| snippet:
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Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map (FIRM), Lee County and Incorporated Areas, Alabama, USA |
| summary:
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Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map (FIRM), Lee County and Incorporated Areas, Alabama, USA |
| extent:
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[[-85.750287503557,32.3728752253045],[-84.9976856391784,32.7521662684315]] |
| accessInformation:
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| thumbnail:
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thumbnail/thumbnail.png |
| maxScale:
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1.7976931348623157E308 |
| typeKeywords:
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["Data","Service","Map Service","ArcGIS Server"] |
| description:
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The FIRM Database consists of vector files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The published effective FIRM and FIRM Database are issued as the official designation of the SFHAs. As such they are adopted by local communities and form the basis for administration of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for public review, appeals and corrections of the flood risk information shown to better match real world conditions. As with any engineering analysis of this type, variation from the estimated flood heights and floodplain boundaries is possible. Details of FEMA's requirements for the FISs and flood mapping process that produces these data are available in the Guidelines and Standards for Flood Risk Analysis and Mapping. Attribute accuracy was tested by manual comparison of source graphics with hardcopy plots and a symbolized display on an interactive computer graphic system. |
| licenseInfo:
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<div>Data contained in the FIRM Database files reflect the content of the source materials. Features may have been eliminated or generalized on the source graphic, due to scale and legibility constraints. With new mapping, FEMA plans to maintain full detail in the spatial data it produces. However, older information is often transferred from existing maps where some generalization has taken place. Flood risk data are developed for communities participating in the NFIP for use in insurance rating and for floodplain management. Flood hazard areas are determined using statistical analyses of records of river flow, storm tides, and rainfall; information obtained through consultation with the communities; floodplain topographic surveys; and hydrological and hydraulic analysis. Generally, regulatory water surface elevations and/or regulatory floodways are published only for developed or developing areas of communities. For areas where little or no development is expected to occur, FEMA may generate flood risk data without published water surface elevations. Typically, only drainage areas that are greater than one square mile and with an average of one foot of flood depth or greater are studied.</div><div><br /></div><div>The FIRM Database consists of vector files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The published effective FIRM and FIRM Database are issued as the official designation of the SFHAs. As such they are adopted by local communities and form the basis for administration of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for public review, appeals and corrections of the flood risk information shown to better match real world conditions. As with any engineering analysis of this type, variation from the estimated flood heights and floodplain boundaries is possible. Details of FEMA's requirements for the FISs and flood mapping process that produces these data are available in the Guidelines and Standards for Flood Risk Analysis and Mapping. </div><div><br /></div><div>The reliability of the floodplain boundary delineation is quantified by comparing the computed flood elevation to the ground elevation at the mapped floodplain boundary. The tolerance for how precisely the flood elevation and the ground elevation must match varies based on the flood risk class, which is a function of population, population density, and/or anticipated growth in floodplain areas. A horizontal accuracy of +/- 38 feet is used to determine the compliance with the vertical tolerances defined for each risk class. The range of differences between the ground elevation (defined from the topographic data used for the Flood Risk Project) and the computed flood elevation is between +/- 1.0 foot at the 95% confidence interval for areas with high population within the floodplain, and/or high anticipated growth, and Special Flood Hazard Areas (SFHAs) with high flood risk to +/- one-half the contour interval at the 85% confidence interval for areas with low population and densities within the floodplain, and small or no anticipated growth, and SFHAs with low flood risk. Independent quality control testing of the FIRM database was also performed.</div> |
| catalogPath:
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|
| title:
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FloodMap |
| type:
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Map Service |
| url:
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|
| tags:
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["FEMA","FIRM","Flood Hazard Zone","Food Hazard Area","Floodway","hydrology","Lee County","flood","flood hazard"] |
| culture:
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en-US |
| name:
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FloodMap |
| guid:
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F49DE69D-6431-4D10-AE86-9051376C35BF |
| minScale:
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0 |
| spatialReference:
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NAD_1983_StatePlane_Alabama_East_FIPS_0101_Feet |