2008 City of Baltimore Lidar

In the spring of 2008, the City of Baltimore expressed an interest to upgrade the City GIS Database with mapping quality airborne LiDAR data.

The City of Baltimore currently had in place a contract for mapping GIS/services with the KCI/Sanborn Joint Venture Partnership, L.L.C. under

Project 1051. The City of Baltimore issued Change Order #1 on on Project 1051 for the LiDAR acquisition and processing. KCI/Sanborn acquired

the LiDAR data over the City of Baltimore (approximately 90 square miles) during one long mission on 15 April 2008.

A Leica Airborne Airborne Laser Scanner Model ALS 50 was used in a Sanborn Aero Commander 500B (Registration N6172X) to acquire the data. The

airborne mission was flown 15 April 2008. The LiDAR system acquired calibration data the same day by conducting flight passes over a known

ground surface before and the LiDAR mission. During final data processing, the calibration parameters were used in the final post-processing

software.

The acquired LiDAR data were processed to obtain the following deliverables:

-DEMs of first and last returns and bare earth (all point data)

-LAS format data in a tile grid provided by the City/KCI

-Gridded DEM in ESRI format (Arc Binary Grid -Arc/INFO Lattice ) produced from Bare Earth Mass Points in 1-meter resolution (Grid size)

-Associated FGDC compliant metadata in XML format

The project specifications called for the LiDAR survey to comply with industry standard FEMA guidelines for accuracy. The FEMA requirement for

this type of mapping calls for vertical errors not to exceed 0.185 meter (0.61 feet) RMSE when compared with ground check points over open

flat terrain and 0.370 meter (1.22 feet) for other types of terrain. This accuracy requirement was comfortably met with comparing LiDAR

derived elevations against 50 ground control check points provided by KCI Technologies. These control points were photo control points used

as part of the photogrammetric mapping project and independent LiDAR checkpoints surveyed by KCI and Mercado after the data was delivered. The

RMSE error observed was 0.058 meter (0.189 feet) over all 50 check points.

Original contact information:

Contact Name: Josh Nimetz

Contact Org: KCI/Sanborn Joint Venture Partnership, L.L.C. (hereafter referred to as KCI/Sanborn)

Title: LiDAR Production Manager

Phone: 719-264-5513

Email: jnimetz@sanborn.com

This LIDAR operation was designed to provide a high density set of masspoints within the defined areas. The data sets are suitable for the

development of contours for use in hydraulic/hydrologic model development, and for assessing environmental impacts. Typical uses for the

dataset include FEMA Flood Map Modernization, DFIRM map updates, watershed delineation and other hydro studies per FEMA specifications, as well

as general use by the City of Baltimore.

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

https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/1199/supplemental/2008_City_of_Baltimore_Lidar.kmz

A detailed description of this dataset can be found in the Final Project Report, found here:

https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/1199/supplemental/2008_City_of_Baltimore_Lidar_QA_Report.pdf

Any conclusions drawn from the analysis of this information are not the responsibility of the Office for Coastal Management

or its partners.

This data can be obtained on-line at the following URL: https://coast.noaa.gov/dataviewer;

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

Microsoft Windows 2000 Version 5.2 (Build 3790) Service Pack 2; ESRI ArcCatalog 9.3.0.1770

The project specifications called for the LiDAR survey to comply with industry standard FEMA guidelines for

horizontal accuracy.

; Quantitative Value: 1.0 meters, Test that produced the value: Assumed to meet FEMA specifications for horizontal accuracy.

The FEMA requirements call for vertical errors not to exceed 0.185 meter (0.61 feet) RMSE when compared

with ground check points over open flat terrain.

; Quantitative Value: 0.058 meters, Test that produced the value:

The LiDAR derived elevations for this project compared against 50 ground control check points

showed the RMSE error observed was 0.058 meters.

None provided

All LAS formatted LiDAR data are validated to ensure that data on delivery media is in correct physical format

and is readable and correctly georeferenced and projected. Note that LiDAR intensity is not calibrated or normalized.