Gulf of Mexico NAD83 Cadastral Data

Geographic Information System (GIS) Data and Maps

The Geospatial Services Division performs mathematical offshore boundary location computations and prepares Official Protraction Diagrams (OPDs) and Official Protraction Aliquot Diagrams (OPADs) depicting OCS Block and Aliquot information, the Submerged Lands Act Boundary, Limit of "8(g)/8(p) Zone", Marine Protected Areas and Maritime Boundaries.

NOTE: Gulf of Mexico Region OPDs that show the Submerged Lands Act and Section 8(g)/8(p) Zone boundaries do not reflect recent shoreline changes. These boundaries were permanently immobilized (“fixed”) by actions of the Supreme Court for Louisiana (1981), Mississippi (1990), Alabama (1993), and Texas (1998). Accordingly, the shoreline associated with these boundaries as shown on the OPDs has not been updated. At this time, BOEM has completed the Gulf of Mexico NAD83 Cadastre for the extent of the Renewable Energy Call Area.

OPD and OPAD Images

A standard OPD/OPAD is 1 degree in latitude by 2 degrees in longitude (at lower latitudes: 0 - 48 degrees). At higher latitudes (48 - 75 degrees) such as Alaska and northern Washington, OPDs/OPADs are 3 degrees wide. OPD/OPAD limits usually approximate the standard 1:250,000 scale U.S. Geological Survey topographic map series. The OPDs/OPADs are numbered using the United Nations International Map of the World Numbering System. OPD/OPAD names usually coincide with standard topographic sheet names when diagrams include land areas. OPD/OPAD sheet names relate to either land features or to hydrographic features contained within the limits of the diagram. Shoreline planimetric detail is shown when it falls within the limits of a diagram.

Listed in the table below are Provisional OPDs and OPADs available in PDF format.

NOTE: SOBDs are not currently available for download. BOEM intends to make the SOBDs available for download in March 2023 following the publishing of the first edition OPDs/OPADs.

Scroll down the page to access individual Provisional OPDs and OPADs available in PDF format.

Individual Gulf of Mexico Region NAD83 OPDs and OPADs

OPD Name

OPD Files

OPAD Files

Gulf of Mexico Region OPD Index

GOM83 OPDlndex.pdf

Gulf of Mexico OPDs PDF File Bundle

GOM83 OPDs.zip

Gulf of Mexico OPAD PDF File Bundle

GOM83-OPADs.zip

NG14-09
Brownsville

NG14-09-01-Jun-2022.pdf

NG14-09-01-Jun-2022-OPAD.pdf

NG14-06
Port Isabel

NG14-06-01-Jun-2022.pdf

NG14-06-01-Jun-2022-OPAD.pdf

NG14-03
Corpus Christi

NG14-03-01-Jun-2022.pdf

NG14-03-01-1UN-2022-OPAD.pdf

NH14-12
Beeville

NH14-12-01-Jun-2022.pdf

NH14-12-01-Jun-2022-OPAD.pdf

NG15-01
East Breaks

NG15-01-01-Jun-2022.pdf

NG15-01-01-Jun-2022-OPAD.pdf

NG15-02
Garden Banks

NG15-02-01-Jun-2022.pdf

NG15-02-01-Jun-2022-OPAD.pdf

NG15-03
Green Canyon

NG15-03-01-Jun-2022.pdf

NG15-03-01-Jun-2022-OPAD.pdf

NH15-10
Bay City

NH15-10-01-Jun-2022.pdf

NH15-10-01-Jun-2022-OPAD.pdf

NH15-11
Bouma Bank

NH15-11-01-Jun-2022.pdf

NH15-11-01-Jun-2022-OPAD.pdf

NH15-12
Ewing Bank

NH15-12-01-Jun-2022.pdf

NH15-12-01-Jun-2022-OPAD.pdf

NH15-07
Houston

NH15-07-01-Jun-2022.pdf

NH15-07-01-Jun-2022-OPAD.pdf

NH15-08
Port Arthur

NH15-08-01-Jun-2022.pdf

NH15-08-01-Jun-2022-OPAD.pdf

NH15-09
New Orleans

NH15-09-01-Jun-2022.pdf

NH15-09-01-Jun-2022-OPAD.pdf

NH16-10
Mississippi Canyon

NH16-10-01-Jun-2022.pdf

NH16-10-01-Jun-2022-OPAD.pdf

NH16-07
Viosca Knoll

NH16-07-01-Jun-2022.pdf

NH16-07-01-Jun-2022-OPAD.pdf

GIS Files

The various cadastre data is offered as a static file geodatabase . The Gulf of Mexico NAD83 Regional File Geodatabase can be viewed using ArcGIS or a variety of other GIS systems. 

NOTE: The precise coordinates of a GIS file can be altered slightly by various GIS functions. Consequently, these GIS files are not an Official Record for BOEM offshore boundaries. Only the coordinates shown on Official OPDs constitute an Official Record for offshore coordinate values.