Pasco County, Florida and Incorporated Areas
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PASCO COUNTY, FLORIDA AND INCORPORATED AREAS Community Community Name Number DADE CITY, CITY OF 120231 NEW PORT RICHEY, CITY OF 120232 PASCO COUNTY Pasco County 120230 (UNINCORPORTED AREAS) PORT RICHEY, CITY OF 120234 SAN ANTONIO, CITY OF 120634 ST. LEO, TOWN OF 120166 ZEPHYRHILLS, CITY OF 120235 EFFECTIVE: September 26, 2014 Federal Emergency Management Agency FLOOD INSURANCE STUDY NUMBER 12101CV000A NOTICE TO FLOOD INSURANCE STUDY USERS Communities participating in the National Flood Insurance Program have established repositories of flood hazard data for floodplain management and flood insurance purposes. This Flood Insurance Study (FIS) report may not contain all data available within the Community Map Repository. It is advisable to contact the community repository for any additional data. The Federal Emergency Management Agency (FEMA) may revise and republish part or all of this FIS report at any time. In addition, FEMA may revise part of this FIS report by the Letter of Map Revision process, which does not involve republication or redistribution of the FIS report. Therefore, users should consult with community officials and check the Community Map Repository to obtain the most current FIS report components. Selected Flood Insurance Rate Map panels for this community contain information that was previously shown separately on the corresponding Flood Boundary and Floodway Map panels (e.g., floodways, cross sections). In addition, former flood hazard zone designations have been changed as follows: Old Zone(s) New Zone Al through A30 AE V1 through V30 VE B X C X Initial Countywide FIS Effective Date: September 26, 2014 TABLE OF CONTENTS 1.0 INTRODUCTION ................................................................................................................ 1 1.1 Purpose of Study ............................................................................................................. 1 1.2 Authority and Acknowledgments ................................................................................... 1 1.3 Coordination ................................................................................................................... 4 2.0 AREA STUDIED .................................................................................................................. 5 2.1 Scope of Study ................................................................................................................ 5 2.2 Community Description .................................................................................................. 7 2.3 Principal Flood Problems ................................................................................................ 9 2.4 Flood Protection Measures ........................................................................................... 14 3.0 ENGINEERING METHODS ............................................................................................ 15 3.1 Hydrologic Analyses ..................................................................................................... 15 3.1.1 Methods for Flooding Sources Incorporated from Previous Study ..................... 15 3.1.2 Method for Flooding Sources New or Revised Analyses in Current Study ........ 24 3.2 Hydraulic Analyses ....................................................................................................... 26 3.2.1 Methods for Flooding Sources Incoroporated from Previous Study ................... 26 3.2.2 Method for Flooding Sources New or Revised Analyses in Current Study ........ 28 3.3 Wave Height Analysis .................................................................................................. 29 3.4 Vertical Datum .............................................................................................................. 31 4.0 FLOODPLAIN MANAGEMENT APPLICATIONS ..................................................... 32 4.1 Floodplain Boundaries .................................................................................................. 32 4.2 Floodways ..................................................................................................................... 34 4.3 Base Flood Elevations .................................................................................................. 40 4.4 Velocity Zones .............................................................................................................. 40 5.0 INSURANCE APPLICATIONS ....................................................................................... 40 6.0 FLOOD INSURANCE RATE MAP ................................................................................. 42 7.0 OTHER STUDIES .............................................................................................................. 45 8.0 LOCATION OF DATA ...................................................................................................... 45 9.0 BIBLIOGRAPHY AND REFERENCES ......................................................................... 45 i TABLE OF CONTENTS (continued) FIGURES Figure 1 – Transect Schematic .......................................................................................................... 30 Figure 2 – Floodway Schematic ....................................................................................................... 35 TABLES Table 1: Flooding Sources Studied by Detailed Methods ................................................................. 6 Table 2: Letters of Map Change ......................................................................................................... 7 Table 3: Summary of Discharges ............................................................................................................... 18 Table 4: Summary of Stillwater Elevations ...................................................................................... 21 Table 5: Rainfall Values ................................................................................................................... 24 Table 6: Manning’s “n” Values .................................................................................................................. 27 Table 7: Vertical Datum Conversion ................................................................................................ 31 Table 8: Terrain Data for East Pasco Watershed ..................................................................................... 33 Table 9: Floodway Data .................................................................................................................... 36 Table 10: Community Map History .................................................................................................. 44 EXHIBITS Exhibit 1 - Flood Profiles Anclote River Panel 01P Bear Creek Panel 02P Buckhorn Creek Panel 03P Fivemile Creek Panel 04P Hillsborough River Panel 05P Pithlachascotte River Panels 06P-07P Tributary No. 1 Panel 08P Tributary No. 2 Panel 09P Tributary No. 5 Panel 10P Tributary No. 6 Panel 11P Tributary No. 9 Panel 12P Tributary No. 11 Panel 13P Tributary No. 12 Panel 14P Tributary No. 13 Panel 15P Tributary No. 14 Panel 16P Tributary No. 15 Panel 17P Tributary No. 16 Panel 18P Tributary No. 25 Panel 19P Withlacoochee River Panel 20P Exhibit 2 - Flood Insurance Rate Map Index (Published Separately) Flood Insurance Rate Map (Published Separately) ii FLOOD INSURANCE STUDY PASCO COUNTY, FLORIDA AND INCORPORATED AREAS 1.0 INTRODUCTION 1.1 Purpose of Study This Flood Insurance Study (FIS) revises and updates information on the existence and severity of flood hazards in the geographic area of Pasco County, including the Cities of Dade City, New Port Richey, Port Richey, San Antonio, and Zephyrhills; the Town of St. Leo; and the unincorporated areas of Pasco County (referred to collectively herein as Pasco County), and aids in the administration of the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973. This study has developed flood-risk data for various areas of the community that will be used to establish actuarial flood insurance rates and to assist the community in its efforts to promote sound floodplain management. Minimum floodplain management requirements for participation in the National Flood Insurance Program (NFIP) are set forth in the Code of Federal Regulations at 44 CFR, 60.3. In some states or communities, floodplain management criteria or regulations may exist that are more restrictive or comprehensive than the minimum Federal requirements. In such cases, the more restrictive criteria take precedence and the State (or other jurisdictional agency) will be able to explain them. The Digital Flood Insurance Rate Map (DFIRM) and FIS report for this countywide study have been produced in digital format. Flood hazard information was converted to meet the Federal Emergency Management Agency (FEMA) DFIRM database specifications and Geographic Information System (GIS) format requirements. The flood hazard information was created and is provided in a digital format so that it can be incorporated into a local GIS and be accessed more easily by the community. 1.2 Authority and Acknowledgments The sources of authority for this FIS are the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973. Precountywide Analyses Information on the authority and acknowledgements for each jurisdiction included in this countywide FIS, as compiled from their previously printed FIS reports, is shown below: 1 Dade City, City of: The hydrologic and hydraulic