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Short Citation:
OCM Partners, 2023: Lidar for the Pocomoke and Atlantic Coastal Watersheds in Maryland,

Item Identification

Title: Lidar for the Pocomoke and Atlantic Coastal Watersheds in Maryland
Short Name: 2011 USDA lidar: Pocomoke and Atlantic Coastal
Status: Completed
Publication Date: 2018

This Light Detection and Ranging (LiDAR) dataset is a survey of the Pocomoke and Atlantic Coastal Watersheds in Maryland. The project area consists of approximately 500 square miles. The project design of the LiDAR data acquisition was developed to support a nominal post spacing of 0.70 meter. Fugro EarthData, Inc. acquired 151 flight lines in eight lifts on February 6, 7, 9, 13, 15, and 16, 2011; in tidal areas, data was collected within 2 hours (before or after) of mean low tide. The data was divided into 1500 by 1500 meter cells that serve as the tiling scheme. LiDAR data collection was performed with a Piper Navajo twin engine aircraft, utilizing a Leica ALS60 MPiA sensor, collecting multiple return x, y, and z as well as intensity data. LiDAR data is remotely sensed high-resolution elevation data collected by an airborne collection platform. This data of the Pocomoke and Atlantic Coastal Watersheds in Maryland, was collected at sufficient resolution to provide a nominal point spacing of 0.70 meter for collected points. Up to 4 returns were recorded for each pulse in addition to an intensity value.


The data was collected for the NRCS, whose mission is Helping People Help the Land. NRCS provides products and services that enable people to be good stewards of their soil, water, and related natural resources. With their assistance, people are better able to conserve, maintain, or improve their natural resources.


Obtained by NOAA from the Maryland iMAP system (


Theme Keywords

Thesaurus Keyword
ISO 19115 Topic Category
None bare earth
None bare ground
None high-resolution
None Light Detection and Ranging

Spatial Keywords

Thesaurus Keyword
Geographic Names Information System Maryland
Geographic Names Information System Pocomoke and Atlantic Coastal Watersheds

Physical Location

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

Data Set Information

Data Set Scope Code: Data Set
Data Set Type: GIS Files
Maintenance Frequency: As Needed
Data Presentation Form: Map (digital)
Entity Attribute Overview:

Lidar point cloud x,y,z and intensity data with classification scheme: 1 = undefined, 2 = ground, 7 = low noise, 9 = water, 10 = ignored ground, 11 = withheld

Distribution Liability:

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

Data Set Credit: Fugro Earthdata, USDA-NRCS

Support Roles

Data Steward

CC ID: 722850
Date Effective From: 2018-02-26
Date Effective To:
Contact (Organization): Office for Coastal Management (OCM)
Address: 2234 South Hobson Avenue
Charleston, SC 29405-2413


CC ID: 722832
Date Effective From: 2018-02-26
Date Effective To:
Contact (Organization): Office for Coastal Management (OCM)
Address: 2234 South Hobson Avenue
Charleston, SC 29405-2413

Metadata Contact

CC ID: 722851
Date Effective From: 2018-02-26
Date Effective To:
Contact (Organization): Office for Coastal Management (OCM)
Address: 2234 South Hobson Avenue
Charleston, SC 29405-2413

Point of Contact

CC ID: 722853
Date Effective From: 2018-02-26
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: 1140731
W° Bound: -75.691501
E° Bound: -75.225534
N° Bound: 38.453581
S° Bound: 37.952398

Extent Group 1 / Time Frame 1

CC ID: 1140730
Time Frame Type: Range
Start: 2011-02
End: 2011-06

Spatial Information

Spatial Resolution

Horizontal Distance: 0.7 Meter

Spatial Representation

Representations Used

Vector: Yes

Vector Representation 1

CC ID: 722836
Point Object Present?: Yes
Point Object Count: 1149847022

Access Information

Security Class: Unclassified
Data Access Procedure:

Access via online tool

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.

Distribution Information

Distribution 1

CC ID: 722838
Start Date: 2018-03-14
End Date: Present
Download URL:
Distributor: Office for Coastal Management (OCM) (2018-02-26 - Present)

Customizable download of point cloud data and derived products.

File Type: LAZ
Compression: Zip



CC ID: 722847
Name: Digital Coast
URL Type:
Online Resource


CC ID: 722848
Name: Maryland iMAP
URL Type:
Online Resource

Location of the originating point clouds.

Data Quality

Vertical Positional Accuracy:

The minimum expected vertical accuracy was tested to meet or exceed the National Standard for Spatial Data Accuracy. When compared to GPS survey grade points in generally flat non-vegetated areas, at least 95% of the positions had an error less than or equal to 18 cm (equivalent to root mean square error of 9.25 cm if errors were normally distributed).

Data Management

Have Resources for Management of these Data Been Identified?: Yes
Approximate Percentage of Budget for these Data Devoted to Data Management: Unknown
Do these Data Comply with the Data Access Directive?: Yes
Is Access to the Data Limited Based on an Approved Waiver?: No
Actual or Planned Long-Term Data Archive Location: NCEI-CO


Lineage Statement:

Original acquisition and processing of lidar data was completed by Fugro EarthData, Inc. and delivered to NRCS and Maryland. NOAA OCM obtained the data from Maryland iMAP and modified for ingest into the Digital Coast system.


Lidar data from Maryland iMAP

CC ID: 1140723
Extent Type: Range
Extent Start Date/Time: 2011-02-06
Extent End Date/Time: 2011-02-16
Citation URL:
Source Contribution:

Point cloud data repository for Maryland

Process Steps

Process Step 1

CC ID: 1140724

Fugro EarthData utilized commercial software as well as proprietary software for automatic filtering. The parameters used in the process were customized for each terrain type to obtain optimum results. Once the automated filtering was completed, the files were run through a visual inspection to ensure that the filtering was not too aggressive or not aggressive enough. In cases where the filtering was too aggressive and important terrain features were filtered out, the data was either run through a different filter or was corrected during the manual filtering process. Interactive editing was then completed in 3D visualization software which also provides manual and automatic point classification tools. Vegetation and artifacts remaining after automatic data post-processing were reclassified manually through interactive editing. The hard edges of ground features that were automatically filtered out during the automatic filtering process were brought back into ground class during manual editing. Auto-filtering routines were utilized as much as possible within fenced areas during interactive editing for efficiency. The technician reviewed the LiDAR points with color shaded TINs for anomalies in ground class during interactive filtering. Upon the completion of peer review and finalization of bare earth filtering, the classified LiDAR point cloud work tiles went through a water classification routine. Upon the completion of finalization of the classified LiDAR point cloud work tiles, the tiles were reprojected to NAD83 (HARN), UTM zone 18 north, meters; NAVD88, meters, using GEOID09 and cut to the approved tile layout in LAS format.

Process Date/Time: 2011-06-27 00:00:00

Process Step 2

CC ID: 1140725

The hydrographic features were collected as vector linework using classified LiDAR datasets, intensity images, shaded-relief TIN surfaces, and contours. These features were classified as Inland Ponds and Lakes, Inland Streams and Rivers (single line), Inland Streams and Rivers (double line), Non-Tidal Boundary Waters, and Tidal Waters. After initial collection, linework was then checked for the following topological and attribution rules: non-bank lines must be digitized from an uphill to downhill direction, lines must be attributed with the correct feature code, dangles must exist only at the upstream headwater end of streams and at the downstream outfall, line intersections must be at nodes, non-bankline features must form a dendritic collection network, lakes that have a digitized inflow path must have a centerline as well, lakes that have a digitized outflow path but do not have a digitized inflow path should not have a centerline, isolated ponds that are not part of the drainage network should not have centerlines; lake and stream banklines must form closed polygons, single streams should not fall within bankline polygons and lake and stream connector lines should not fall outside of bankline polygons. Hydro features were collected as vector linework using LiDAR and its derived products listed above. This linework is initially 2D, meaning that it does not have elevation values assigned to individual line vertices. Vertex elevation values were assigned using a distance weighted distribution of LiDAR points closest to each vertex. After the initial 'drape', the linework elevation values were further adjusted based on the following rules: lake feature vertices were re-assigned (flattened) to lowest draped vertex value; lake connector line vertices were re-assigned (flattened) to lowest draped vertex value of the surrounding lake bankline, single stream and stream connector line vertices were adjusted so that subsequent vertices are lower than previous ones based on line direction, and double stream bankline vertices were re-assigned based on the vertices of the closest adjusted double stream connector line. After assignment of 3D values, the stream network is checked to ensure the following does not exist: large differences between initial drape and adjusted elevation values, elevation differences between nodes, and elevation values flowing in an 'uphill' direction. Data was provided to the terrain department for hydro-enforcement of the DEM.

Process Date/Time: 2011-06-24 00:00:00

Process Step 3

CC ID: 1140726

NOAA OCM downloaded the data from Maryland iMAP as zip files by Block.

Process Date/Time: 2017-10-16 00:00:00
Process Contact: Office for Coastal Management (OCM)
Source: Lidar data from Maryland iMAP

Process Step 4

CC ID: 1140727

Lidar data were changed from NAVD88 (Geoid09) vertical coordinates to ellipsoid heights using the GEOID09 grids.

The class scheme was not described in the original metadata, but research on the related data for the Worcester coastal area suggests class 10 is ignored ground near breaklines and class 11 is withheld. Examination of the data supports that hypothesis.

Data were then ingested into the Digital Coast Data Access Viewer system for distribution.

Process Date/Time: 2018-02-26 00:00:00
Process Contact: Office for Coastal Management (OCM)

Acquisition Information


Instrument 1

CC ID: 1140728
Identifier: Leica ALS60
Instrument / Gear: Instrument
Instrument Type: lidar

Multipulse in air lidar sensor

Catalog Details

Catalog Item ID: 51633
GUID: gov.noaa.nmfs.inport:51633
Metadata Record Created By: Kirk Waters
Metadata Record Created: 2018-02-26 12:15+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