2022 IN DNR Lidar: Indiana Coastline

Product: These lidar data are processed Classified LAS 1.4 files, formatted to 1995 individual 1250 ft x 1250 ft tiles clipped to the DPA; used to create intensity images, 3D breaklines, and hydro-flattened DEMs as necessary.

Geographic Extent: LaPorte, Lake, and Porter counties in Indiana (and small portions of Cook County, Illinois and Berrien County, Michigan), covering approximately 112 square miles.

Dataset Description: The lidar project called for the planning, acquisition, processing, and derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.35 meters. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification 2021, Revision A. The data was developed based on a horizontal projection/datum of NAD83(HARN), Indiana West Feet, and vertical datum of NAVD88 (GEOID18) Feet. Lidar data was delivered as processed Classified LAS 1.4 files, formatted to 1995 individual 1250 ft x 1250 ft tiles clipped to the DPA, as tiled Intensity Images and tiled bare-earth DEMs; all tiled to the same 1250 ft x 1250 ft schema.

Ground Conditions: Lidar was collected in April 2022, while no snow was on the ground and rivers were at or below normal levels.

Sanborn Map Company, Inc. established a total of 25 accuracy check points, 20 in Bare Earth and Urban landcovers (20 NVA points), 5 in Tall Grass and Brushland/Low Trees categories (5 VVA points), that were used to assess the vertical accuracy of the data.

These data were received by the NOAA Office for Coastal Management (OCM) from the Indiana Dept. of Natural Resources (IN DNR). NOAA OCM processed the data to be available for custom and bulk downloads from the NOAA Digital Coast Data Access Viewer (DAV). In addition to the lidar point data, topobathy bare earth Digital Elevation Models (DEMs) at a 1 foot grid spacing, created from the lidar point data are also available from the NOAA Digital Coast. The link to these data and the hydro breaklines are provided in the URL section of this metadata record. Reports and hillshade rasters are available by request at coastal.info@noaa.gov.

To acquire detailed surface elevation data for use in conservation planning, design, research, floodplain mapping, dam safety assessments, and elevation modeling, etc. Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create Intensity Images, Breaklines and Raster DEM. The purpose of these lidar data was to produce high accuracy 3D hydro-flattened Digital Elevation Model (DEM) with a 1 ft cell size.

These lidar point cloud data were used to create intensity images, 3D breaklines, and hydro-flattened DEMs as necessary.

Sanborn Map Company, Inc.

The following are the USGS lidar fields in JSON:

{

"ldrinfo" : {

"ldrspec" : "U.S. Geological Survey (USGS) - National Geospatial Program (NGP) Lidar Base Specification 2021, Revision A",

"ldrsens" : "Riegl VQ-1560 II",

"ldrmaxnr" : "15",

"ldrnps" : "0.34",

"ldrdens" : "8.8",

"ldranps" : "0.34",

"ldradens" : "8.8",

"ldrfltht" : "1486",

"ldrfltsp" : "169",

"ldrscana" : "58.5",

"ldrscanr" : "360",

"ldrpulsr" : "2310",

"ldrpulsd" : "4",

"ldrpulsw" : "0.26",

"ldrwavel" : "1064",

"ldrmpia" : "1",

"ldrbmdiv" : "0.25",

"ldrswatw" : "1664",

"ldrswato" : "20",

"ldrgeoid" : "National Geodetic Survey (NGS) Geoid18"

},

"ldraccur" : {

"ldrchacc" : "0.5",

"rawnva" : "0.229",

"rawnvan" : "20",

"clsnva" : "0.216",

"clsnvan" : "20",

"clsvva" : "0.117",

"clsvvan" : "5"

},

"lasinfo" : {

"lasver" : "1.4",

"lasprf" : "6",

"laswheld" : "Withheld (ignore) points were identified in these files using the standard LAS Withheld bit.",

"lasolap" : "Swath "overage" points were not identified in these files.",

"lasintr" : "16",

"lasclass" : {

"clascode" : "1",

"clasitem" : "Processed, but Unclassified"

},

"lasclass" : {

"clascode" : "2",

"clasitem" : "Bare Earth Ground"

},

"lasclass" : {

"clascode" : "7",

"clasitem" : "Low Noise"

},

"lasclass" : {

"clascode" : "9",

"clasitem" : "Water"

},

"lasclass" : {

"clascode" : "17",

"clasitem" : "Bridge Decks"

},

"lasclass" : {

"clascode" : "18",

"clasitem" : "High Noise"

},

"lasclass" : {

"clascode" : "20",

"clasitem" : "Ignored Ground"

}

}}

Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners.

Data is available online for bulk and custom downloads.

None

Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations.

Riegl RiProcess; GeoCue; Windows 10 Operating System

This data set was tested to meet ASPRS Positional Accuracy Standard for Digital Geospatial Data (2014) for a 10cm RMSEz Vertical Accuracy Class. The lidar dataset was evaluated using a total of twenty-five (25) check points (20 NVA + 5 VVA). The result provided a vertical accuracy that fell within project specifications.

Actual NVA accuracy was found to be RMSEz = 3.35cm, equating to +/- 6.58cm at 95% confidence level. Actual VVA accuracy was found to be +/- 3.57cm at the 95th percentile.

These LAS data files include all data points collected. No points have been removed or excluded. A visual qualitative assessment was performed to ensure data completeness. No void areas or missing data exist. The raw point cloud is of good quality and data passes Non-Vegetated Vertical Accuracy specifications.

Data covers the DPA specified for this project.

Data is backed up to tape and to cloud storage.

The Sanborn Map Company, Inc., collected lidar data for the Indiana (and small portions of the Illinois and Michigan) Lake Michigan coastline, for the Indiana Department of Natural Resources (IN DNR). The IN DNR provided the data to NOAA OCM for data distribution via the NOAA Digital Coast.