FEMA Special Flood Hazard Areas, 2006 - Alachua County, Florida

Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator: Dewberry, Inc of Fairfax VA
Publication_Date: June 22, 2004
Publication_Time: Unknown
Title: FEMA Special Flood Hazard Areas, 2006
Geospatial_Data_Presentation_Form: vector digital data
Publication_Information:
Publication_Place: Gainesville, Florida
Publisher: City of Gainesville
Online_Linkage: \\XTC0883\C$\coleyd\FloodZoneGDB\FEMA2001.mdb
Description:
Abstract:
This dataset is a digital representation of floodzones typically found in Flood Insurance Rate Maps (FIRMs) published by Federal Emergency Management Agency (FEMA). The data are derived from a floodstudy conducted for Alachua County and the City of Gainesville, Florida in 2001.
Purpose:
These data are designed to provide the locations of Special Flood Hazard Areas(SFHA) and zones of possible risks associated with food inundation. In addition to locational and topological information, features contained in the data set include 1%(100 year) and 0.2% (500 year) annual chance flood plain boundaries. Floodway boundaries are included for areas where a baseflood elevation has been determined for portions of streams within Alachua County.
Supplemental_Information:
This dataset was initially delivered by FEMA via its contractor Dewberry Davis Inc. to the City of Gainesville, who is also the creator of this metadata. It then underwent an intense process from the City of Gainesville and the Department of Public Works at Alachua County, which included data conversion, data clean up, data standardization, data documentation and quality control referencing FEMA's paper maps. This process was indespensable so that the digital data received by FEMA in CAD format, could be brought into a GIS system and used in conjunction with land administration records and other geo-referenced land information systems. After the data was brought into an acceptable GIS format, it then underwent through several processes at the Department of Growth Management of Alachua County, where digital maps (static and dynamic) were created for the entire county. These maps were then implemented into two searcheable geo-web applications, the Map Atlas and the GeoGM Mapper, and were made available on line, along with the data itself. For many months, before they became effective at the end of June 2006, their draft version was available on the web from Alachua County for public input, in addition to the FEMA 1996. The dataset and maps were developed in 2004 but became effective in 2006. The official FEMA DFIRM is still not availabe for Alachua County, but feel free to click at FEMA's Map Service Center.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 2001
Ending_Date: January 22, 2004
Currentness_Reference: ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: Irregular
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -82.666055
East_Bounding_Coordinate: -82.036935
North_Bounding_Coordinate: 29.947428
South_Bounding_Coordinate: 29.415216
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Floodzones
Theme_Keyword: Flood Insurance Rate Maps (FIRMS)
Theme_Keyword: Federal Emergency Management Administraion (FEMA)
Place:
Place_Keyword: Alachua County
Place_Keyword: Florida
Access_Constraints: None
Use_Constraints: These data went into effect in 2006.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Dewberry, Inc.
Contact_Address:
Address_Type: mailing address
Address: 8401 Arlington Boulevard
City: Fairfax
State_or_Province: VA
Postal_Code: 22031-4666
Country: USA
Data_Set_Credit:
David Coley City of Gainesville Public Works Dept. Minor edits by Juna Papajorgji, Alachua County
Native_Data_Set_Environment:
Microsoft Windows 2000 Version 5.0 (Build 2195) Service Pack 4; ESRI ArcCatalog 9.1.0.722
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
Floodzone identification was manually cross-checked with the aid of hard-copy FIRM maps created by the dataset originator, Dewberry Inc. No other accuracy tests were performed.
Quantitative_Attribute_Accuracy_Assessment:
Logical_Consistency_Report:
All polygon features are checked for topology errors using the ArcGIS software. Each polygon begins and ends at the same point with the node feature. All nodes are checked for errors so that there are no dangling features. Since the data are stored as a feature class within a personal geodatabase, duplicate lines exist as part of coincident topological structure. All nodes will snap together and close polygons based on a tolerance of 3 feet. If the node is not within the tolerance it is adjusted manually. The tests for logical consistency are performed in ArcGIS, where the following rules were created to check for errors : Polygons must not overlap. Polygons must not have gaps.
Completeness_Report:
All floodzone types that occur in Alachua County are completely mapped. Base Flood Elevations (where calculated) are rounded to the whole foot. Floodway boundaries were computed at surveyed cross sections and interpolated between cross sections. Not all FEMA designated floodzone types occur in Alachua County, e.g. coastal floodzones.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
This data set is assumed to be within National Map Accuracy Standards at a nominal scale of 1:12000. As such, not more than 10 percent of the points tested shall be in error by more than 1/30 inch (+/-20 ft) at scales larger than 1:20000. See: <http://rockyweb.cr.usgs.gov/nmpstds/nmas.html> for a complete desription of these standards.
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
All elevations are refereced to NAVD 1988. No accuracy assesment has been performed.
Lineage:
Source_Information:
Source_Scale_Denominator: 12000
Type_of_Source_Media: CD-ROM
Process_Step:
Process_Description:
The data were obtained from Dewberry, Inc. in the form of Microstation DGN (CAD) files, where each file represents one FIRM panel. The data were then converted from DGN to Geodatabase using the ArcGIS command CAD to GeoDatabase, where each layer became a geodatabase feature class.
Process_Date: June, 2005
Process_Step:
Process_Description:
Each FIRM panel was then joined to its adjacent panel using the ArcGIS command append. Upon completion, a merge command was run to remove panel boundaries. Sliver polygons and overlaps were cleaned by establishing feature class topoolgy rules for polygons described elsewhere in this document. Each polygon was then assigned attributes according to the available DGN file annotation layer and converted from UTM ZONE 17N to Florida State Plane North coordinate systems. Finally, all data were subjected to a QA-QC process with the aid of accompanying hardcopy FIRM panel(s).
Process_Date: June, 2005
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: David Coley
Contact_Organization: City of Gainesville
Contact_Position: GIS Analyst
Contact_Voice_Telephone: 352-393-8423
Process_Step:
Process_Description: Dataset exported to Shapefile.
Source_Used_Citation_Abbreviation: C:\DOCUME~1\coleydm\LOCALS~1\Temp\xml11.tmp
Process_Date: Aug. 2005
Process_Step:
Process_Description: Metadata Imported.
Process_Date: Sept. 2005
Cloud_Cover: N/A
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: G-polygon
Point_and_Vector_Object_Count: 1731
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: Lambert Conformal Conic
Lambert_Conformal_Conic:
Standard_Parallel: 29.583333
Standard_Parallel: 30.750000
Longitude_of_Central_Meridian: -84.500000
Latitude_of_Projection_Origin: 29.000000
False_Easting: 1968500.000000
False_Northing: 0.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.000512
Ordinate_Resolution: 0.000512
Planar_Distance_Units: survey feet
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257222
Vertical_Coordinate_System_Definition:
Altitude_System_Definition:
Altitude_Datum_Name: North American Vertical Datum of 1988
Altitude_Resolution: 0.000010
Altitude_Distance_Units: Feet
Altitude_Encoding_Method:
Explicit elevation coordinate included with horizontal coordinates
Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: FEMA04
Attribute:
Attribute_Label: OBJECTID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: FID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: SHAPE
Attribute_Definition: Feature geometry.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: ZONE_
Attribute_Definition:
This attribute identifies each polygons floodzone status. Zones A, AE and AO are identified as Special Flood Hazard Areas subject to inundation by the 1% annual chance flood. Zone AO indicates an area of flood depths of 1 to 3 feet. Zone X500 indicates areas subject to inundation by the 0.2% annual chance flood. Zone X indicates areas that are outside the 0.2% chance annual flood.
Attribute_Definition_Source: FEMA
Attribute:
Attribute_Label: FLOODWAY
Attribute_Definition:
Designates an area as IN or OUT of the floodway. The floodway is defined as that area adjacent to the stream channel that must remain clear of structures such that the BFE as calculated will remain unaffected.
Attribute_Definition_Source: FEMA
Attribute:
Attribute_Label: Shape
Attribute_Definition: Feature geometry.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: ID_
Overview_Description:
Distribution_Information:
Resource_Description: Downloadable Data
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Transfer_Size: 5.953
Metadata_Reference_Information:
Metadata_Date: 20061020
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: David Coley
Contact_Organization: City of Gainesville
Contact_Position: GIS Analyst
Contact_Address:
Address_Type: mailing address
Address: PO Box 490
City: Gainesville
State_or_Province: Florida
Postal_Code: 32602-0490
Country: United States
Contact_Voice_Telephone: 352-393-8423
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Access_Constraints: None
Metadata_Use_Constraints: None
Metadata_Extensions:
Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>
Profile_Name: ESRI Metadata Profile
Metadata_Extensions:
Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>
Profile_Name: ESRI Metadata Profile
Generated by mp version 2.8.6 on Fri Oct 20 16:54:20 2006