Digital Flood Insurance Rate Map Database, Mercer County, PA

Resource lineage description

source

source description  Source Contribution: Spatial and attribute information for the index of USGS 7.5-Minute Series Topographic Map boundaries. (S_Quad_Index)Source Type digital raster data

source citation

Title DOQQ

publication  Date   1994-01-01

cited responsible party - originator

organisation Name  U.S. Geological Survey

source

source description  Source Contribution: The PAMAP 2005 natural color orthoimages were produced at 1-foot pixel resolution and 1:2,400 scale. Each orthoimage provides imagery for a 10,000 x 10,000 ft. block on the ground. The orthoimage filenames were derived from the northwest corner of each ortho tile using the first four digits of the northing and easting coordinates referenced to the Pennsylvania State Plane coordinate system, followed by the State designator "PA," and the State Plane zone designator "N." (S_Base_Index, S_Gen_Struct)Source Type digital raster data

source citation

Title ORTHOIMAGERY, MERCER COUNTY, PA, USA

publication  Date   2006-04-20

cited responsible party - originator

organisation Name  PAMAP Program, PA Department of Conservation and Natural Resources, Bureau of Topographic and Geologic Survey

source

source description  Source Contribution: Geodetic data comprise the results of geodetic surveys to determine among other things, latitude, longitude, height, scale, and orientation control. The NGS? final product is the geodetic data sheet. Geodetic data sheets are comprehensive summaries of all the published information for a given geodetic reference point, including: the geographic position and/or height based on the current reference datum, condition of the survey mark when it was last visited, a description of where the point is located and how to reach it, and an explanation of the terms used in the data sheet. (S_PERM_BMK)Source Type digital vector data

source citation

Title Permanent Bench Mark Data Sheets

publication  Date   2002-01-01

cited responsible party - originator

organisation Name  National Geodetic Survey

source

source description  Source Contribution: Spatial and attribute information. (S_POL_AR, S_POL_LN)Source Type digital vector data

source citation

Title Pennsylvania Municipality boundaries 2005

publication  Date   2004-01-01

cited responsible party - originator

organisation Name  Pennsylvania Department of Transportation, Bureau of Planning and Research, Cartographic Information Division

source

source description  Source Contribution: Spatial and attribute information. (S_WTR_AR, S_WTR_LN)Source Type digital vector data

source citation

Title National Hydrography Dataset

publication  Date   2005-01-01

cited responsible party - originator

organisation Name  U.S. Geological Survey, U.S. Environmental Protection Agency.

source

source description  Source Contribution: This file was significantly altered from the original version by the study contractor. (S_FIRM_Pan)Source Type digital raster data

source citation

Title DOQQ

publication  Date   1994-01-01

cited responsible party - originator

organisation Name  U.S. Geological Survey

source

source description  Source Contribution: Spatial and attribute information. (S_WTR_LN)Source Type digital vector data

source citation

Title Mercer County Hydro

publication  Date   2008-01-01

cited responsible party - originator

organisation Name  Mercer County Regional Planning Commission

source

source description  Source Contribution: Case Number 95-03-069P (S_LOMR)Source Type map

source citation

Title Effective letters of Map Change

publication  Date   1995-06-01

cited responsible party - originator

organisation Name  Federal Emergency Management Agency

source

source description  Source Contribution: Spatial and attribute information. (S_Wtr_Ln)Source Type paper

source citation

Title Flood Insurance Study for Township of Shenango, PA dated 19910904, Township of Hempfield, PA dated 19910215, Borough of Greenville, pA dated 19810716, Borough of Sandy Lake, Borough of Stoneboro, and Township of South Pymatuning, PA dated 19910318, City of Sharon, PA dated 19781017, City of Hermitage, PA dated 19810930, Borough of Mercer, PA dated 19770315, Borough of Grove City, PA dated 19770930, City of Farrell, PA dated 19780417, Borough of West Middlesex, PA dated 19910904.

publication  Date   1991-01-01

cited responsible party - originator

organisation Name  Federal Emergency Management Agency

source

source description  Source Contribution: Spatial and attribute information. (S_Riv_Mrk)Source Type map

source citation

Title Flood Insurance Study for Township of Shenango, PA dated 19910904.

publication  Date   1991-09-04

cited responsible party - originator

organisation Name  Federal Emergency Management Agency

source

source description  Source Contribution: Spatial and attribute information. (S_Trnsport_Ln)Source Type digital vector data

source citation

Title Mercer County Transport lines, 2005

publication  Date   2004-01-01

cited responsible party - originator

organisation Name  Pennsylvania Department of Transportation, Bureau of Planning and Research, Cartographic Information Division

source

source description  Source Contribution: Spatial and attribute information. (S_BFE)Source Type digital vector data

source citation

Title Floodplain Mapping for Mercer County, Pennsylvaina

publication  Date   2009-09-11

cited responsible party - originator

organisation Name  Greenhorne & O'Mara (GG3)

source

source description  Source Contribution: Spatial and attribute information. (S_fld_haz_ar)Source Type digital vector data

source citation

Title Floodplain Mapping for Mercer County, Pennsylvaina

publication  Date   2009-09-11

cited responsible party - originator

organisation Name  Greenhorne & O'Mara (GG3)

source

source description  Source Contribution: Spatial and attribute information. (S_Wtr_ln)Source Type digital vector data

source citation

Title Floodplain Mapping for Mercer County, Pennsylvaina

publication  Date   2009-09-11

cited responsible party - originator

organisation Name  Greenhorne & O'Mara (GG3)

AbsoluteExternalPositionalAccuracy

name Of Measure Horizontal Positional Accuracy Report

evaluation Method Description  The DFIRM Database consists of community based vector files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The published effective FIRM and DFIRM 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 Specifications for Flood Hazard Mapping Partners. Horizontal accuracy was tested by manual comparison of source graphics with hardcopy plots and a symbolized display on an interactive computer graphic system. Independent quality control testing of FEMA's DFIRM database was also performed.

AbsoluteExternalPositionalAccuracy

name Of Measure Vertical Positional Accuracy Report

evaluation Method Description  The DFIRM Database consists of community based vector files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The published effective FIRM and DFIRM maps 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 Specifications for Flood Hazard Mapping Partners. Vertical accuracy was tested by manual comparison of source graphics with hardcopy plots and a symbolized display on an interactive computer graphic system. Independent quality control testing of FEMA's DFIRM database was also performed.

Completeness Commission

evaluation Method Description  Data contained in the DFIRM 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. Both detailed and approximate analyses are employed. Generally, detailed analyses are used to generate flood risk data only for developed or developing areas of communities. For areas where little or no development is expected to occur, FEMA uses approximate analyses to generate flood risk data. Typically, only drainage areas that are greater than one square mile are studied.

Completeness Omission

evaluation Method Description  Data contained in the DFIRM 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. Both detailed and approximate analyses are employed. Generally, detailed analyses are used to generate flood risk data only for developed or developing areas of communities. For areas where little or no development is expected to occur, FEMA uses approximate analyses to generate flood risk data. Typically, only drainage areas that are greater than one square mile are studied.

ConceptualConsistency

measure Description  When FEMA revises an FIS, adjacent studies are checked to ensure agreement between flood elevations at the boundaries. Likewise flood elevations at the confluence of streams studied independently are checked to ensure agreement at the confluence. The FIRM and the FIS are developed together and care is taken to ensure that the elevations and other features shown on the flood profiles in the FIS agree with the information shown on the FIRM. However, the elevations as shown on the FIRM are rounded whole-foot elevations. They must be shown so that a profile recreated from the elevations on the FIRM will match the FIS profiles within one half of one foot.