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Short Citation:
OCM Partners, 2024: 2010-2011 ARRA Lidar: Calhoun County (TX),

Item Identification

Title: 2010-2011 ARRA Lidar: Calhoun County (TX)
Short Name: tx2011_arra_calhoun_m4985_metadata
Status: Completed
Publication Date: 2016-01-09

This task order is for planning, acquisition, processing, and derivative products of LiDAR data to be collected for Calhoun County, Texas. LiDAR data, and derivative products produced in compliance with this task order are part of the data to be obtained under the American Recovery and Reinvestment Act (ARRA) of 2009. Contract number G10PC00025. Specifications listed below are based on the U.S. Geological Survey National Geospatial Program Base LiDAR Specification, Version 13. Tile names were slightly altered to meet particular naming conventions on NOAA OCM ftp. Dataset was titled 2010 but due to acquisition dates falling in 2011, the name has been updated.

Original contact information:

Contact Name: Patrick Emmett

Contact Org: USGS


Phone: 573-308-3587



USGS has a requirement for LiDAR data over Calhoun County in Texas. Calhoun County is to be collected at a nominal pulse spacing (NPS) of 2.0 meters. The Calhoun County Texas LiDAR Acquisition project is to provide high accuracy bare-earth processed LiDAR data suitable for the project area. The project consisted of acquisition, post-processing, classification of LiDAR data, and creation of final deliverable products. All areas shall be collected at a nominal pulse spacing (NPS) of 2.0 meters based on UTM14, related to the North American Datum of 1983 (NSRS2007). Vertical accuracy was to achieve a RMSE Z of 12.5 cm (95% confidence level of less than 24.5 cm) or better in the "Open Terrain" land cover category for all areas. Accuracy statement is based on areas of moderate to flat terrain. Diminished accuracies are to be expected in areas in dense vegetation. The accuracy of the LiDAR data as tested met or exceeded the vertical accuracy requirements, however, derived products may be less accurate in areas of dense vegetation due to a lesser number of points defining the bare-earth in such areas.



Supplemental Information:

A footprint of this data set may be viewed in Google Earth at:

Reports explaining collection and quality assurance is available at:


Theme Keywords

Thesaurus Keyword
ISO 19115 Topic Category

Physical Location

Organization: Office for Coastal Management
City: Charleston
State/Province: SC

Data Set Information

Data Set Scope Code: Data Set
Maintenance Frequency: As Needed
Data Presentation Form: las
Entity Attribute Overview:

LiDAR points in LAZ format (Classes 1,2,7,9,10)

Entity Attribute Detail Citation:


Distribution Liability:

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

Support Roles

Data Steward

CC ID: 688316
Date Effective From: 2016-01-09
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202


CC ID: 688318
Date Effective From: 2016-01-09
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202

Metadata Contact

CC ID: 688319
Date Effective From: 2016-01-09
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202

Point of Contact

CC ID: 688317
Date Effective From: 2016-01-09
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202


Currentness Reference: Ground Condition

Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 1137487
W° Bound: -96.93059
E° Bound: -96.32088
N° Bound: 28.73151
S° Bound: 28.0639

Extent Group 1 / Time Frame 1

CC ID: 1137486
Time Frame Type: Range
Start: 2010-12-09
End: 2011-02-11

Spatial Information

Spatial Representation

Representations Used

Vector: Yes

Access Information

Security Class: Unclassified
Data Access Procedure:

This data can be obtained on-line at the following URL:;

Data Access Constraints:


Data Use Constraints:

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. These data depict the heights at the time of the survey and are only accurate for that time.

Distribution Information

Distribution 1

CC ID: 742763
Download URL:
File Name: Customized Download

Create custom data files by choosing data area, product type, map projection, file format, datum, etc.

Distribution 2

CC ID: 742764
Download URL:
File Name: Bulk Download

Simple download of data files.



CC ID: 742766
URL Type:
Online Resource


CC ID: 742767
URL Type:
Online Resource


CC ID: 742768
Name: Browse Graphic
URL Type:
Browse Graphic
File Resource Format: kmz

This graphic shows the lidar coverage of the Calhoun County, Texas from 2010 and 2011 to support ARRA of 2009.

Activity Log

Activity Log 1

CC ID: 688335
Activity Date/Time: 2016-05-23

Date that the source FGDC record was last modified.

Activity Log 2

CC ID: 688334
Activity Date/Time: 2017-11-14

Converted from FGDC Content Standards for Digital Geospatial Metadata (version FGDC-STD-001-1998) using '' script. Contact Tyler Christensen (NOS) for details.

Activity Log 3

CC ID: 718651
Activity Date/Time: 2018-02-08

Partial upload of Positional Accuracy fields only.

Activity Log 4

CC ID: 742765
Activity Date/Time: 2018-03-13

Partial upload to move data access links to Distribution Info.

Data Quality


The Fundamental Vertical Accuracy (FVA) of the Classified Bare Earth files for the project area achieved an RMSE of 0.057 meters. Sixty-four (64) 'open terrain' survey control points were used in this evaluation, with an additional 20 'open terrain' points held in reserve and supplied to the client. Additional survey control points were also supplied to the client with 20 points in the category of 'short grass' and 20 points in the category of 'tall grass'.

Horizontal Positional Accuracy:

All Area data products were acquired at or below 2500 meters above mean terrain (AMT) and have a horizontal accuracy of 0.45 meters (per manufacturers system specifications), with a nominal point spacing of 1.5 meters.

Vertical Positional Accuracy:

The Fundamental Vertical Accuracy (FVA) of the Classified Bare Earth for all Areas achieved is 0.111 meters at a 95% confidence level in the "Open Terrain" land cover category. Sixty-four (64) survey control points were used in this evaluation.

; Quantitative Value: 0.111 meters, Test that produced the value: FVA of 11.1 cm. 0.057 m RMSEz (1.96xRMSEz)

Completeness Report:


Conceptual Consistency:



Process Steps

Process Step 1

CC ID: 1137483

The LiDAR data was captured using AeroMetric's twin-engine Cessna 310, fixed wing aircraft equipped with a LiDAR system. The LiDAR system includes a differential GPS unit and inertial measurement system to provide superior positional accuracy.

Acquisition parameters:

1. Flight Height - 2500 meters above mean terrain

2. Swath Width - 34 degrees

3. Sidelap - 30%

4. Nominal Post Spacing - 1.5 meters

GPS and IMU processing parameters:

1. Maximum baseline length - Not greater than 40 kilometers.

2. Number of base stations during LiDAR collection - A minimum of 2.

3. Maximum positional RMS of trajectory during LiDAR collection - 0.10 meters

4. IMU processing monitored for consistency and smoothness - Yes.

Point Cloud Processing:

1. Horizontal Datum - NAD83(NSRS2007)

2. Horizontal Coordinates - Universal Transverse Mercator, Zone 14, in meters.

3. Vertical Datum - NAVD88

4. Geoid Model used to reduce satellite derived elevations to orthometric heights - NGS Geoid09.

LiDAR Processing:

1. Point Cloud data is imported via TerraScan in a Microstation V8 (V) CAD environment on a specified 1500 meter by 1500 meter tiling scheme.

2. Analyze the data for overall completeness and consistency. This is to ensure that there are no voids or anomalies in the data collection.

3. Inspect for calibration errors in the dataset using the TerraMatch software. This is accomplished by sampling the data collected across all flight lines and classify the individual lines to ground. The software will use the ground-classified points by flightline to compute corrections (Heading, Pitch, Roll, and Scale).

4. Orientation corrections (i.e. Calibration corrections) are applied (if needed) to the entire dataset.

5. Automatic ground classification is performed using algorithms with customized parameters to best fit the project area. Several areas of varying relief and planimetric features were inspected to verify the final ground surface.

6. AeroMetric, Inc. provided Quality Assurance and Quality Control (QA/QC) data for this project. AeroMetric captured QA/QC points in 'open terrain' land cover category that were used to test the accuracy of the LiDAR ground surface. TerraScan's Output Control Report (OCR) was used to compare the QA/QC data to the LiDAR data. This routine searches the LiDAR dataset by X and Y coordinate, finds the closest LiDAR point and compares the vertical (Z) values to the known data collected in the field. Based on the QA/QC data, a bias adjustment was determined, and the results were applied (if necessary) to the LiDAR data. A final OCR was performed with a resulting RMSE of 0.057 meters for the project.

7. Each tile is reviewed for accuracy and consistency of the macro ground classification.

8. Once the automatic processing and the testing of LiDAR is complete, AeroMetric meticulously reviews the generated bare-earth surface data to ensure that proper classification was achieved as part of a Quality Control process.

9. Final deliverables are generated and output to a client specified 1500 meters by 1500 meters tiling scheme.

Process Date/Time: 2011-05-02 00:00:00

Process Step 2

CC ID: 1137484

The NOAA Office for Coastal Management (OCM) downloaded topographic files (point clouds) in LAZ format from an USGS ftp site. The data was received in UTM Zone 14 North (in meters) and vertical coordinates were referenced to NAVD88 in meters using the Geoid09 model. OCM performed the following processing for data storage and Digital Coast provisioning purposes:

1. The All-Return LAZ files were checked for erroneous outliers removed.

2. The LAZ files were converted from a UTM coordinates to Geographic Coordinates (decimal degrees), then converted to ellipsoidal vertical units in meters with respect to the Geoid09.

Process Date/Time: 2015-12-20 00:00:00

Catalog Details

Catalog Item ID: 50045
GUID: gov.noaa.nmfs.inport:50045
Metadata Record Created By: Anne Ball
Metadata Record Created: 2017-11-15 15:23+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2022-08-09 17:11+0000
Metadata Record Published: 2022-03-16
Owner Org: OCMP
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Last Review Date: 2022-03-16
Metadata Review Frequency: 1 Year
Metadata Next Review Date: 2023-03-16