coastal flood processes. In ponding areas, flood elevations were determined at each junction of the model; between junctions, boundaries were interpolated using the topographic elevation data described in Table 23. In cases where the 1% and 0.2% annual chance floodplain boundaries are close together, only the 1% annual chance floodplain boundary has been shown. Small areas within the floodplain boundaries may lie above the flood elevations but cannot be shown due to limitations of the map scale and/or lack of detailed topographic data. The floodway widths presented in this FIS Report and on the FIRM were computed for certain stream segments on the basis of equal conveyance reduction from each side of the floodplain. Floodway widths were computed at cross sections. Between cross sections, the floodway boundaries were interpolated. Table 2 indicates the flooding sources for which floodways have been determined. The results of the floodway computations for those flooding sources have been tabulated for selected cross sections and are shown in Table 24, “Floodway Data.”
Table 23: Summary of Topographic Elevation Data used in Mapping
Source for Topographic Elevation Data
Community Flooding Source Description Scale
Contour Interval RMSEz
Accuracyz Citation
Santa Rosa County (all communities)
All within HUC basins
03140103 03140104 03140105 03140304 03140305
Light Detection and Ranging data (LiDAR)
1:1200 N/A N/A N/A NWFWMD
80
BFEs shown at cross sections on the FIRM represent the 1% annual chance water surface elevations shown on the Flood Profiles and in the Floodway Data tables in the FIS Report. Rounded whole-foot elevations may be shown on the FIRM in coastal areas, areas of ponding, and other areas with static base flood elevations.
81
Table 24: Floodway Data
LOCATION FLOODWAY 1% ANNUAL CHANCE FLOOD WATER SURFACE
ELEVATION (FEET NAVD88)
CROSS SECTION DISTANCE1 WIDTH
(FEET)
SECTION AREA
(SQ. FEET)
MEAN VELOCITY
(FEET/SEC) REGULATORY WITHOUT
FLOODWAY WITH
FLOODWAY INCREASE
A 9,342 1,380 13,046 6.9 10.1 2.82 2.8 0.0 B 10,605 2,540 20,654 4.4 10.1 5.42 5.4 0.0 C 11,960 3,491 25,814 3.5 10.1 7.62 7.8 0.2 D 14,578 2,885 32,140 2.8 10.9 10.9 11.1 0.2 E 16,459 3,242 40,638 2.2 12.0 12.0 12.2 0.2 F 17,731 2,840 37,961 2.4 13.1 13.1 13.3 0.2 G 21,056 2,640 40,268 2.2 14.4 14.4 14.5 0.1 H 23,348 3,472 55,609 1.6 15.1 15.1 15.3 0.2 I 26,807 4,846 56,390 1.6 16.1 16.1 16.4 0.3 J 31,849 5,073 76,450 1.2 16.6 16.6 17.0 0.4 K 36,996 4,605 66,788 1.3 17.9 17.9 18.5 0.6 L 37,937 4,924 62,653 1.4 18.1 18.1 18.7 0.6 M 45,014 4,615 75,934 1.2 19.0 19.0 19.6 0.6 N 49,166 4,115 55,420 1.6 19.6 19.6 20.2 0.6 O 51,919 4,230 69,460 1.2 20.5 20.5 21.1 0.6 P 55,733 3,791 46,881 1.8 21.8 21.8 22.4 0.6 Q 62,743 3,024 43,975 1.9 24.0 24.0 24.7 0.7 R 68,973 2,413 35,370 2.4 26.3 26.3 27.0 0.7 S 72,997 3,364 56,885 1.5 28.8 28.8 29.5 0.7 T 76,544 2,582 47,582 1.8 30.1 30.1 30.8 0.7 U 80,226 2,825 51,100 1.6 32.3 32.3 33.1 0.8 V 84,523 2,818 47,472 1.1 33.3 33.3 34.1 0.8 W 90,387 3,953 73,029 0.7 34.4 34.4 35.3 0.9 X 93,456 4,366 64,261 0.8 34.8 34.8 35.7 0.9 Y 97,816 2,280 40,401 1.3 36.5 36.5 37.4 0.9 Z 99,764 1,497 27,873 1.9 37.6 37.6 38.5 0.9 AA – AU3 1Feet above mouth at Blackwater Bay 2Elevation computed without consideration of Blackwater Bay storm surge effects 3Floodway data not computed, see Table 25 for elevations
TABLE 24
FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SANTA ROSA COUNTY, FL
FLOODING SOURCE: BLACKWATER RIVER AND INCORPORATED AREAS
82
LOCATION FLOODWAY 1% ANNUAL CHANCE FLOOD WATER SURFACE
ELEVATION (FEET NAVD88)
CROSS SECTION DISTANCE1 WIDTH
(FEET)
SECTION AREA
(SQ. FEET)
MEAN VELOCITY
(FEET/SEC) REGULATORY WITHOUT
FLOODWAY WITH
FLOODWAY INCREASE
A 700 200 1,912 5.4 8.9 2.12 3.1 1.0 B 2,900 200 1,862 5.6 8.9 2.52 5.1 0.6 C 5,050 260 3,121 3.3 8.9 5.82 6.3 0.5 D 5,192 260 3,130 3.3 8.9 5.82 6.3 0.5 E 12,392 1,072 7,834 1.3 8.9 7.02 7.6 0.6 F 17,192 1,971 17,802 0.6 8.9 7.82 8.6 0.8 G 21,492 806 5,254 2.0 8.9 8.32 9.1 0.8 H 25,902 801 6,718 1.5 10.4 10.4 11.4 1.0 I 28,892 941 8,686 1.2 11.9 11.9 12.9 1.0 J 33,392 820 8,455 1.2 13.2 13.2 14.2 1.0 K 36,492 1,324 11,577 0.9 14.0 14.0 15.0 1.0 L 38,842 1,346 10,788 1.0 14.5 14.5 15.5 1.0 1Feet above mouth at East Bay 2Elevation computed without consideration of East Bay storm surge effects
TABLE 24
FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SANTA ROSA COUNTY, FL
FLOODING SOURCE: EAST BAY RIVER AND INCORPORATED AREAS
83
LOCATION FLOODWAY 1% ANNUAL CHANCE FLOOD WATER SURFACE
ELEVATION (FEET NAVD88)
CROSS SECTION DISTANCE1 WIDTH3
(FEET)
SECTION AREA
(SQ. FEET)
MEAN VELOCITY
(FEET/SEC) REGULATORY WITHOUT
FLOODWAY WITH
FLOODWAY INCREASE
A 260 11,754 36,963 5.7 11.0 1.52 2.4 0.9 B 9,610 13,210 130,016 1.6 11.0 8.42 8.7 0.3 C 14,210 11,092 138,573 1.5 11.0 10.82 11.3 0.5 D 23,510 8,356 139,970 1.5 15.1 15.1 16.1 1.0 E 30,970 9,500 179,667 1.2 17.9 18.1 18.8 0.9 F 39,920 10,890 191,767 1.1 20.1 20.3 20.9 0.8 G 50,110 12,510 244,300 0.9 22.2 22.4 23.1 0.9 H 56,790 9,645 181,617 1.2 23.3 23.5 24.4 0.9 I 64,350 8,944 167,470 1.3 25.0 25.2 25.8 0.8 J 66,500 5,607 72,627 2.2 25.8 25.8 26.8 1.0 K 73,502 13,330 287,920 0.6 26.5 26.5 27.5 1.0 L 80,602 11,236 221,985 0.7 27.0 27.0 28.0 1.0 M 87,632 12,431 233,338 0.7 27.7 27.7 28.7 1.0 N 97,812 11,363 229,219 0.7 28.7 28.7 29.7 1.0 O 111,852 13,812 274,559 0.6 29.5 29.5 30.5 1.0 P 125,662 15,659 279,608 0.6 30.2 30.2 31.2 1.0 Q 143,062 9,964 142,340 1.1 31.7 31.7 32.7 1.0 R 150,242 9,397 154,267 1.0 33.6 33.6 34.6 1.0 S 163,342 11,869 204,753 0.8 35.8 35.8 36.8 1.0 T 173,042 10,237 150,152 1.0 37.5 37.5 38.5 1.0 U 179,742 5,863 98,286 1.6 39.6 39.6 40.6 1.0 V 193,392 7,136 118,512 1.3 44.4 44.4 45.4 1.0 W 200,492 10,827 198,320 0.8 45.8 45.8 46.8 1.0 X 211,172 15,785 267,611 0.6 46.9 46.9 47.9 1.0 Y 217,572 10,560 166,225 0.9 47.6 47.6 48.6 1.0 Z 222,972 7,733 102,943 1.5 48.8 48.8 49.8 1.0 1Feet above U.S. route 90 3Width extends beyond county boundary 2Elevation computed without consideration of Escambia Bay storm surge effects
TABLE 24
FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SANTA ROSA COUNTY, FL
FLOODING SOURCE: ESCAMBIA RIVER AND INCORPORATED AREAS
84
LOCATION FLOODWAY 1% ANNUAL CHANCE FLOOD WATER SURFACE
ELEVATION (FEET NAVD88)
CROSS SECTION DISTANCE1 WIDTH2
(FEET)
SECTION AREA
(SQ. FEET)
MEAN VELOCITY
(FEET/SEC) REGULATORY WITHOUT
FLOODWAY WITH
FLOODWAY INCREASE
AA 235,122 8,844 130,894 1.2 52.4 52.4 53.4 1.0 AB 243,542 8,008 133,538 1.1 54.4 54.4 55.4 1.0 AC 253,392 8,617 150,661 1.0 56.4 56.4 57.4 1.0 AD 261,042 8,022 142,296 1.1 57.6 57.6 58.6 1.0 AE 269,291 8,694 94,530 1.5 58.9 58.9 59.9 1.0 1Feet above U.S. route 90 2Width extends beyond county boundary
TABLE 24
FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SANTA ROSA COUNTY, FL
FLOODING SOURCE: ESCAMBIA RIVER AND INCORPORATED AREAS
85
LOCATION FLOODWAY 1% ANNUAL CHANCE FLOOD WATER SURFACE
ELEVATION (FEET NAVD88)
CROSS SECTION DISTANCE1 WIDTH
(FEET)
SECTION AREA
(SQ. FEET)
MEAN VELOCITY
(FEET/SEC) REGULATORY WITHOUT
FLOODWAY WITH
FLOODWAY INCREASE
A 5,801 513 2,058 4.5 11.6 10.02 11.0 1.0 B 7,987 349 1,063 5.4 14.6 14.6 15.0 0.4 C 8,153 363 2,276 3.2 17.8 17.8 18.3 0.5 D 11,417 108 638 10.1 38.2 38.2 39.0 0.8 E 14,183 290 1,354 6.0 52.4 52.4 53.3 0.9 F 15,807 175 784 5.6 61.1 61.1 61.6 0.5 G 15,876 175 1,425 3.2 64.3 64.3 65.3 1.0 H 19,148 149 831 6.3 75.4 75.4 76.4 1.0 I 21,191 170 880 5.8 86.3 86.3 87.1 0.8 J 21,265 170 1,390 5.0 89.5 89.5 90.4 0.9 K 22,708 103 361 3.4 91.0 91.0 91.8 0.8 L 23,617 95 266 5.7 95.1 95.1 95.2 0.1 M 23,695 100 874 1.8 100.3 100.3 101.2 0.9 N 24,612 50 132 9.2 101.5 101.5 101.8 0.3 O 25,751 93 262 4.7 110.0 110.0 110.3 0.3 P 25,863 86 445 3.0 113.3 113.3 114.3 1.0 Q 27,111 32 137 8.9 127.2 127.4 127.7 0.3 1Feet above mouth at Escambia Bay 2Elevation computed without consideration of Escambia Bay storm surge effects
TABLE 24
FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SANTA ROSA COUNTY, FL
FLOODING SOURCE: PACE MILL CREEK AND INCORPORATED AREAS
86
LOCATION FLOODWAY 1% ANNUAL CHANCE FLOOD WATER SURFACE
ELEVATION (FEET NAVD88)
CROSS SECTION DISTANCE1 WIDTH
(FEET)
SECTION AREA
(SQ. FEET)
MEAN VELOCITY
(FEET/SEC) REGULATORY WITHOUT
FLOODWAY WITH
FLOODWAY INCREASE
A 4,370 481 6,327 4.3 9.8 6.92 7.6 0.7 B 6,775 286 3,372 10.0 9.8 7.72 8.5 0.8 C 6,889 256 3,405 9.5 9.8 8.92 9.5 0.6 D 10,108 1,564 10,773 3.8 12.2 12.2 12.7 0.5 E 13,133 404 4,992 9.5 13.3 13.3 14.0 0.7 F 13,268 431 5,678 8.6 14.9 14.9 15.1 0.2 G 14,352 1,286 10,598 7.2 15.7 15.7 16.7 1.0 H 15,669 1,537 18,269 4.2 16.8 16.8 17.8 1.0 I 18,389 1,210 12,295 5.1 18.0 18.0 19.0 1.0 J 23,254 778 9,372 5.9 22.1 22.1 23.1 1.0 K 25,016 1,359 11,129 6.0 24.1 24.1 25.0 0.9 L 30,373 1,070 10,383 5.5 29.1 29.1 30.0 0.9 M 32,268 973 12,088 4.0 30.4 30.4 31.2 0.8 N 33,216 1,151 13,349 4.3 30.8 30.8 31.6 0.8 O 35,720 1,222 15,925 3.3 31.7 31.7 32.5 0.8 P 39,348 1,071 9,717 5.6 33.5 33.5 34.3 0.8 Q 39,427 1,071 9,959 5.5 33.7 33.7 34.6 0.9 R 40,496 1,250 8,221 8.9 35.5 35.5 36.3 0.8 S 44,985 812 9,725 6.1 42.3 42.3 43.0 0.7 T 45,461 850 11,927 4.6 42.6 42.6 43.4 0.8 U 48,988 707 8,896 3.9 44.7 44.7 45.7 1.0 V 51,399 809 9,254 5.2 46.8 46.8 47.8 1.0 W 53,324 565 5,208 6.1 48.8 48.8 49.6 0.8 X 53,463 545 5,377 5.9 49.3 49.3 50.2 0.9 Y 54,091 400 4,825 9.1 50.4 50.4 51.1 0.7 Z 54,639 669 7,530 5.9 51.4 51.4 52.3 0.9 1Feet above mouth at Blackwater River 2Elevation computed without consideration of Blackwater Bay storm surge effects
TABLE 24
FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SANTA ROSA COUNTY, FL
FL6.OODING SOURCE: POND CREEK AND INCORPORATED AREAS
87
LOCATION FLOODWAY 1% ANNUAL CHANCE FLOOD WATER SURFACE
ELEVATION (FEET NAVD88)
CROSS SECTION DISTANCE1 WIDTH
(FEET)
SECTION AREA
(SQ. FEET)
MEAN VELOCITY
(FEET/SEC) REGULATORY WITHOUT
FLOODWAY WITH
FLOODWAY INCREASE
AA 55,245 653 6,954 6.6 52.1 52.1 52.9 0.8 AB 58,228 761 7,121 7.2 56.2 56.2 57.2 1.0 AC 61,641 710 8,201 5.8 60.1 60.1 61.0 0.9 AD 65,620 1,199 11,040 5.0 63.7 63.7 64.6 0.9 AE 66,421 1,511 9,341 6.5 64.6 64.6 65.3 0.7 AF 69,258 1,046 7,590 4.0 67.0 67.0 67.7 0.7 AG 69,388 1,046 8,514 3.7 67.7 67.7 68.6 0.9 AH – AT2 1Feet above mouth at Blackwater River 2Floodway data not computed, see Table 25 for elevations
TABLE 24
FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SANTA ROSA COUNTY, FL
FLOODING SOURCE: POND CREEK AND INCORPORATED AREAS
88
LOCATION FLOODWAY 1% ANNUAL CHANCE FLOOD WATER SURFACE
ELEVATION (FEET NAVD88)
CROSS SECTION DISTANCE1 WIDTH
(FEET)
SECTION AREA
(SQ. FEET)
MEAN VELOCITY
(FEET/SEC) REGULATORY WITHOUT
FLOODWAY WITH
FLOODWAY INCREASE
A 10,736 7,168 27,383 3.1 9.2 5.42 5.8 0.4 B 27,462 8,709 104,290 0.8 13.8 13.8 14.3 0.5 C 33,390 4,792 67,440 1.3 15.5 15.5 16.0 0.5 D 33,496 7,792 66,198 1.3 15.6 15.6 16.1 0.5 E 43,293 7,329 90,711 0.9 16.9 16.9 17.4 0.5 F 51,322 8,731 113,669 0.7 18.4 18.4 18.9 0.5 G 58,514 5,841 79,198 1.0 20.2 20.2 20.7 0.5 H 66,628 5,231 79,414 1.0 22.6 22.6 23.1 0.5 I 81,427 6,118 88,489 0.9 24.7 24.7 25.3 0.6 J 87,896 5,863 77,674 1.0 27.0 27.0 27.6 0.6 K 96,564 4,124 67,502 1.2 28.9 28.9 29.4 0.5 L 103,524 5,476 82,647 0.9 30.3 30.3 30.8 0.5 M 109,668 6,786 100,699 0.8 31.5 31.5 32.0 0.5 N3 113,349 7,073 84,793 0.9 31.9 31.9 32.4 0.5
1Feet above mouth at Blackwater Bay 2Elevation computed without consideration of Blackwater Bay storm surge effects
3Floodway is shown outside of the county boundary
TABLE 24
FEDERAL EMERGENCY MANAGEMENT AGENCY FLOODWAY DATA SANTA ROSA COUNTY, FL
FLOODING SOURCE: YELLOW RIVER AND INCORPORATED AREAS
89
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Beale Creek 94 11,605 * 11.8 N/A N/A
Beale Creek 93 12,127 * 13.8 N/A N/A
Beale Creek 92 12,334 * 14.3 N/A N/A
Beale Creek 91 12,381 * 14.3 N/A N/A
Beale Creek 90 12,471 * 14.6 N/A N/A
Beale Creek 89 12,561 * 16.5 N/A N/A
Beale Creek 88 12,722 * 17.9 N/A N/A
Beale Creek 87 12,882 * 18.5 N/A N/A
Beale Creek 86 13,237 * 19.1 N/A N/A
Beale Creek 85 13,289 * 19.1 N/A N/A
Beale Creek 84 13,450 * 19.7 N/A N/A
Beale Creek A 14,142 * 24.4 N/A N/A
Beale Creek B 15,153 * 28.2 N/A N/A
Beale Creek 81 15,723 * 31.5 N/A N/A
Beale Creek 80 16,392 * 37.2 N/A N/A
Beale Creek 79 16,562 * 38.6 N/A N/A
Beale Creek C 16,647 * 39.8 N/A N/A
Beale Creek 77 16,707 * 39.8 N/A N/A
Beale Creek 76 17,300 * 40.6 N/A N/A
Beale Creek D 17,596 * 43.7 N/A N/A
Beale Creek 74 17,950 * 46.0 N/A N/A
Beale Creek 73 18,657 * 52.4 N/A N/A
Beale Creek E 19,875 * 61.9 N/A N/A Big Coldwater Creek 930 0 * 23.8 N/A N/A
Big Coldwater Creek 929 2,392 * 23.8 N/A N/A
Big Coldwater Creek 928 4,520 * 23.8 N/A N/A
Big Coldwater Creek A 6,511 * 23.8 N/A N/A
90
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right Big Coldwater Creek 926 8,184 * 23.8 N/A N/A
Big Coldwater Creek 925 10,425 * 23.8 N/A N/A
Big Coldwater Creek B 12,405 * 24.2 N/A N/A
Big Coldwater Creek 923 14,354 * 25.1 N/A N/A
Big Coldwater Creek 922 15,840 * 25.7 N/A N/A
Big Coldwater Creek 921 16,958 * 26.1 N/A N/A
Big Coldwater Creek 920 17,539 * 26.6 N/A N/A
Big Coldwater Creek C 17,651 * 27.5 N/A N/A
Big Coldwater Creek 918 17,960 * 27.6 N/A N/A
Big Coldwater Creek 917 20,200 * 28.3 N/A N/A
Big Coldwater Creek D 22,671 * 29.0 N/A N/A
Big Coldwater Creek 915 25,475 * 30.8 N/A N/A
Big Coldwater Creek E 28,029 * 32.5 N/A N/A
Big Coldwater Creek 913 30,083 * 33.3 N/A N/A
Big Coldwater Creek 912 32,273 * 34.0 N/A N/A
Big Coldwater Creek F 34,265 * 34.9 N/A N/A
Big Coldwater Creek 910 36,343 * 35.7 N/A N/A
Big Coldwater Creek 909 38,354 * 36.6 N/A N/A
Big Coldwater Creek G 39,657 * 37.6 N/A N/A
Big Coldwater Creek 100 40,676 * 38.1 N/A N/A
Big Coldwater Creek 101 41,242 * 38.2 N/A N/A
Big Coldwater Creek 102 42,234 * 38.7 N/A N/A
91
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right Big Coldwater Creek 103 43,738 * 39.2 N/A N/A
Big Coldwater Creek H 44,657 * 39.8 N/A N/A
Big Coldwater Creek 105 45,655 * 40.5 N/A N/A
Big Coldwater Creek 106 46,654 * 41.0 N/A N/A
Big Coldwater Creek 107 47,655 * 42.0 N/A N/A
Big Coldwater Creek 108 48,654 * 42.8 N/A N/A
Big Coldwater Creek 109 49,497 * 43.3 N/A N/A
Big Coldwater Creek I 50,656 * 43.6 N/A N/A
Big Coldwater Creek 111 51,378 * 43.8 N/A N/A
Big Coldwater Creek 112 52,109 * 44.3 N/A N/A
Big Coldwater Creek 113 53,655 * 44.8 N/A N/A
Big Coldwater Creek 114 54,653 * 45.1 N/A N/A
Big Coldwater Creek 115 55,653 * 46.5 N/A N/A
Big Coldwater Creek J 56,651 * 48.5 N/A N/A
Big Coldwater Creek 117 57,642 * 49.9 N/A N/A
Big Coldwater Creek 118 58,556 * 50.3 N/A N/A
Big Coldwater Creek 119 59,655 * 50.4 N/A N/A
Big Coldwater Creek 120 60,651 * 50.7 N/A N/A
Big Coldwater Creek K 61,077 * 50.8 N/A N/A
Blackwater River 613 100,371 * 37.9 N/A N/A
Blackwater River 612 100,476 * 38.0 N/A N/A
Blackwater River 611 100,825 * 38.1 N/A N/A
Blackwater River 610 101,496 * 38.4 N/A N/A
92
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Blackwater River 609 102,797 * 39.0 N/A N/A
Blackwater River AA 103,473 * 39.3 N/A N/A
Blackwater River 607 104,390 * 39.7 N/A N/A
Blackwater River AB 105,593 * 40.6 N/A N/A
Blackwater River 605 107,484 * 41.7 N/A N/A
Blackwater River 604 108,504 * 42.4 N/A N/A
Blackwater River AC 111,459 * 43.5 N/A N/A
Blackwater River 602 112,474 * 44.3 N/A N/A
Blackwater River 601 112,994 * 44.7 N/A N/A
Blackwater River AD 116,529 * 46.3 N/A N/A
Blackwater River 599 116,820 * 46.5 N/A N/A
Blackwater River 598 118,220 * 47.1 N/A N/A
Blackwater River 597 119,114 * 47.6 N/A N/A
Blackwater River AE 119,914 * 48.1 N/A N/A
Blackwater River 595 121,035 * 48.5 N/A N/A
Blackwater River 594 121,949 * 48.8 N/A N/A
Blackwater River 593 122,884 * 49.2 N/A N/A
Blackwater River AF 123,825 * 49.5 N/A N/A
Blackwater River 591 125,416 * 49.9 N/A N/A
Blackwater River 590 127,143 * 50.3 N/A N/A
Blackwater River AG 128,077 * 50.6 N/A N/A
Blackwater River 588 129,046 * 51.1 N/A N/A
Blackwater River 587 129,985 * 51.3 N/A N/A
Blackwater River 586 131,243 * 51.6 N/A N/A
Blackwater River AH 133,378 * 52.0 N/A N/A
Blackwater River 584 134,505 * 52.4 N/A N/A
Blackwater River 583 135,369 * 52.9 N/A N/A
Blackwater River AI 136,277 * 53.4 N/A N/A
Blackwater River 581 137,431 * 54.0 N/A N/A
93
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Blackwater River 580 138,344 * 54.4 N/A N/A
Blackwater River 579 139,543 * 54.9 N/A N/A
Blackwater River AJ 140,562 * 55.5 N/A N/A
Blackwater River 577 141,409 * 55.8 N/A N/A
Blackwater River AK 145,563 * 57.1 N/A N/A
Blackwater River 575 145,823 * 57.3 N/A N/A
Blackwater River 574 146,832 * 57.5 N/A N/A
Blackwater River AL 147,370 * 57.6 N/A N/A
Blackwater River AM 147,427 * 57.6 N/A N/A
Blackwater River 571 148,124 * 57.9 N/A N/A
Blackwater River 570 149,031 * 58.2 N/A N/A
Blackwater River 569 149,714 * 58.5 N/A N/A
Blackwater River AN 150,858 * 59.1 N/A N/A
Blackwater River 567 152,137 * 59.6 N/A N/A
Blackwater River 566 153,054 * 60.1 N/A N/A
Blackwater River AO 155,016 * 60.9 N/A N/A
Blackwater River 564 156,391 * 61.2 N/A N/A
Blackwater River 563 157,485 * 61.6 N/A N/A
Blackwater River AP 158,349 * 62.0 N/A N/A
Blackwater River 561 159,777 * 62.6 N/A N/A
Blackwater River 560 160,557 * 62.9 N/A N/A
Blackwater River AQ 162,478 * 63.3 N/A N/A
Blackwater River 558 164,134 * 64.0 N/A N/A
Blackwater River 557 164,781 * 64.3 N/A N/A
Blackwater River 556 165,927 * 64.9 N/A N/A
Blackwater River AR 167,062 * 65.5 N/A N/A
Blackwater River 554 167,895 * 65.8 N/A N/A
Blackwater River 553 168,708 * 66.1 N/A N/A
Blackwater River 552 169,629 * 66.6 N/A N/A
94
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Blackwater River AS 170,370 * 67.0 N/A N/A
Blackwater River 550 171,672 * 67.6 N/A N/A
Blackwater River 549 172,482 * 68.0 N/A N/A
Blackwater River AT 173,528 * 68.4 N/A N/A
Blackwater River 547 174,445 * 69.0 N/A N/A
Blackwater River 546 175,255 * 69.5 N/A N/A
Blackwater River AU 176,677 * 70.2 N/A N/A
Blackwater River 886 177,436 * 70.6 N/A N/A
Blackwater River 544 178,377 * 70.9 N/A N/A
Bray Mill Creek 710 1,969 * 49.8 N/A N/A
Bray Mill Creek 709 2,944 * 54.3 N/A N/A
Bray Mill Creek 713 3,857 * 61.9 N/A N/A
Bray Mill Creek 712 4,018 * 63.5 N/A N/A
Bray Mill Creek 711 4,088 * 65.5 N/A N/A
Bray Mill Creek 716 4,186 * 65.6 N/A N/A
Bray Mill Creek 715 4,853 * 68.4 N/A N/A
Bray Mill Creek 714 4,939 * 68.7 N/A N/A
Bray Mill Creek 717 5,953 * 72.2 N/A N/A
Bray Mill Creek 721 6,956 * 78.0 N/A N/A
Bray Mill Creek 720 7,986 * 82.2 N/A N/A
Bray Mill Creek 719 8,997 * 86.5 N/A N/A
Bray Mill Creek 718 9,876 * 93.2 N/A N/A
Bray Mill Creek 725 10,861 * 97.8 N/A N/A
Bray Mill Creek 724 11,974 * 104.0 N/A N/A
Bray Mill Creek 723 12,999 * 108.2 N/A N/A
Bray Mill Creek 722 14,033 * 116.3 N/A N/A
Bray Mill Creek 729 15,084 * 131.6 N/A N/A
Bray Mill Creek 728 16,114 * 146.2 N/A N/A
Bray Mill Creek 727 16,914 * 164.4 N/A N/A
95
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Bray Mill Creek 726 17,856 * 184.5 N/A N/A
Clear Creek 908 0 * 18.2 N/A N/A
Clear Creek 907 1,265 * 18.2 N/A N/A
Clear Creek 906 2,538 * 18.2 N/A N/A
Clear Creek 905 2,861 * 18.2 N/A N/A
Clear Creek 904 3,196 * 18.2 N/A N/A
Clear Creek 903 3,227 * 18.2 N/A N/A
Clear Creek 902 3,611 * 18.2 N/A N/A
Clear Creek 901 4,376 * 18.2 N/A N/A
Clear Creek 900 4,439 * 18.2 N/A N/A
Clear Creek 899 4,836 * 18.2 N/A N/A
Clear Creek 898 5,164 * 18.2 N/A N/A
Clear Creek 897 5,859 * 18.2 N/A N/A
Clear Creek 896 6,258 * 18.2 N/A N/A
Clear Creek 895 6,544 * 18.2 N/A N/A
Clear Creek 894 6,711 * 18.2 N/A N/A
Clear Creek A 7,201 * 18.2 N/A N/A
Clear Creek 892 9,362 * 18.2 N/A N/A
Clear Creek 891 11,364 * 18.2 N/A N/A
Clear Creek B 13,197 * 19.1 N/A N/A
Clear Creek 889 15,093 * 21.6 N/A N/A
Clear Creek C 16,396 * 23.4 N/A N/A
Clear Creek 123 17,984 * 26.0 N/A N/A
Clear Creek 124 19,746 * 28.7 N/A N/A
Clear Creek D 21,122 * 31.9 N/A N/A
Clear Creek 126 22,222 * 35.2 N/A N/A
Clear Creek 127 24,094 * 36.3 N/A N/A
Clear Creek 128 25,667 * 37.0 N/A N/A
Clear Creek E 27,093 * 40.3 N/A N/A
96
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Clear Creek 130 28,766 * 43.1 N/A N/A
Clear Creek 131 30,091 * 45.4 N/A N/A
Clear Creek 132 30,344 * 46.0 N/A N/A
Clear Creek 133 30,643 * 47.3 N/A N/A
Clear Creek 134 30,741 * 49.1 N/A N/A
Clear Creek F 31,029 * 49.6 N/A N/A
Clear Creek 136 32,750 * 51.2 N/A N/A
Clear Creek 137 34,062 * 55.6 N/A N/A
Clear Creek 138 34,283 * 56.8 N/A N/A
Clear Creek G 34,369 * 58.1 N/A N/A
Clear Creek 140 34,549 * 58.2 N/A N/A
Clear Creek 141 35,119 * 58.2 N/A N/A
Clear Creek 142 35,353 * 58.2 N/A N/A
Clear Creek 143 35,565 * 58.3 N/A N/A
Clear Creek 144 37,122 * 58.3 N/A N/A
Clear Creek H 38,405 * 58.6 N/A N/A
Clear Creek 146 39,921 * 60.1 N/A N/A
Clear Creek 147 41,298 * 61.7 N/A N/A
Clear Creek I 41,389 * 68.6 N/A N/A
Clear Creek 149 42,792 * 68.6 N/A N/A
Clear Creek 150 44,132 * 69.0 N/A N/A
Clear Creek 151 45,137 * 76.4 N/A N/A
Clear Creek 152 45,467 * 77.0 N/A N/A
Clear Creek 153 45,556 * 77.0 N/A N/A
Clear Creek 154 46,643 * 77.0 N/A N/A
Clear Creek J 47,298 * 77.1 N/A N/A
Clear Creek 156 48,923 * 77.8 N/A N/A
Clear Creek 157 50,275 * 91.3 N/A N/A
Clear Creek 158 51,078 * 110.2 N/A N/A
97
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Clear Creek K 51,600 * 127.2 N/A N/A East Fork Big Coldwater Creek A 3,229 * 51.5 N/A N/A
East Fork Big Coldwater Creek 165 3,975 * 51.8 N/A N/A
East Fork Big Coldwater Creek 164 4,977 * 52.2 N/A N/A
East Fork Big Coldwater Creek 163 5,327 * 52.4 N/A N/A
East Fork Big Coldwater Creek 162 5,454 * 52.5 N/A N/A
East Fork Big Coldwater Creek B 5,952 * 52.7 N/A N/A
East Fork Big Coldwater Creek 160 6,671 * 52.9 N/A N/A
East Fork Big Coldwater Creek 201 7,740 * 53.2 N/A N/A
East Fork Big Coldwater Creek 200 8,722 * 53.7 N/A N/A
East Fork Big Coldwater Creek 199 9,722 * 54.5 N/A N/A
East Fork Big Coldwater Creek 198 10,605 * 55.4 N/A N/A
East Fork Big Coldwater Creek C 11,546 * 56.0 N/A N/A
East Fork Big Coldwater Creek 196 12,191 * 56.3 N/A N/A
East Fork Big Coldwater Creek 195 13,455 * 57.3 N/A N/A
East Fork Big Coldwater Creek 194 14,275 * 58.3 N/A N/A
East Fork Big Coldwater Creek 193 15,447 * 59.0 N/A N/A
East Fork Big Coldwater Creek D 16,448 * 59.7 N/A N/A
East Fork Big Coldwater Creek 191 17,382 * 60.2 N/A N/A
East Fork Big Coldwater Creek 190 18,146 * 60.7 N/A N/A
East Fork Big Coldwater Creek 189 18,933 * 61.0 N/A N/A
East Fork Big Coldwater Creek 188 20,042 * 61.9 N/A N/A
98
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right East Fork Big Coldwater Creek 187 20,988 * 62.7 N/A N/A
East Fork Big Coldwater Creek E 21,998 * 63.3 N/A N/A
East Fork Big Coldwater Creek 185 22,979 * 64.2 N/A N/A
East Fork Big Coldwater Creek 184 23,818 * 64.9 N/A N/A
East Fork Big Coldwater Creek 183 24,826 * 65.3 N/A N/A
East Fork Big Coldwater Creek 182 25,716 * 65.8 N/A N/A
East Fork Big Coldwater Creek 181 26,640 * 66.2 N/A N/A
East Fork Big Coldwater Creek F 27,605 * 66.6 N/A N/A
East Fork Big Coldwater Creek 179 28,570 * 67.4 N/A N/A
East Fork Big Coldwater Creek 178 29,562 * 68.3 N/A N/A
East Fork Big Coldwater Creek 177 30,593 * 69.1 N/A N/A
East Fork Big Coldwater Creek 176 31,372 * 69.9 N/A N/A
East Fork Big Coldwater Creek G 32,527 * 71.1 N/A N/A
East Fork Big Coldwater Creek 174 33,552 * 71.5 N/A N/A
East Fork Big Coldwater Creek 173 34,681 * 71.9 N/A N/A
East Fork Big Coldwater Creek 172 35,693 * 72.9 N/A N/A
East Fork Big Coldwater Creek 171 36,345 * 73.6 N/A N/A
East Fork Big Coldwater Creek H 36,493 * 74.0 N/A N/A
East Fork Big Coldwater Creek 169 36,966 * 74.3 N/A N/A
East Fork Big Coldwater Creek 168 37,702 * 75.3 N/A N/A
East Fork Big Coldwater Creek I 38,778 * 76.1 N/A N/A
Escambia River C 14,210 * 11.0 N/A N/A
99
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Escambia River D 23,510 * 15.1 N/A N/A
Escambia River E 30,970 * 17.9 N/A N/A
Escambia River F 39,920 * 20.1 N/A N/A
Jacobs Creek 275 1,279 * 23.0 N/A N/A
Jacobs Creek A 1,688 * 28.4 N/A N/A
Jacobs Creek 273 2,323 * 32.6 N/A N/A
Jacobs Creek 272 2,990 * 37.0 N/A N/A
Jacobs Creek 271 3,086 * 38.1 N/A N/A
Jacobs Creek 270 3,182 * 38.8 N/A N/A
Jacobs Creek B 3,240 * 40.3 N/A N/A
Jacobs Creek 268 3,351 * 40.4 N/A N/A
Jacobs Creek 267 3,987 * 41.7 N/A N/A
Jacobs Creek C 4,139 * 44.2 N/A N/A
Jacobs Creek 265 4,415 * 44.3 N/A N/A
Jacobs Creek D 5,111 * 47.0 N/A N/A
Juniper Creek A 1,357 * 84.3 N/A N/A
Juniper Creek 233 2,173 * 84.5 N/A N/A
Juniper Creek 232 2,906 * 85.3 N/A N/A
Juniper Creek 231 3,534 * 86.2 N/A N/A
Juniper Creek 230 4,473 * 87.6 N/A N/A
Juniper Creek 229 5,050 * 88.4 N/A N/A
Juniper Creek 228 5,885 * 90.2 N/A N/A
Juniper Creek B 6,638 * 92.1 N/A N/A
Juniper Creek 226 7,193 * 93.1 N/A N/A
Juniper Creek 225 7,927 * 94.4 N/A N/A
Juniper Creek 224 9,021 * 95.6 N/A N/A
Juniper Creek 223 9,873 * 96.7 N/A N/A
Juniper Creek 222 10,855 * 98.5 N/A N/A
Juniper Creek C 11,822 * 100.5 N/A N/A
100
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Juniper Creek 220 12,815 * 102.8 N/A N/A
Juniper Creek 219 13,631 * 104.5 N/A N/A
Juniper Creek 218 14,576 * 106.2 N/A N/A
Juniper Creek 217 14,954 * 106.9 N/A N/A
Juniper Creek 216 15,751 * 107.7 N/A N/A
Juniper Creek 215 16,747 * 109.0 N/A N/A
Juniper Creek D 17,348 * 109.8 N/A N/A
Juniper Creek 213 18,263 * 110.7 N/A N/A
Juniper Creek 212 19,314 * 112.6 N/A N/A
Juniper Creek 211 20,331 * 115.5 N/A N/A
Juniper Creek 210 21,353 * 117.5 N/A N/A
Juniper Creek 209 21,804 * 118.2 N/A N/A
Juniper Creek E 21,885 * 121.1 N/A N/A
Juniper Creek 207 22,146 * 121.3 N/A N/A
Juniper Creek 206 22,662 * 121.6 N/A N/A
Juniper Creek 205 23,398 * 122.1 N/A N/A
Juniper Creek 204 24,513 * 125.4 N/A N/A
Juniper Creek 203 25,495 * 128.3 N/A N/A
Juniper Creek F 26,475 * 130.2 N/A N/A
Juniper Creek 863 27,632 * 132.8 N/A N/A
Juniper Creek 862 28,814 * 134.6 N/A N/A
Juniper Creek 861 30,077 * 136.8 N/A N/A
Juniper Creek 860 31,305 * 140.3 N/A N/A
Juniper Creek 859 32,265 * 142.6 N/A N/A
Juniper Creek 858 33,291 * 144.7 N/A N/A
Juniper Creek 857 34,208 * 147.3 N/A N/A
Juniper Creek 856 35,153 * 150.7 N/A N/A
Juniper Creek 855 36,185 * 153.4 N/A N/A
Juniper Creek 854 36,533 * 154.1 N/A N/A
101
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Juniper Creek 853 36,881 * 155.0 N/A N/A
Juniper Creek 852 36,918 * 156.2 N/A N/A
Juniper Creek 851 37,258 * 156.6 N/A N/A
Juniper Creek 850 38,191 * 158.5 N/A N/A
Juniper Creek 849 39,185 * 161.6 N/A N/A
Juniper Creek 848 40,137 * 164.3 N/A N/A
Juniper Creek 847 41,080 * 166.4 N/A N/A
Juniper Creek 846 41,528 * 168.5 N/A N/A
Long Branch 881 2,255 * 37.9 N/A N/A
Long Branch 880 2,705 * 39.8 N/A N/A
Long Branch 879 2,950 * 41.9 N/A N/A
Long Branch 878 3,073 * 42.8 N/A N/A
Long Branch 877 3,121 * 44.1 N/A N/A
Long Branch 876 3,330 * 44.2 N/A N/A
Long Branch 875 3,755 * 44.5 N/A N/A
Long Branch 874 4,070 * 44.9 N/A N/A
Long Branch 873 4,157 * 47.8 N/A N/A
Long Branch 872 5,133 * 47.8 N/A N/A
Long Branch 871 6,086 * 52.7 N/A N/A
Long Branch 870 7,281 * 56.1 N/A N/A
Long Branch 869 7,575 * 58.5 N/A N/A
Long Branch 868 7,705 * 61.1 N/A N/A
Long Branch 867 7,974 * 61.2 N/A N/A
Long Branch 866 11,331 * 71.7 N/A N/A
Long Branch 865 12,877 * 77.4 N/A N/A
Long Branch 864 14,178 * 85.1 N/A N/A
Malloy Branch 780 49 * 115.3 N/A N/A
Malloy Branch 779 576 * 115.5 N/A N/A
Malloy Branch 778 1,278 * 115.9 N/A N/A
102
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Malloy Branch 777 2,012 * 120.3 N/A N/A
Malloy Branch 776 2,352 * 121.8 N/A N/A
Malloy Branch 775 2,397 * 123.1 N/A N/A
Malloy Branch 774 2,701 * 123.3 N/A N/A
Malloy Branch 773 4,291 * 125.0 N/A N/A
Malloy Branch 772 5,160 * 128.2 N/A N/A
Malloy Branch 771 7,050 * 131.0 N/A N/A
Malloy Branch 770 8,537 * 136.0 N/A N/A
Malloy Branch 769 9,724 * 139.2 N/A N/A
Malloy Branch 768 10,825 * 142.7 N/A N/A
Malloy Branch 767 12,041 * 147.2 N/A N/A
Malloy Branch 766 13,520 * 152.3 N/A N/A
Malloy Branch 765 14,528 * 155.6 N/A N/A
Malloy Branch 764 15,568 * 161.0 N/A N/A
Malloy Branch 763 16,675 * 167.7 N/A N/A
Malloy Branch 762 17,568 * 170.7 N/A N/A
Malloy Branch 761 18,817 * 175.7 N/A N/A
Malloy Branch 760 19,190 * 178.9 N/A N/A
Malloy Branch 759 19,517 * 183.5 N/A N/A
Malloy Branch 758 19,553 * 186.7 N/A N/A
Malloy Branch 757 19,845 * 186.9 N/A N/A
Malloy Branch 756 20,608 * 187.0 N/A N/A
Malloy Branch 755 20,907 * 188.9 N/A N/A
Malloy Branch 754 20,934 * 190.7 N/A N/A
Malloy Branch 753 21,146 * 190.8 N/A N/A
Malloy Branch 752 21,871 * 192.5 N/A N/A
Malloy Branch 751 22,253 * 194.7 N/A N/A
Malloy Branch 750 22,569 * 196.8 N/A N/A
Malloy Branch 749 22,594 * 197.9 N/A N/A
103
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Malloy Branch 748 22,789 * 198.2 N/A N/A
Malloy Branch 747 22,996 * 199.0 N/A N/A
Malloy Branch 746 24,182 * 204.9 N/A N/A
Malloy Branch 745 25,267 * 212.2 N/A N/A
Malloy Branch 744 25,980 * 218.1 N/A N/A
Malloy Branch 743 26,116 * 220.5 N/A N/A
Malloy Branch 742 26,983 * 224.8 N/A N/A
Malloy Branch 741 27,759 * 227.4 N/A N/A
Manning Creek A 2,628 * 56.4 N/A N/A
Manning Creek 239 2,942 * 56.4 N/A N/A
Manning Creek 238 2,967 * 56.4 N/A N/A
Manning Creek 237 3,621 * 57.1 N/A N/A
Manning Creek 236 4,837 * 58.7 N/A N/A
Manning Creek 235 5,818 * 60.3 N/A N/A
Manning Creek B 6,850 * 61.8 N/A N/A
Manning Creek 260 8,522 * 65.0 N/A N/A
Manning Creek 259 8,633 * 66.0 N/A N/A
Manning Creek 258 8,936 * 67.0 N/A N/A
Manning Creek 257 10,309 * 68.3 N/A N/A
Manning Creek C 11,308 * 69.3 N/A N/A
Manning Creek 255 12,605 * 72.2 N/A N/A
Manning Creek 254 13,524 * 72.8 N/A N/A
Manning Creek 253 15,106 * 74.9 N/A N/A
Manning Creek D 16,408 * 76.5 N/A N/A
Manning Creek 262 18,147 * 79.4 N/A N/A
Manning Creek 252 19,303 * 81.2 N/A N/A
Manning Creek 251 20,154 * 82.2 N/A N/A
Manning Creek 250 20,802 * 83.6 N/A N/A
Manning Creek E 22,144 * 86.7 N/A N/A
104
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Manning Creek 248 22,903 * 88.1 N/A N/A
Manning Creek 247 23,520 * 89.4 N/A N/A
Manning Creek 246 24,284 * 91.0 N/A N/A
Manning Creek 245 25,268 * 92.9 N/A N/A
Manning Creek 244 26,277 * 94.7 N/A N/A
Manning Creek 243 27,190 * 95.9 N/A N/A
Manning Creek 242 28,138 * 97.7 N/A N/A
Manning Creek F 28,330 * 98.5 N/A N/A
Pace Mill Creek M3 8,969 * 18.3 N/A N/A
Pond Creek AH 69,525 * 68.8 N/A N/A
Pond Creek 526 70,127 * 69.0 N/A N/A
Pond Creek 525 71,305 * 69.3 N/A N/A
Pond Creek 524 72,556 * 69.7 N/A N/A
Pond Creek 523 73,499 * 70.1 N/A N/A
Pond Creek AI 74,748 * 71.1 N/A N/A
Pond Creek 521 76,785 * 73.7 N/A N/A
Pond Creek 520 79,397 * 76.8 N/A N/A
Pond Creek AJ 82,814 * 80.9 N/A N/A
Pond Creek 519 85,791 * 84.3 N/A N/A
Pond Creek 518 87,127 * 86.7 N/A N/A
Pond Creek AK 89,152 * 89.6 N/A N/A
Pond Creek 516 91,964 * 92.6 N/A N/A
Pond Creek 515 94,649 * 96.0 N/A N/A
Pond Creek 514 96,917 * 98.4 N/A N/A
Pond Creek 513 97,333 * 99.2 N/A N/A
Pond Creek AL 97,394 * 99.5 N/A N/A
Pond Creek 511 97,520 * 99.7 N/A N/A
Pond Creek 510 97,645 * 100.3 N/A N/A
Pond Creek 509 99,549 * 103.6 N/A N/A
105
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Pond Creek 508 100,817 * 105.3 N/A N/A
Pond Creek 507 102,342 * 106.6 N/A N/A
Pond Creek AM 104,309 * 109.2 N/A N/A
Pond Creek 505 106,798 * 111.3 N/A N/A
Pond Creek 504 107,175 * 111.8 N/A N/A
Pond Creek 503 108,600 * 114.6 N/A N/A
Pond Creek 502 109,928 * 116.0 N/A N/A
Pond Creek 501 110,574 * 116.8 N/A N/A
Pond Creek 500 111,267 * 118.5 N/A N/A
Pond Creek AN 111,300 * 118.6 N/A N/A
Pond Creek 498 111,528 * 119.0 N/A N/A
Pond Creek 497 112,475 * 119.7 N/A N/A
Pond Creek 496 113,884 * 120.8 N/A N/A
Pond Creek 495 117,117 * 127.7 N/A N/A
Pond Creek AO 119,412 * 130.1 N/A N/A
Pond Creek 493 121,643 * 131.8 N/A N/A
Pond Creek 492 123,460 * 134.9 N/A N/A
Pond Creek 491 125,832 * 140.2 N/A N/A
Pond Creek 490 127,446 * 146.0 N/A N/A
Pond Creek 489 128,443 * 148.5 N/A N/A
Pond Creek 488 128,813 * 149.7 N/A N/A
Pond Creek AP 128,879 * 151.1 N/A N/A
Pond Creek 486 129,061 * 151.3 N/A N/A
Pond Creek 485 131,273 * 155.6 N/A N/A
Pond Creek 484 133,661 * 162.3 N/A N/A
Pond Creek 483 135,410 * 169.9 N/A N/A
Pond Creek 482 137,764 * 181.3 N/A N/A
Pond Creek AQ 138,256 * 183.7 N/A N/A
Pond Creek 481 138,327 * 183.7 N/A N/A
106
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Pond Creek 480 138,579 * 184.7 N/A N/A
Pond Creek 479 139,546 * 187.8 N/A N/A
Pond Creek 478 141,648 * 191.8 N/A N/A
Pond Creek 477 143,734 * 192.3 N/A N/A
Pond Creek AR 145,534 * 192.8 N/A N/A
Pond Creek 475 147,006 * 194.1 N/A N/A
Pond Creek 474 147,853 * 194.6 N/A N/A
Pond Creek 473 148,699 * 196.7 N/A N/A
Pond Creek 472 149,308 * 197.3 N/A N/A
Pond Creek 471 149,916 * 197.6 N/A N/A
Pond Creek 470 150,525 * 197.7 N/A N/A
Pond Creek 469 151,012 * 197.8 N/A N/A
Pond Creek AS 151,054 * 197.8 N/A N/A
Pond Creek 467 151,306 * 198.0 N/A N/A
Pond Creek 466 152,634 * 198.2 N/A N/A
Pond Creek 465 154,979 * 198.5 N/A N/A
Pond Creek AT 156,209 * 203.0 N/A N/A
Reader Creek 400 535 * 70.0 N/A N/A
Reader Creek 399 1,358 * 70.1 N/A N/A
Reader Creek A 1,402 * 70.2 N/A N/A
Reader Creek 397 1,762 * 70.5 N/A N/A
Reader Creek 396 3,231 * 72.7 N/A N/A
Reader Creek 395 4,231 * 73.9 N/A N/A
Reader Creek 394 5,338 * 75.5 N/A N/A
Reader Creek 393 5,739 * 77.4 N/A N/A
Reader Creek 392 5,778 * 77.6 N/A N/A
Reader Creek 391 6,017 * 78.6 N/A N/A
Reader Creek B 6,576 * 81.7 N/A N/A
Reader Creek 390 7,906 * 85.7 N/A N/A
107
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right
Reader Creek 389 9,695 * 92.4 N/A N/A
Reader Creek 388 11,353 * 100.7 N/A N/A
Reader Creek C 12,391 * 103.1 N/A N/A
Reader Creek 387 13,577 * 108.4 N/A N/A
Reader Creek 386 15,329 * 119.1 N/A N/A
Reader Creek D 16,215 * 122.8 N/A N/A
Reader Creek 384 17,243 * 131.0 N/A N/A
Reader Creek 383 17,851 * 138.2 N/A N/A
Reader Creek 279 18,329 * 144.4 N/A N/A
Reader Creek 278 18,416 * 152.7 N/A N/A
Reader Creek 277 18,677 * 152.7 N/A N/A
Reader Creek E 19,143 * 152.7 N/A N/A
Rocky Creek A 10,460 * 14.0 N/A N/A
Rocky Creek 410 10,951 * 16.1 N/A N/A
Rocky Creek 409 11,566 * 18.2 N/A N/A
Rocky Creek B 12,663 * 20.5 N/A N/A
Rocky Creek 408 13,678 * 23.9 N/A N/A
Rocky Creek 407 14,161 * 27.1 N/A N/A
Rocky Creek 406 14,538 * 28.7 N/A N/A
Rocky Creek C 14,770 * 48.4 N/A N/A
Rocky Creek 404 15,201 * 48.4 N/A N/A
Rocky Creek 403 15,794 * 48.4 N/A N/A
Rocky Creek 402 17,157 * 48.4 N/A N/A
Rocky Creek D 17,378 * 62.9 N/A N/A Unnamed Tributary to Beale Creek
99 568 * 20.3 N/A N/A
Unnamed Tributary to Beale Creek
A 1,083 * 25.2 N/A N/A
108
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right Unnamed Tributary to Beale Creek
97 2,340 * 36.8 N/A N/A
Unnamed Tributary to Beale Creek
B 3,464 * 40.1 N/A N/A
Unnamed Tributary to Beale Creek
C 5,063 * 46.2 N/A N/A
Unnamed Tributary to Bray Mill Creek
883 78 * 68.7 N/A N/A
Unnamed Tributary to Bray Mill Creek
740 266 * 70.7 N/A N/A
Unnamed Tributary to Bray Mill Creek
739 455 * 73.1 N/A N/A
Unnamed Tributary to Bray Mill Creek
738 644 * 75.7 N/A N/A
Unnamed Tributary to Bray Mill Creek
737 1,750 * 85.2 N/A N/A
Unnamed Tributary to Bray Mill Creek
736 2,784 * 99.7 N/A N/A
Unnamed Tributary to Bray Mill Creek
735 3,808 * 121.1 N/A N/A
Unnamed Tributary to Bray Mill Creek
734 4,823 * 138.4 N/A N/A
Unnamed Tributary to Bray Mill Creek
733 5,660 * 159.1 N/A N/A
Unnamed Tributary to Bray Mill Creek
732 7,203 * 177.0 N/A N/A
Unnamed Tributary to Bray Mill Creek
731 8,693 * 205.9 N/A N/A
Unnamed Tributary to Bray Mill Creek
730 9,993 * 246.2 N/A N/A
109
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right Unnamed Tributary to Escambia River
708 2,360 * 52.7 N/A N/A
Unnamed Tributary to Escambia River
882 2,997 * 53.9 N/A N/A
Unnamed Tributary to Escambia River
707 3,404 * 56.0 N/A N/A
Unnamed Tributary to Escambia River
706 4,356 * 63.0 N/A N/A
Unnamed Tributary to Escambia River
705 4,839 * 67.9 N/A N/A
Unnamed Tributary to Escambia River
704 5,682 * 73.8 N/A N/A
Unnamed Tributary to Escambia River
703 6,779 * 80.6 N/A N/A
Unnamed Tributary to Escambia River
702 7,460 * 84.4 N/A N/A
Unnamed Tributary to Escambia River
701 8,371 * 89.7 N/A N/A
Unnamed Tributary to Escambia River
700 9,411 * 100.3 N/A N/A
Unnamed Tributary to Escambia River
699 10,418 * 105.9 N/A N/A
Unnamed Tributary to Escambia River
698 11,437 * 118.1 N/A N/A
Unnamed Tributary to Escambia River
697 12,324 * 135.0 N/A N/A
Unnamed Tributary to Escambia River
696 13,223 * 146.9 N/A N/A
Unnamed Tributary to Escambia River
695 13,741 * 155.7 N/A N/A
110
Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right West Fork Big Coldwater Creek 412 2,724 * 51.2 N/A N/A
West Fork Big Coldwater Creek F 5,001 * 51.4 N/A N/A
West Fork Big Coldwater Creek 436 5,952 * 51.7 N/A N/A
West Fork Big Coldwater Creek 457 6,848 * 52.0 N/A N/A
West Fork Big Coldwater Creek 456 7,778 * 52.5 N/A N/A
West Fork Big Coldwater Creek 455 8,929 * 53.0 N/A N/A
West Fork Big Coldwater Creek 454 10,388 * 54.1 N/A N/A
West Fork Big Coldwater Creek 453 10,893 * 54.5 N/A N/A
West Fork Big Coldwater Creek G 11,148 * 55.0 N/A N/A
West Fork Big Coldwater Creek 451 11,396 * 55.4 N/A N/A
West Fork Big Coldwater Creek 450 11,879 * 55.5 N/A N/A
West Fork Big Coldwater Creek 449 12,901 * 55.6 N/A N/A
West Fork Big Coldwater Creek 435 13,883 * 56.0 N/A N/A
West Fork Big Coldwater Creek 448 14,846 * 56.8 N/A N/A
West Fork Big Coldwater Creek 447 15,883 * 57.5 N/A N/A
West Fork Big Coldwater Creek H 16,903 * 57.8 N/A N/A
West Fork Big Coldwater Creek 445 17,912 * 58.1 N/A N/A
West Fork Big Coldwater Creek 444 18,946 * 58.9 N/A N/A
West Fork Big Coldwater Creek 443 19,957 * 59.6 N/A N/A
West Fork Big Coldwater Creek 442 21,013 * 60.0 N/A N/A
West Fork Big Coldwater Creek I 21,857 * 60.7 N/A N/A
West Fork Big Coldwater Creek 440 23,098 * 61.6 N/A N/A
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Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right West Fork Big Coldwater Creek 439 23,888 * 62.1 N/A N/A
West Fork Big Coldwater Creek 438 24,731 * 62.7 N/A N/A
West Fork Big Coldwater Creek 434 25,730 * 63.1 N/A N/A
West Fork Big Coldwater Creek J 26,724 * 63.4 N/A N/A
West Fork Big Coldwater Creek 432 27,602 * 63.8 N/A N/A
West Fork Big Coldwater Creek 431 28,583 * 64.3 N/A N/A
West Fork Big Coldwater Creek 430 29,618 * 64.6 N/A N/A
West Fork Big Coldwater Creek 429 30,634 * 65.2 N/A N/A
West Fork Big Coldwater Creek 428 31,694 * 65.7 N/A N/A
West Fork Big Coldwater Creek K 32,691 * 66.4 N/A N/A
West Fork Big Coldwater Creek 426 33,854 * 67.5 N/A N/A
West Fork Big Coldwater Creek 425 34,683 * 68.1 N/A N/A
West Fork Big Coldwater Creek 424 35,687 * 69.0 N/A N/A
West Fork Big Coldwater Creek 423 36,429 * 70.1 N/A N/A
West Fork Big Coldwater Creek 422 37,135 * 70.8 N/A N/A
West Fork Big Coldwater Creek L 38,695 * 71.8 N/A N/A
West Fork Big Coldwater Creek 420 39,705 * 72.8 N/A N/A
West Fork Big Coldwater Creek 419 40,641 * 74.0 N/A N/A
West Fork Big Coldwater Creek 418 41,284 * 74.8 N/A N/A
West Fork Big Coldwater Creek 417 42,534 * 76.2 N/A N/A
West Fork Big Coldwater Creek M 43,558 * 77.5 N/A N/A
West Fork Big Coldwater Creek 415 44,310 * 78.3 N/A N/A
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Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right West Fork Big Coldwater Creek 414 45,315 * 79.0 N/A N/A
West Fork Big Coldwater Creek 413 46,323 * 79.9 N/A N/A
West Fork Big Coldwater Creek 437 47,204 * 80.7 N/A N/A
West Fork Big Coldwater Creek 463 47,647 * 81.1 N/A N/A
West Fork Big Coldwater Creek 462 47,947 * 81.6 N/A N/A
West Fork Big Coldwater Creek N 48,085 * 84.0 N/A N/A
West Fork Big Coldwater Creek 460 48,538 * 84.1 N/A N/A
West Fork Big Coldwater Creek 459 49,617 * 84.3 N/A N/A
West Fork Big Coldwater Creek O 50,487 * 84.4 N/A N/A
West Fork Big Coldwater Creek 824 51,067 * 84.5 N/A N/A
West Fork Big Coldwater Creek 823 51,765 * 84.5 N/A N/A
West Fork Big Coldwater Creek 822 52,450 * 84.7 N/A N/A
West Fork Big Coldwater Creek 821 53,430 * 85.2 N/A N/A
West Fork Big Coldwater Creek 820 54,395 * 85.6 N/A N/A
West Fork Big Coldwater Creek 819 55,132 * 86.0 N/A N/A
West Fork Big Coldwater Creek 818 55,681 * 87.1 N/A N/A
West Fork Big Coldwater Creek 817 55,718 * 87.6 N/A N/A
West Fork Big Coldwater Creek 816 56,414 * 88.4 N/A N/A
West Fork Big Coldwater Creek 815 57,453 * 88.8 N/A N/A
West Fork Big Coldwater Creek 814 58,256 * 89.0 N/A N/A
West Fork Big Coldwater Creek 813 59,109 * 89.3 N/A N/A
West Fork Big Coldwater Creek 812 60,259 * 89.3 N/A N/A
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Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right West Fork Big Coldwater Creek 811 61,187 * 89.4 N/A N/A
West Fork Big Coldwater Creek 796 62,257 * 90.8 N/A N/A
West Fork Big Coldwater Creek 810 63,137 * 92.4 N/A N/A
West Fork Big Coldwater Creek 795 63,966 * 93.6 N/A N/A
West Fork Big Coldwater Creek 809 65,177 * 94.3 N/A N/A
West Fork Big Coldwater Creek 808 66,144 * 95.0 N/A N/A
West Fork Big Coldwater Creek 794 67,075 * 95.2 N/A N/A
West Fork Big Coldwater Creek 807 67,941 * 95.6 N/A N/A
West Fork Big Coldwater Creek 806 68,713 * 96.0 N/A N/A
West Fork Big Coldwater Creek 793 69,790 * 96.7 N/A N/A
West Fork Big Coldwater Creek 792 70,797 * 97.3 N/A N/A
West Fork Big Coldwater Creek 791 72,228 * 98.4 N/A N/A
West Fork Big Coldwater Creek 790 72,691 * 98.9 N/A N/A
West Fork Big Coldwater Creek 789 73,671 * 99.6 N/A N/A
West Fork Big Coldwater Creek 788 74,704 * 100.7 N/A N/A
West Fork Big Coldwater Creek 787 75,508 * 101.6 N/A N/A
West Fork Big Coldwater Creek 786 76,394 * 102.4 N/A N/A
West Fork Big Coldwater Creek 785 77,196 * 103.3 N/A N/A
West Fork Big Coldwater Creek 805 78,139 * 104.5 N/A N/A
West Fork Big Coldwater Creek 784 79,178 * 105.6 N/A N/A
West Fork Big Coldwater Creek 783 79,983 * 106.2 N/A N/A
West Fork Big Coldwater Creek 782 80,292 * 106.7 N/A N/A
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Table 25: Flood Hazard and Non-Encroachment Data for Selected Streams
Flooding Source Cross
Section Stream Station1
1% Annual Chance Flood
Discharge (cfs)
1% Annual Chance Water
Surface Elevation
(feet NAVD88)
Non-Encroachment
Width (feet)
Left Right West Fork Big Coldwater Creek 781 80,474 * 107.1 N/A N/A
West Fork Big Coldwater Creek 804 80,553 * 108.0 N/A N/A
West Fork Big Coldwater Creek 803 81,136 * 109.0 N/A N/A
West Fork Big Coldwater Creek 802 82,636 * 109.6 N/A N/A
West Fork Big Coldwater Creek 801 83,866 * 109.9 N/A N/A
West Fork Big Coldwater Creek 800 85,060 * 110.4 N/A N/A
West Fork Big Coldwater Creek 799 86,244 * 112.1 N/A N/A
West Fork Big Coldwater Creek 798 87,241 * 114.0 N/A N/A
West Fork Big Coldwater Creek 797 88,164 * 114.9 N/A N/A
1 Feet above mouth *Not calculated for this Flood Risk Project
6.4 Coastal Flood Hazard Mapping Flood insurance zones and BFEs including the wave effects were identified on each transect based on the results from the onshore wave hazard analyses. Between transects, elevations were interpolated using topographic maps, land-use and land-cover data, and knowledge of coastal flood processes to determine the aerial extent of flooding. Sources for topographic data are shown in Table 23. Zone VE is subdivided into elevation zones and BFEs are provided on the FIRM. The limit of Zone VE shown on the FIRM is defined as the farthest inland extent of any of these criteria (determined for the 1% annual chance flood condition):
• The primary frontal dune zone is defined in 44 CFR Section 59.1 of the NFIP regulations. The primary frontal dune represents a continuous or nearly continuous mound or ridge of sand with relatively steep seaward and landward slopes that occur immediately landward and adjacent to the beach. The primary frontal dune zone is subject to erosion and overtopping from high tides and waves during major coastal storms. The inland limit of the primary frontal dune zone occurs at the point where there is a distinct change from a
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relatively steep slope to a relatively mild slope.
• The wave runup zone occurs where the (eroded) ground profile is 3.0 feet or more below the 2-percent wave runup elevation.
• The wave overtopping splash zone is the area landward of the crest of an overtopped
barrier, in cases where the potential 2-percent wave runup exceeds the barrier crest elevation by 3.0 feet or more.
• The breaking wave height zone occurs where 3-foot or greater wave heights could occur
(this is the area where the wave crest profile is 2.1 feet or more above the total stillwater elevation).
• The high-velocity flow zone is landward of the overtopping splash zone (or area on a
sloping beach or other shore type), where the product of depth of flow times the flow velocity squared (hv2) is greater than or equal to 200 ft3/sec2. This zone may only be used on the Pacific Coast.
The SFHA boundary indicates the limit of SFHAs shown on the FIRM as either “V” zones or “A” zones. Table 26 indicates the coastal analyses used for floodplain mapping and the criteria used to determine the inland limit of the open-coast Zone VE and the SFHA boundary at each transect.
Table 26: Summary of Coastal Transect Mapping Considerations
Coastal Transect
Primary Frontal
Dune (PFD) Identified
Wave Runup Analysis
Wave Height Analysis
Zone VE Limit
SFHA Boundary
Zone Designation
and BFE (ft NAVD 88)
Zone Designation
and BFE (ft NAVD 88)
1 YES N/A VE 11-14 AE 8-11 PFD WHAFIS
2 YES N/A VE 12-15 AE 8-12 PFD PFD &
WHAFIS
3 NO N/A VE 13-16 AE 10-13 WHAFIS WHAFIS
4 NO N/A VE 14-17 AE 11-14 WHAFIS WHAFIS
5 NO N/A VE 14-17 AE 12-14 WHAFIS WHAFIS
6 NO N/A VE 13-16 AE 11-13 WHAFIS WHAFIS
7 NO N/A VE 13-15 AE 10-13 WHAFIS WHAFIS
8 NO N/A VE 12-15 AE 9-12 WHAFIS WHAFIS
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Table 26: Summary of Coastal Transect Mapping Considerations
Coastal Transect
Primary Frontal
Dune (PFD) Identified
Wave Runup Analysis
Wave Height Analysis
Zone VE Limit
SFHA Boundary
Zone Designation
and BFE (ft NAVD 88)
Zone Designation
and BFE (ft NAVD 88)
9 NO N/A VE 12-14 AE 9-12 WHAFIS WHAFIS
10 NO N/A VE 11-13 AE 8-11 WHAFIS WHAFIS
11 NO N/A VE 11-13 AE 8-11 WHAFIS WHAFIS
12 NO N/A VE 10-12 AE 7-10 WHAFIS WHAFIS
13 NO N/A VE 10-11 AE 6-10 WHAFIS WHAFIS
14 NO N/A VE 10-13 AE 8-10 WHAFIS WHAFIS
15 NO N/A VE 11-13 AE 8-11 WHAFIS WHAFIS
16 NO N/A VE 11-14 AE 8-11 WHAFIS WHAFIS
17 NO N/A VE 11-14 AE 9-11 WHAFIS WHAFIS
18 NO N/A VE 12-14 AE 9-12 WHAFIS WHAFIS
19 NO N/A VE 12-13 AE 9-12 WHAFIS WHAFIS
20 NO N/A VE 12-13 AE 8-12 WHAFIS WHAFIS
21 NO N/A VE 11-13 AE 7-12 WHAFIS WHAFIS
22 NO N/A VE 11-13 AE 9-11 WHAFIS WHAFIS
23 NO N/A VE 11-12 AE 8-11 WHAFIS WHAFIS
24 NO N/A VE 11-13 AE 8-11 WHAFIS WHAFIS
25 NO N/A VE 11-13 AE 8-11 WHAFIS WHAFIS
26 NO N/A VE 11-12 AE 8-11 WHAFIS WHAFIS
27 NO N/A VE 11-12 AE 7-11 WHAFIS WHAFIS
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Table 26: Summary of Coastal Transect Mapping Considerations
Coastal Transect
Primary Frontal
Dune (PFD) Identified
Wave Runup Analysis
Wave Height Analysis
Zone VE Limit
SFHA Boundary
Zone Designation
and BFE (ft NAVD 88)
Zone Designation
and BFE (ft NAVD 88)
28 NO N/A VE 10-13 AE 8-11 WHAFIS WHAFIS
29 NO N/A VE 10-12 AE 8-10 WHAFIS WHAFIS
30 NO N/A VE 10-11 AE 7-10 WHAFIS WHAFIS
31 NO N/A VE 10-11 AE 8-10 WHAFIS WHAFIS
32 NO N/A VE 10-11 AE 8-10 WHAFIS WHAFIS
33 NO VE 10 VE 10-11 AE 8-10 WHAFIS RUNUP
34 NO VE 11 VE 10-11 AE 7-10 RUNUP RUNUP
35 NO VE 11 VE 10 AE 8-10 RUNUP RUNUP
36 NO AE 10 VE 9-10 AE 6-9 RUNUP RUNUP
37 NO N/A VE 9-11 AE 7-9 WHAFIS WHAFIS
38 NO AE 9 VE 9-11 AE 7-9 WHAFIS RUNUP
39 NO VE 13 VE 9-11 AE 7-9 RUNUP RUNUP
40 NO VE 11 VE 10-11 AE 7-10 RUNUP
RUNUP & OVERTOPPI
NG
41 NO N/A VE 10-12 AE 8-10 WHAFIS WHAFIS
42 NO N/A VE 10-12 AE 8-10 WHAFIS WHAFIS
43 NO VE 12 VE 10-12 AE 8-10 RUNUP RUNUP
44 NO N/A VE 10-12 AE 8-10 WHAFIS WHAFIS
45 NO N/A VE 10-12 AE 8-10 WHAFIS WHAFIS
46 NO N/A VE 10-12 AE 6-10 WHAFIS WHAFIS
47 NO N/A VE 10-12 AE 7-10 WHAFIS WHAFIS
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Table 26: Summary of Coastal Transect Mapping Considerations
Coastal Transect
Primary Frontal
Dune (PFD) Identified
Wave Runup Analysis
Wave Height Analysis
Zone VE Limit
SFHA Boundary
Zone Designation
and BFE (ft NAVD 88)
Zone Designation
and BFE (ft NAVD 88)
48 NO N/A VE 10-12 AE 7-10 WHAFIS WHAFIS
49 NO N/A VE 10-12 AE 7-10 WHAFIS WHAFIS
50 NO N/A VE 10-12 AE 7-10 WHAFIS WHAFIS
51 NO N/A VE 10-11 AE 8-10 WHAFIS WHAFIS
52 NO N/A VE 10-12 AE 7-10 WHAFIS WHAFIS
53 NO N/A VE 10-12 AE 8-10 WHAFIS WHAFIS
55 NO N/A VE 11-12 AE 8-11 WHAFIS WHAFIS
56 NO N/A VE 11-12 AE 9-11 WHAFIS WHAFIS
57 NO N/A VE 11-12 AE 8-11 WHAFIS WHAFIS
58 NO N/A VE 11-12 AE 9-11 WHAFIS WHAFIS
59 NO N/A VE 11-12 AE 9-11 WHAFIS WHAFIS
60 NO N/A VE 11-12 AE 9-11 WHAFIS WHAFIS
61 NO N/A VE 11-12 AE 9-11 WHAFIS WHAFIS
62 NO N/A VE 11-13 AE 9-11 WHAFIS WHAFIS
63 NO VE 15 VE 11-13 AE 9-11 RUNUP RUNUP
64 NO N/A VE 11-13 AE 9-11 WHAFIS WHAFIS
A LiMWA boundary has also been added in coastal areas subject to wave action for use by local communities in safe rebuilding practices. The LiMWA represents the approximate landward limit of the 1.5-foot breaking wave. To simplify representation, the LiMWA was continued immediately landward of the VE/AE boundary in areas where wave runup elevations dominate. Similarly, in areas where the Zone VE designation is based on the presence of a primary frontal dune or wave overtopping, the LiMWA was delineated immediately landward of the Zone VE/AE boundary.
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6.5 FIRM Revisions This FIS Report and the FIRM are based on the most up-to-date information available to FEMA at the time of its publication; however, flood hazard conditions change over time. Communities or private parties may request flood map revisions at any time. Certain types of requests require submission of supporting data. FEMA may also initiate a revision. Revisions may take several forms, including Letters of Map Amendment (LOMAs), Letters of Map Revision Based on Fill (LOMR-Fs), Letters of Map Revision (LOMRs) (referred to collectively as Letters of Map Change (LOMCs)), Physical Map Revisions (PMRs), and FEMA-contracted restudies. These types of revisions are further described below. Some of these types of revisions do not result in the republishing of the FIS Report. To assure that any user is aware of all revisions, it is advisable to contact the community repository of flood-hazard data (shown in Table 31, “Map Repositories”).
6.5.1 Letters of Map Amendment A LOMA is an official revision by letter to an effective NFIP map. A LOMA results from an administrative process that involves the review of scientific or technical data submitted by the owner or lessee of property who believes the property has incorrectly been included in a designated SFHA. A LOMA amends the currently effective FEMA map and establishes that a specific property is not located in a SFHA. A LOMA cannot be issued for properties located on the PFD (primary frontal dune). To obtain an application for a LOMA, visit www.fema.gov/floodplain-management/letter-map-amendment-loma and download the form “MT-1 Application Forms and Instructions for Conditional and Final Letters of Map Amendment and Letters of Map Revision Based on Fill”. Visit the “Flood Map-Related Fees” section to determine the cost, if any, of applying for a LOMA. FEMA offers a tutorial on how to apply for a LOMA. The LOMA Tutorial Series can be accessed at www.fema.gov/online-tutorials.
For more information about how to apply for a LOMA, call the FEMA Map Information eXchange; toll free, at 1-877-FEMA MAP (1-877-336-2627).
6.5.2 Letters of Map Revision Based on Fill A LOMR-F is an official revision by letter to an effective NFIP map. A LOMR-F states FEMA’s determination concerning whether a structure or parcel has been elevated on fill above the base flood elevation and is, therefore, excluded from the SFHA. Information about obtaining an application for a LOMR-F can be obtained in the same manner as that for a LOMA, by visiting www.fema.gov/floodplain-management/letter-map-amendment-loma for the “MT-1 Application Forms and Instructions for Conditional and Final Letters of Map Amendment and Letters of Map Revision Based on Fill” or by calling the FEMA Map Information eXchange, toll free, at 1-877-FEMA MAP (1-877-336-2627). Fees for applying for a LOMR-F, if any, are listed in the “Flood Map-Related Fees” section. A tutorial for LOMR-F is available at www.fema.gov/online-tutorials.
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6.5.3 Letters of Map Revision A LOMR is an official revision to the currently effective FEMA map. It is used to change flood zones, floodplain and floodway delineations, flood elevations and planimetric features. All requests for LOMRs should be made to FEMA through the chief executive officer of the community, since it is the community that must adopt any changes and revisions to the map. If the request for a LOMR is not submitted through the chief executive officer of the community, evidence must be submitted that the community has been notified of the request. To obtain an application for a LOMR, visit www.fema.gov/national-flood-insurance-program-flood-hazard-mapping/mt-2-application-forms-and-instructions and download the form “MT-2 Application Forms and Instructions for Conditional Letters of Map Revision and Letters of Map Revision”. Visit the “Flood Map-Related Fees” section to determine the cost of applying for a LOMR. For more information about how to apply for a LOMR, call the FEMA Map Information eXchange; toll free, at 1-877-FEMA MAP (1-877-336-2627) to speak to a Map Specialist. Previously issued mappable LOMCs (including LOMRs) that have been incorporated into the Santa Rosa County FIRM are listed in Table 27.
Table 27: Incorporated Letters of Map Change (Not Applicable to this Flood Risk Project)
6.5.4 Physical Map Revisions A PMR is Physical Map Revisions (PMRs) are an official republication of a community’s NFIP map to effect changes to base flood elevations, floodplain boundary delineations, regulatory floodways and planimetric features. These changes typically occur as a result of structural works or improvements, annexations resulting in additional flood hazard areas or correction to base flood elevations or SFHAs. The community’s chief executive officer must submit scientific and technical data to FEMA to support the request for a PMR. The data will be analyzed and the map will be revised if warranted. The community is provided with copies of the revised information and is afforded a review period. When the base flood elevations are changed, a 90-day appeal period is provided. A 6-month adoption period for formal approval of the revised map(s) is also provided. For more information about the PMR process, please visit www.fema.gov and visit the “Flood Map Revision Processes” section.
6.5.5 Contracted Restudies The NFIP provides for a periodic review and restudy of flood hazards within a given community. FEMA accomplishes this through a national watershed-based mapping needs assessment strategy, known as the Coordinated Needs Management Strategy (CNMS). The CNMS is used by FEMA to assign priorities and allocate funding for new flood hazard analyses used to update the FIS Report and FIRM. The goal of CNMS is to define the validity of the engineering study data within a mapped inventory. The CNMS is used to track the assessment process, document engineering gaps and their resolution, and aid in prioritization for using flood risk as a key factor for areas identified for flood map updates. Visit www.fema.gov to learn more about the CNMS or contact the FEMA Regional Office listed in Section 8 of this FIS Report.
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6.5.6 Community Map History The current FIRM presents flooding information for the entire geographic area of Santa Rosa County. Previously, separate FIRMs, Flood Hazard Boundary Maps (FHBMs) and/or Flood Boundary and Floodway Maps (FBFMs) may have been prepared for the incorporated communities and the unincorporated areas in the county that had identified SFHAs. Current and historical data relating to the maps prepared for the project area are presented in Table 28, “Community Map History.” A description of each of the column headings and the source of the date is also listed below.
• Community Name includes communities falling within the geographic area shown on the FIRM, including those that fall on the boundary line, nonparticipating communities, and communities with maps that have been rescinded. Communities with No Special Flood Hazards are indicated by a footnote. If all maps (FHBM, FBFM, and FIRM) were rescinded for a community, it is not listed in this table unless SFHAs have been identified in this community.
• Initial Identification Date (First NFIP Map Published) is the date of the first NFIP map
that identified flood hazards in the community. If the FHBM has been converted to a FIRM, the initial FHBM date is shown. If the community has never been mapped, the upcoming effective date or “pending” (for Preliminary FIS Reports) is shown. If the community is listed in Table 28 but not identified on the map, the community is treated as if it were unmapped.
• Initial FHBM Effective Date is the effective date of the first Flood Hazard Boundary Map
(FHBM). This date may be the same date as the Initial NFIP Map Date.
• FHBM Revision Date(s) is the date(s) that the FHBM was revised, if applicable.
• Initial FIRM Effective Date is the date of the first effective FIRM for the community.
• FIRM Revision Date(s) is the date(s) the FIRM was revised, if applicable. This is the revised date that is shown on the FIRM panel, if applicable. As countywide studies are completed or revised, each community listed should have its FIRM dates updated accordingly to reflect the date of the countywide study. Once the FIRMs exist in countywide format, as Physical Map Revisions (PMR) of FIRM panels within the county are completed, the FIRM Revision Dates in the table for each community affected by the PMR are updated with the date of the PMR, even if the PMR did not revise all the panels within that community.
The initial effective date for the Santa Rosa County FIRMs in countywide format was 12/19/2006.
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Table 28: Community Map History
Community Name
Initial Identification
Date
Initial FHBM
Effective Date
FHBM Revision Date(s)
Initial FIRM Effective
Date
FIRM Revision Date(s)
Gulf Breeze, City of 06/28/1974 06/28/1974 01/30/1976 09/01/1977
12/19/2006 01/19/2000 06/16/1995 08/03/1992 11/01/1985
Jay, Town of 10/10/1975 10/10/1975 N/A 05/15/1986 12/19/2006
Milton, City of 05/24/1974 05/24/1974 N/A 06/01/1977 12/19/2006 07/18/1985
Santa Rosa, Unincorporated Areas 01/24/1975 01/24/1975 N/A 10/14/1977
12/19/2006 07/17/2002 01/19/2000 07/20/1998 08/03/1992 11/01/1985
SECTION 7.0 – CONTRACTED STUDIES AND COMMUNITY COORDINATION
7.1 Contracted Studies Table 29 provides a summary of the contracted studies, by flooding source, which are included in this FIS Report.
Table 29: Summary of Contracted Studies Included in this FIS Report
Flooding Source
FIS Report Dated
Contractor Number Work
Completed Date
Affected Communities
Beale Creek TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Big Coldwater Creek TBD AECOM EMA-2009-CA-
5937 2018 Santa Rosa County, Unincorporated Areas
Blackwater Bay TBD AECOM EMA-2009-CA-
5937 2015 Santa Rosa County, Unincorporated Areas
Blackwater River TBD NWFWMD EMA-2009-CA-
5937 2012 City of Milton, Santa Rosa County, Unincorporated Areas
Bray Mill Creek TBD AECOM EMA-2009-CA-
5937 2012 Santa Rosa County, Unincorporated Areas, Town of Jay
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Flooding Source
FIS Report Dated
Contractor Number Work
Completed Date
Affected Communities
Clear Creek TBD AECOM EMA-2009-CA-5937 2018 Santa Rosa County,
Unincorporated Areas
Clear Creek TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
East Bay TBD AECOM EMA-2009-CA-5937 2015 Santa Rosa County,
Unincorporated Areas
East Bay River 11/01/85
Stottler Stagg & Associates and GKY & A ssociates, Inc
EMW-C-0969 1984 Santa Rosa County, Unincorporated Areas
East Fork Big Coldwater Creek
TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Escambia Bay TBD AECOM EMA-2009-CA-5937 2015 Santa Rosa County,
Unincorporated Areas
Escambia River 11/01/85
Stottler Stagg & Associates and GKY & A ssociates, Inc
EMW-C-0969 1984 Santa Rosa County, Unincorporated Areas
Gulf of Mexico TBD AECOM EMA-2009-CA-5937 2015 Santa Rosa County,
Unincorporated Areas
Holley by the Sea TBD AECOM EMA-2009-CA-
5937 2016 Santa Rosa County, Unincorporated Areas
Jacobs Creek TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Juniper Creek TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Long Branch TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Malloy Branch TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Manning Creek TBD AECOM EMA-2009-CA-
5937 2012 Santa Rosa County, Unincorporated Areas
Pace Mill Creek 12/19/06 Dewberry &
Davis LLC N/A 2005 Santa Rosa County, Unincorporated Areas
Pensacola Bay TBD AECOM EMA-2009-CA-
5937 2015 City of Gulf Breeze, Santa Rosa County, Unincorporated Areas
Pond Creek TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
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Flooding Source
FIS Report Dated
Contractor Number Work
Completed Date
Affected Communities
Pond Creek 12/19/06 Dewberry & Davis LLC N/A 2005
City of Milton, Santa Rosa County, Unincorporated Areas
Reader Creek TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Rocky Creek TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Santa Rosa Sound TBD AECOM EMA-2009-CA-
5937 2015 City of Gulf Breeze, Santa Rosa County, Unincorporated Areas
Unnamed Tributary to Beale Creek
TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Unnamed Tributary to Bray Mill Creek
TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Unnamed Tributary to Escambia River
TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
West Fork Big Coldwater Creek
TBD AECOM EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
Yellow River TBD NWFWMD EMA-2009-CA-5937 2012 Santa Rosa County,
Unincorporated Areas
7.2 Community Meetings The dates of the community meetings held for this Flood Risk Project and previous Flood Risk Projects are shown in Table 30. These meetings may have previously been referred to by a variety of names (Community Coordination Officer (CCO), Scoping, Discovery, etc.), but all meetings represent opportunities for FEMA, community officials, study contractors, and other invited guests to discuss the planning for and results of the project.
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Table 30: Community Meetings
Community FIS Report Dated Date of Meeting Meeting Type Attended By
Gulf Breeze, City of
November 1, 1985 August 8, 1979 Initial CCO FEMA, the community, and the study contractor
December 4, 1984 Final CCO FEMA, the community, and the study contractor
January 19, 2000 July 14, 1998 Initial CCO FEMA, the community, and the study contractor
February 12, 1999 Final CCO FEMA, the community, and the study contractor
Milton, City of
May 15, 1985 August 8, 1979 Initial CCO FEMA, the community, and the study contractor
December 5, 1984 Final CCO FEMA, the community, and the study contractor
December 19, 2006 Initial CCO None Held
November 10, 2005 Final CCO FEMA, NWFWMD, the Town of Jay, Santa Rosa County, and the State of Florida
Santa Rosa County and Incorporated Areas
December 19, 2006 December 19, 2006 Initial CCO None Held
Final CCO FEMA, NWFWMD, the Town of Jay, Santa Rosa County, and the State of Florida
Santa Rosa County (Unincorporated Areas)
November 1, 1985 August 8, 1979 Initial CCO FEMA, the community, and the study contractor
December 5, 1984 Final CCO FEMA, the community, and the study contractor
January 19, 2000 July 14, 1997 Initial CCO FEMA, the community, and the study contractor
February 12, 1999 Final CCO FEMA, the community, and the study contractor
July 17, 2002 June 12, 2001 Initial CCO FEMA, the community, and the study contractor
Final CCO None Held
July 18, 2016 Initial CCO
Final CCO
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SECTION 8.0 – ADDITIONAL INFORMATION
Information concerning the pertinent data used in the preparation of this FIS Report can be obtained by submitting an order with any required payment to the FEMA Engineering Library. For more information on this process, see www.fema.gov. Table 31 is a list of the locations where FIRMs for Santa Rosa County can be viewed. Please note that the maps at these locations are for reference only and are not for distribution. Also, please note that only the maps for the community listed in the table are available at that particular repository. A user may need to visit another repository to view maps from an adjacent community.
Table 31: Map Repositories
Community Address City State Zip Code
Gulf Breeze, City of City Hall
1070 Shoreline Drive Gulf Breeze FL 32561
Jay, Town of Town Hall
3695 Highway 4 Jay FL 32565
Milton, City of Planning and Development
Department 6738 Dixon Street
Milton FL 32572
Santa Rosa County (Unincorporated Areas)
Santa Rosa County Public Services Department
6051 Old Bagdad Highway Milton FL 32583
The National Flood Hazard Layer (NFHL) dataset is a compilation of effective FIRM databases and LOMCs. Together they create a GIS data layer for a State or Territory. The NFHL is updated as studies become effective and extracts are made available to the public monthly. NFHL data can be viewed or ordered from the website shown in Table 32. Table 32 contains useful contact information regarding the FIS Report, the FIRM, and other relevant flood hazard and GIS data. In addition, information about the State NFIP Coordinator and GIS Coordinator is shown in this table. At the request of FEMA, each Governor has designated an agency of State or territorial government to coordinate that State's or territory's NFIP activities. These agencies often assist communities in developing and adopting necessary floodplain management measures. State GIS Coordinators are knowledgeable about the availability and location of State and local GIS data in their state.
127
Table 32: Additional Information
FEMA and the NFIP
FEMA and FEMA Engineering Library website
www.fema.gov/national-flood-insurance-program-flood-hazard-mapping/engineering-library
NFIP website www.fema.gov/national-flood-insurance-program
NFHL Dataset msc.fema.gov
FEMA Region IV Federal Emergency Management Agency 3003 Chamblee Tucker Road Atlanta, GA 30341 (770) 220-5200
Other Federal Agencies
USGS website www.usgs.gov
Hydraulic Engineering Center website
www.hec.usace.army.mil
State Agencies and Organizations
State NFIP Coordinator Steve Martin, CFM Florida Division of Emergency Management 2555 Shumard Oak Boulevard Tallahassee, FL 32399 850-922-5269 [email protected]
State GIS Coordinator Richard Butgereit, GIS Administer Florida Division of Emergency Management 2555 Shumard Oak Boulevard Tallahassee, FL 32399 850-413-9907 [email protected]
SECTION 9.0 – BIBLIOGRAPHY AND REFERENCES
Table 33 includes sources used in the preparation of and cited in this FIS Report as well as additional studies that have been conducted in the study area.
128
Table 33: Bibliography and References
Citation in this FIS
Publisher/ Issuer
Publication Title, “Article,” Volume, Number, etc. Author/Editor Place of
Publication
Publication Date/
Date of Issuance
Link
BASE1 Santa Rosa County Transportation, Political, Hydrology and Wetland features
Santa Rosa County GIS Milton, FL 09/06/2011 http://www.santarosa.fl.gov/
BASE2 U.G. Geological Survey GIS data
U.S. Geological Survey
Reston, VA 2004 http://www.usgs.gov/
BASE3 Florida Department of Transportation FDOT Imagery
Florida Department of Transportation
Tallahassee, FL 04/18/2013
http://www.dot.state.fl.us/surveyingandmapping/aerialmain.shtm
BASE4 National Geodetic Survey NGS benchmark data
National Oceanic and Atmospheric Administration
Charleston, SC 05/10/2012 http://www.ngs.noaa.gov/
BASE6 US Fish and Wildlife Service National Wetlands Inventory US Fish and
Wildlife Service Falls Church, VA 04/24/2013 www.fws.gov
BASE7 US Census Bureau TIGER Roads US Census Bureau
Washington, D.C 09/13/2011
http://www.census.gov/
FIRM1
Federal Emergency Management Agency
Effective FIRM data for Santa Rosa County, Florida and Incorporated Areas
Federal Emergency Management Agency
Washington, D.C. 12/19/2006 https://msc.fema.gov/portal
FIRM3
Federal Emergency Management Agency
Effective FIRM data for Okaloosa County, Florida and Incorporated Areas
Federal Emergency Management Agency
Washington, D.C. 09/29/2010 https://msc.fema.gov/portal
FIS1
Federal Emergency Management Agency
Santa Rosa County, Florida and Incorporated Areas of Flood Insurance Rate Map
Federal Emergency Management Agency
Washington, D.C. 12/06/2002 http://www.nwfwmd.state.fl.us/
129
Table 33: Bibliography and References
Citation in this FIS
Publisher/ Issuer
Publication Title, “Article,” Volume, Number, etc. Author/Editor Place of
Publication
Publication Date/
Date of Issuance
Link
STUDY1
Federal Emergency Management Agency
FIRM Panel Layout for Santa Rosa County
Federal Emergency Management Agency
Washington, D.C. 07/18/2016 https://msc.fema.gov/portal
STUDY2
Federal Emergency Management Agency
Revised and adjusted effective data for Santa Rosa County
URS Corporation Southern
Tampa, FL 07/18/2016 https://msc.fema.gov/portal
STUDY3
Federal Emergency Management Agency
Modeling data for Santa Rosa County
URS Corporation Southern
Tampa, FL 07/18/2016 https://msc.fema.gov/portal
STUDY4 NWFWMD GIS Department DEM Breakline features
Northwest Florida Water Management District
Havana, FL 2014 http://www.nwfwmd.state.fl.us/
STUDY4
Northwest Florida Water Management District
Modeling data
Federal Emergency Management Agency
Tampa, FL 2016 http://www.nwfwmd.state.fl.us/
STUDY4
Northwest Florida Water Management District GIS Department
DEM
Northwest Florida Water Management District
Havana, FL 2012 http://www.nwfwmd.state.fl.us/
STUDY5
Federal Emergency Management Agency
Modified transition zones URS Corporation Southern
Tampa, FL 07/18/2016 https://msc.fema.gov/portal
130
Table 33: Bibliography and References
Citation in this FIS
Publisher/ Issuer
Publication Title, “Article,” Volume, Number, etc. Author/Editor Place of
Publication
Publication Date/
Date of Issuance
Link
STUDY6
Federal Emergency Management Agency
Detailed coastal analysis using ADCIRC, CHAMP, TWA, CSHORE, and Runup 2.0
Federal Emergency Management Agency
Washington, D.C. 04/01/2014 https://msc.fema.gov/portal
STUDY7
Federal Emergency Management Agency
Modified transition zones using 2 models
URS Corporation Southern
Tampa, FL 07/18/2016 https://msc.fema.gov/portal
STUDY8
Federal Emergency Management Agency
ICPR Modeling for Holley By The Sea Watershed AECOM Tampa, FL 07/18/2016 https://msc.fema.gov/portal
TOPO1
Northwest Florida Water Management District
Santa Rosa Mosaic DEM
Northwest Florida Water Management District
Santa Rosa County 12/31/2009 http://www.nwfwmd.state.fl.us/