Wilson County, Tennessee, and Incorporated Areas
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WILSON COUNTY, TENNESSEE, AND INCORPORATED AREAS Community Name Community Number LEBANON, CITY OF 470208 MT. JULIET, CITY OF 470290 WATERTOWN, CITY OF 470380 WILSON COUNTY (UNINCORPORATED AREAS) 470207 EFFECTIVE DATE: February 20, 2008 Federal Emergency Management Agency FLOOD INSURANCE STUDY NUMBER 47189CV000A 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) may not contain all data available within the repository. It is advisable to contact the community repository for any additional data. Part or all of this FIS may be revised and republished at any time. In addition, part of this FIS may be revised by the Letter of Map Revision process, which does not involve republication or redistribution of the FIS. It is, therefore, the responsibility of the user to consult with community officials and to check the community repository to obtain the most current FIS components. Initial Countywide FIS Date: February 20, 2008 TABLE OF CONTENTS Page 1.0 INTRODUCTION 1 1.1 Purpose of Study 1 1.2 Authority and Acknowledgments 1 1.3 Coordination 2 2.0 AREA STUDIED 3 2.1 Scope of Study 3 2.2 Community Description 6 2.3 Principal Flood Problems 6 2.4 Flood Protection Measures 6 3.0 ENGINEERING METHODS 7 3.1 Hydrologic Analyses 7 3.2 Hydraulic Analyses 22 3.3 Vertical Datum 25 4.0 FLOODPLAIN MANAGEMENT APPLICATIONS 26 4.1 Floodplain Boundaries 26 4.2 Floodways 27 5.0 INSURANCE APPLICATIONS 38 6.0 FLOOD INSURANCE RATE MAP 39 7.0 OTHER STUDIES 40 8.0 LOCATION OF DATA 40 9.0 BIBLIOGRAPHY AND REFERENCES 40 TABLE OF CONTENTS - continued Page FIGURES Figure 1 Floodway Schematic 39 TABLES Table 1 Scope of Revision 4-5 Table 2 Summary of Discharges 10-22 Table 3 Manning’s “n” Values- Detailed Studied Streams 24 Table 4 Manning’s “n” Values- Limited Detailed Studied Streams 25 Table 5 Floodway Data 28-37 Table 6 Community Map History 41 EXHIBITS Exhibit 1 - Flood Profiles Bartons Creek Panel 01P-03P Cedar Creek/South Fork Panel 04P-07P Cumberland River Panel 08P-12P Sinking Creek Panel 13P-18P Spring Creek Panel 19P-23P* Stoners Creek Panel 24P-26P Suggs Creek Panel 27P-29P * Sheet 23P Not Printed Exhibit 2 - Flood Insurance Rate Map Index Flood Insurance Rate Map FLOOD INSURANCE STUDY WILSON COUNTY, TENNESSEE AND INCORPORATED AREAS 1.0 INTRODUCTION 1.1 Purpose of Study This countywide Flood Insurance Study (FIS) investigates the existence and severity of flood hazards in the geographic area of Wilson County, Tennessee, including the Cities of Lebanon, Mt. Juliet, and Watertown, and the unincorporated areas of Wilson County (hereinafter referred to collectively as Wilson County). This FIS 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 county that will be used to establish actuarial flood insurance rates. This information will be used by Wilson County to update existing floodplain regulations as part of the regular phase of the National Flood Insurance Program (NFIP), and by local and regional planners to further promotes sound land use and floodplain development. Minimum floodplain management requirements for participation in the National Flood Insurance Program 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. 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. This study was prepared to include all jurisdictions within Wilson County into a countywide format FIS. Information on the authority and acknowledgments for each jurisdiction included in this countywide FIS, as compiled from their previously printed FIS reports, is shown on the following pages. Mt. Juliet, City of, The hydrologic and hydraulic analyses for the Unincorporated Areas: original study of the unincorporated areas of Wilson County and the City of Mt. Juliet were prepared by the U.S. Army Corps of Engineers (USACE), Nashville District, for the Federal Emergency Management Agency (FEMA), under Inter-Agency Agreement No. IAA-H-18- 78, Project Order No. 17. That work was completed in March 1982. 1 Lebanon, City of: The hydrologic and hydraulic analyses for the City of Lebanon were performed by the Nashville District, U.S. Army Corps of Engineers, for FEMA under Interagency Agreement No. IAA-H-18-78, Project Order No. 17. This study was completed in September 1980. The authority and acknowledgments for the City of Watertown are not included because there was no previously printed FIS report for this community. The hydrologic and hydraulic analyses for the FIS report dated May 16, 1994 were prepared by the USACE, Nashville District for FEMA, under Inter-Agency Agreement No. IA-EMW-91-E- 3529, Project Order No. 3. This work was completed in November 1991. The hydrologic and hydraulic analyses for Sinking Creek and Cedar Creek were taken from the FIS for the City of Lebanon, Tennessee (FEMA, 1983). For this countywide revision, the hydrologic and hydraulic analysis for all streams studied by limited detail methods were performed by Watershed IV Alliance, for the Federal Emergency Management Agency (FEMA), under Contract No. EMA-2002-CO-0011A. This work was completed in March 2006. Floodplain boundaries were redelineated based on more up-to-date topography submitted by the State of Tennessee. Base map information shown on the Flood Insurance Rate Map (FIRM) was derived multiple sources. Base map files were provided in digital format by Wilson County Office of Information Technology. This information was photogramically compiled from digital aerial photography dated 2002, 2004, and 2005. Street Centerlines were digitized based on 1999 imagery and updated with georeferenced plat and approved against the 2004 imagery. Stream centerlines were photogrammetrically compiled from digital aerial photography dated 1999. The coordinate system used for the production of this FIRM is Tennessee State Plane (FIPSZONE 4100), North American Datum of 1983 (NAD 83). Corner coordinates shown on the FIRM are in latitude and longitude referenced to the Tennessee State Plane (FIPSZONE 4100) projection, NAD 83. Differences in the datum and spheroid used in the production of FIRMs for adjacent counties may result in slight positional differences in map features at the county boundaries. These differences do not affect the accuracy of information shown on the FIRM. 1.3 Coordination An initial CCO meeting is typically held with representatives of FEMA, the community, and the study contractor to explain the nature and purpose of an FIS, and to identify the streams to be studied by detailed methods. A final CCO meeting is typically held with representatives of FEMA, the community, and the study contractor to review the results of the study. 2 The initial CCO meeting for the unincorporated areas of Wilson County and the City of Mt. Juliet was held in November 1977. This meeting was attended by representatives of Wilson County, the City of Mt. Juliet, the USACE and FEMA. The final CCO meeting for the unincorporated areas of Wilson County was held on July 6, 1983. This meeting was attended by representatives of Wilson County, the USACE and FEMA. The final CCO meeting for the City of Mt. Juliet was held on March 2, 1981. This meeting was attended by representatives of the USACE, FEMA, and the City of Mt. Juliet. For the FIS report dated May 16, 1994, a final CCO meeting was held on April 13, 1993. This meeting was attended by representatives of Wilson County, the City of Mt. Juliet, the USACE, and FEMA. The initial CCO meeting for the City of Lebanon was held in November 1977. The meeting was attended by representatives of the Nashville District, the USACE, FEMA, and the City of Lebanon officials. The final meeting was held on March 2, 1981, with representatives of the USACE, FEMA, and the City of Lebanon in attendance. For this countywide FIS, an initial CCO meeting was held on June 29, 2004. This meeting was attended by representatives of the communities, FEMA, the study contractor, and the State of Tennessee. A final CCO meeting was held on April 20, 2006 and was attended by representatives of the communities, FEMA, and the study contractor. 2.0 AREA STUDIED 2.1 Scope of Study This FIS covers the geographic area of Wilson County, Tennessee. All or portions of the following streams were studied by detailed methods: Bartons Creek, Cedar Creek/South Fork, Cumberland River, Sinking Creek, Spencer Creek, Spring Creek, Stoners Creek, and Suggs Creek. Limits of detailed study are indicated on the Flood Profiles (Exhibit 1) and on the FIRM (Exhibit 2). The areas studied by detailed methods were selected with priority given to all known flood hazard areas and areas of projected development and proposed construction. Limited detail analyses were used to study those areas having a low development potential or minimal flood hazards. The scope and methods of study were proposed to, and agreed upon by, FEMA, the State of Tennessee, and Wilson County. For this countywide study,