DredgeAreas
-10413742.739500
-8242851.506400
2959561.259300
4820731.571100
1
-
Relationship
-
DredgeAreasHaveLeaseDocs
Relationship
-
DredgeHasFinalReport
Relationship
-
DredgeHaveExposure
Relationship
-
DredgeHasLeaseDoc
Relationship
-
DredgeHasFinalReport
Relationship
002
Projected
GCS_WGS_1984
Linear Unit: Meter (1.000000)
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WGS_1984_Web_Mercator_Auxiliary_Sphere
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54B29768-EB93-4D42-BE88-0134D900BE04
dataset
Oceanographer
U.S. Department of Interior, Bureau of Ocean Energy Management, Marine Minerals Program
703-787-1747
marineminerals@boem.gov
45600 Woodland Road, VAM-LD
Sterling
VA
20166
US
Monday through Friday 8:00 AM to 5:00 PM (Eastern Time)
http://www.boem.gov/Marine-Minerals-Program
http://www.boem.gov/Marine-Minerals-Program
HyperText Protocol
web browser
BOEM MMIS website
Monday through Friday 8:00 AM to 5:00 PM (Eastern Time)
20241001
https://geoseas.geoplatform.gov/hosting/rest/services/MMP
ArcGIS 10.8.1
Enterprise Geodatabase Feature Class
2024-10-01T00:00:00
U.S. Department of Interior, Bureau of Ocean Energy Management, Marine Minerals Program
marineminerals@boem.gov
45600 Woodland Road, VAM-LD
Sterling
VA
20166
US
http://www.boem.gov/Marine-Minerals-Program
HyperText Protocol
web browser
BOEM MMIS website
Monday through Friday 8:00 AM to 5:00 PM (Eastern Time)
U.S. Department of Interior, Bureau of Ocean Energy Management, Marine Minerals Program
vector digital data
DredgeAreas
<DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN>Dredge area polygons represent the approximate lateral extent of where dredging of outer continental shelf (OCS) sediment has occurred within authorized OCS lease areas, which are maintained by the Bureau of Ocean Energy Management (BOEM), part of the U.S. Department of the Interior. The dredged material (e.g. sediment) is typically transported via pipeline and deposited along the shoreline of a pre-determined coastal area needing nourishment. Entities are authorized to dredge sand, gravel, or shell resources from the OCS after entering into a Negotiated Non-Competitive Lease or Memorandum of Agreement with BOEM. Section 8 (k) of the OCS Lands Act (OCSLA), as amended by Public Law 103-426 (enacted in 1994), gives BOEM the authority to negotiate an agreement for the use of OCS sand, gravel, and shell resources for use in: (1) a project for shore protection, beach restoration, or coastal restoration undertaken by a Federal, State, or local government agency; or (2) for use in a construction project funded in whole or part by or authorized by the Federal government. This dataset is a collection of dredge areas under BOEM's purview. Attribution consists of state, OCS lease number, project ID, borrow area ID, construction (dredging) start and end dates, dredged volume, and delineation quality; see attribute definitions for full explanations. This dataset will be updated as new data are received from lessees.</SPAN></P></DIV></DIV></DIV>
The dredge areas feature class serves as a geospatial record of where individual dredge events have occurred within OCS borrow areas authorized for use by the Bureau of Ocean Energy Management (BOEM), part of the U.S. Department of the Interior. The footprint of each polygon represents the approximate lateral extent of changes to the seabed (increased depth) that have occurred directly as a result of dredging. Each polygon is delineated based on analysis and interpretation of before- and after-dredge bathymetric data, the computed bathymetric surface difference (e.g., the output surface resulting from subtracting after-dredge bathymetric data from before-data bathymetric data over an equally-sized grid). The analysis of these data enables BOEM to monitor and quantify natural and anthropogenic changes (e.g., dredged volume) to the seabed in OCS borrow areas, which facilitates comprehensive resource management and conservation. Entities are authorized to dredge sand, gravel, or shell resources from the OCS after entering into a Negotiated Non-Competitive Lease or Memorandum of Agreement with BOEM. Section 8 (k) of the OCS Lands Act (OCSLA), as amended by Public Law 103-426 (enacted in 1994), gives BOEM the authority to negotiate an agreement for the use of OCS sand, gravel, and shell resources for use in: (1) a project for shore protection, beach restoration, or coastal restoration undertaken by a Federal, State, or local government agency; or (2) for use in a construction project funded in whole or part by or authorized by the Federal government. This dataset is a collection of dredge areas under BOEM's purview. Attribution consists of state, OCS lease number, project ID, borrow area ID, construction (dredging) start and end dates, approximate dredged volume, and delineation quality; see attribute definitions for full explanations of how individual fields are calculated (if applicable). This dataset will be updated as new data are received from lessees.
NASA/GCMD Location Keywords
2021-01-26T00:00:00
GULF OF MEXICO
ATLANTIC OCEAN
GLOBAL OCEAN
NORTH ATLANTIC OCEAN
SEA FLOOR
Outer Continental Shelf
U.S. Department of Commerce, 1995, Countries, dependencies, areas of special sovereignty, and their principal administrative divisions, Federal Information Processing Standard (FIPS) 10-4): Washington, D.C., National Institute of Standards and Technology.
1995-01-01T00:00:00
US
Library of Congress Subject Headings
2021-03-01T00:00:00
Geology
This data is in the public domain and has no access restrictions.
FIPS 199 Security Classification
There are no restrictions; the data is releasable to the public.
<DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN>The Bureau of Ocean Energy Management (BOEM) provides the data for use "as is". BOEM provides this information with the understanding that it is not guaranteed to be accurate, correct or complete and conclusions drawn from such information are the responsibility of the user. While every effort has been made to ensure the accuracy, correctness and timeliness of materials presented within the limits of the current state of the art, BOEM assumes no responsibility for errors or omissions, nor as a result of the failure of the data to function on a particular system. BOEM makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty. Users are cautioned to consider carefully the provisional nature of these data and information before using them for decisions that concern personal or public safety or the conduct of business that involves substantial monetary or operational consequences. Conclusions drawn from or actions undertaken on the basis of, such data and information are the sole responsibility of the user. The maps shown here are for illustration and planning purposes only and are not suitable for site-specific decision making. The data are not suitable for navigational purposes. Information found here should not be used for making financial or any other commitments. This data was developed by the U.S. Government; no other proprietary rights may be attached to them nor may they be sold to the U.S. Government as part of any procurement of products or services. Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the Bureau of Ocean Energy Management (BOEM) as the source of this information.</SPAN></P></DIV></DIV></DIV>
-93.548236
-75.193337
25.680481
37.857258
publication date
2021-07-23T00:00:00
2024-10-01T00:00:00
Source (bathymetric) data are available upon request. The most current version of this dataset can be downloaded via the Marine Minerals Information System (MMIS) viewer at https://mmis.boem.gov.
Maine
Maryland
Massachusetts
Florida
Rhode Island
New Jersey
Georgia
North Carolina
Virginia
Delaware
South Carolina
New York
ATLANTIC OCEAN
Geology
Geophysical
Marine Mineral Resources
Sediment
Survey
Non-Energy
Sand Resources
Offshore
Sand
Outer Continental Shelf
Cubic Yards
Physical Habitats
OCS
Mining and Mineral Extraction
Dredging
Gravel
US
GULF OF MEXICO
NORTH ATLANTIC OCEAN
SEA FLOOR
Oceans
Lease
Sand
Mineral Resources
Geophysical Survey
Non-Energy
Dredging
Shoal
Bathymetric Survey
Beach Nourishment
Authorized Lease
Benthic
Oceanographic Sensors
Offshore
Physical Oceanography
Dredge Volume
Oceanographer
U.S. Department of Interior, Bureau of Ocean Energy Management, Marine Minerals Program
703-787-1747
marineminerals@boem.gov
45600 Woodland Road, VAM-LD
Sterling
VA
20166
US
Monday through Friday 8:00 AM to 5:00 PM (Eastern Time)
http://www.boem.gov/Marine-Minerals-Program
http://www.boem.gov/Marine-Minerals-Program
HyperText Protocol
web browser
BOEM MMIS website
Monday through Friday 8:00 AM to 5:00 PM (Eastern Time)
U.S. Department of Interior, Bureau of Ocean Energy Management, Marine Minerals Program
Esri ArcPro
1
-93.548243
-74.046795
39.688174
25.680486
2026-01-01T00:00:00
The MMIS data model utilizes a hierarchical structure where an ESRI enterprise geodatabase represents the top tier, and feature datasets and raster catalogs are the secondary tiers which contain groupings of similar data layers. These individual data layers were identified by MMP as important, and they make up the bottom tier. Most individual vector layers and tables are collections of data from multiple sources and across multiple dates. Extensive research went into the construction of (1) the hierarchical groupings of data (primarily by subject matter and file format) and (2) technical aspects of the data model. Data within the geodatabase was consolidated to reduce redundancy, resulting in several stand-alone tables. Relationship classes utilizing global IDs were built between vector layers and stand-alone tables in order to link disparate data. The entire MMIS data model was originally constructed using ESRI ArcGIS Diagrammer, a tool that creates and edits a geodatabase schema. The resulting geodatabase structure, data, and relationship classes were reviewed thoroughly by multiple individuals using ESRI Geodatabase Diagrammer Add-In, ESRI ArcGIS, and Microsoft Visio. ESRI Geodatabase Diagrammer Add-In creates a detailed break-down of the geodatabase and a Visio data model poster.
Conceptual consistency: adherence to rules of the conceptual schema
The MMIS data model utilizes a hierarchical structure where an ESRI enterprise geodatabase represents the top tier, and feature datasets and raster catalogs are the secondary tiers which contain groupings of similar data layers. These individual data layers were identified by MMP as important, and they make up the bottom tier. Most individual vector layers and tables are collections of data from multiple sources and across multiple dates. Extensive research went into the construction of (1) the hierarchical groupings of data (primarily by subject matter and file format) and (2) technical aspects of the data model. Data within the geodatabase was consolidated to reduce redundancy, resulting in several stand-alone tables. Relationship classes utilizing global IDs were built between vector layers and stand-alone tables in order to link disparate data. The entire MMIS data model was originally constructed using ESRI ArcGIS Diagrammer, a tool that creates and edits a geodatabase schema. The resulting geodatabase structure, data, and relationship classes were reviewed thoroughly by multiple individuals using ESRI Geodatabase Diagrammer Add-In, ESRI ArcGIS, and Microsoft Visio. ESRI Geodatabase Diagrammer Add-In creates a detailed break-down of the geodatabase and a Visio data model poster.
The spatial data and attribute tables loaded into the MMIS data model are believed to be complete, in regards to maintaining each data layer/table after retrieving it from its source. Please refer to the scientific reports, as well as BOEM MMP Leases, negotiated agreements, Memoranda of Agreements, and project completion reports, for discussions of the results on the corresponding source data. Most individual vector layers and tables in the MMIS data model are collections of data from multiple sources and across multiple dates. Most likely, these MMIS layers/tables will continue to have more data loaded in the future, therefore expanding upon the list of sources and dates. Additionally, the Pacific Outer Continental Shelf (OCS) and Alaska OCS regions may eventually be added to the data model, aside from the Atlantic and Gulf of Mexico OCS regions.
Completeness omission: data absent from the dataset, as described by the scope
The spatial data and attribute tables loaded into the MMIS data model are believed to be complete, in regards to maintaining each data layer/table after retrieving it from its source. Please refer to the scientific reports, as well as BOEM MMP Leases, negotiated agreements, Memoranda of Agreements, and project completion reports, for discussions of the results on the corresponding source data. Most individual vector layers and tables in the MMIS data model are collections of data from multiple sources and across multiple dates. Most likely, these MMIS layers/tables will continue to have more data loaded in the future, therefore expanding upon the list of sources and dates. Additionally, the Pacific Outer Continental Shelf (OCS) and Alaska OCS regions may eventually be added to the data model, aside from the Atlantic and Gulf of Mexico OCS regions.
Please refer to the scientific reports, as well as Bureau of Ocean Energy Management (BOEM) Marine Minerals Program (MMP) Leases, negotiated agreements, cooperative agreements, Memoranda of Agreements, and project completion reports, for accuracy statements on the corresponding source data. These documents are referenced in the attribute tables, where appropriate. In regards to attribute assignment in the Marine Minerals Information Systems (MMIS) data model, every effort was made to load source data into MMIS without error or modification. Some attributes contain domain restrictions in an effort to standardize the field entries and to decrease potential inconsistent entries (e.g., spelling, grammar, typographical errors, and subject matter) in the attribute.
Quantitative attribute accuracy: accuracy of quantitative attributes
Please refer to the scientific reports, as well as Bureau of Ocean Energy Management (BOEM) Marine Minerals Program (MMP) Leases, negotiated agreements, cooperative agreements, Memoranda of Agreements, and project completion reports, for accuracy statements on the corresponding source data. These documents are referenced in the attribute tables, where appropriate. In regards to attribute assignment in the Marine Minerals Information Systems (MMIS) data model, every effort was made to load source data into MMIS without error or modification. Some attributes contain domain restrictions in an effort to standardize the field entries and to decrease potential inconsistent entries (e.g., spelling, grammar, typographical errors, and subject matter) in the attribute.
unknown
Absolute external positional accuracy: closeness of reported coordinate values to values accepted as or being true
Absolute external positional accuracy: closeness of reported coordinate values to values accepted as or being true
Absolute external positional accuracy: closeness of reported coordinate values to values accepted as or being true
unknown
Absolute external positional accuracy: closeness of reported coordinate values to values accepted as or being true
Absolute external positional accuracy: closeness of reported coordinate values to values accepted as or being true
Absolute external positional accuracy: closeness of reported coordinate values to values accepted as or being true
Attribute data were collected from lease documents provided by lessees. Source data used to delineate the approximate extent of dredging were also provided by the lessees. These data were utilized by BOEM to produce the dredge areas features.
BOEM Archives
BOEM Archives
2024-10-01T00:00:00
U.S. Department of Interior, Bureau of Ocean Energy Management, Marine Minerals Program
Multiple investigators and projects
document
publication date
1995-05-17T00:00:00
2024-10-01T00:00:00
The spatial and tabular data presented in this dataset were identified by the Bureau of Ocean Energy Management (BOEM) Marine Minerals Program (MMP) for the MMIS project as being critical for MMP's decision making and management responsibilities of Federal Outer Continental Shelf (OCS) mineral exploration and Federal non-energy sand/gravel lease activities. All OCS marine mineral lessees are required to submit pre- and post-dredge bathymetric data, which are then analyzed by BOEM staff to verify the reported material extraction volumes, that dredging solely occurred within the authorized lease area boundaries, and to gain an understanding of seabed dynamics within borrow and the surrounding vicinity. The approximate lateral extent of dredging within each lease area was determined based on analysis and interpretation of before- and after-dredge bathymetric data, the computed bathymetric surface difference between each survey, and or operational dredge plant data.A polygon representing the approximate extent of dredging was manually digitized around the area disturbed (generally where depth has increased) directly as a result of dredge activity. Later, a master layer was created in the MMIS geodatabase data model to house all dredge area polygons in a single feature class (reprojected into the NAD83 geodetic reference system). A list of attributes was developed including the corresponding lease number, the borrow area ID (e.g. Shoal A), construction (dredging) start and ends dates, calculated and reported dredge volume in cubic yards, and a qualitative description of the accuracy of the delineated dredge area (partially based on the pixel resolution). Attribute data were collected from lease documents, post construction reports, survey reports, and survey data. Next, the disparate dredge area shapefiles and their attribute data were loaded into the MMIS Dredge Areas feature class. For increased accessibility, each dredge area polygon was linked to the corresponding PDF lease document(s). For specific process information regarding acquisition, please reference the individual lease documents.
2024-10-01T00:00:00
69
EPSG
6.18.3(9.3.1.2)
True
True
Feature Catalogue for MMIS.SDE.DredgeAreas
2024-10-01T00:00:00
U.S. Department of Interior, Bureau of Ocean Energy Management, Marine Minerals Program
https://mmis.boem.gov
HyperText Protocol
web browser
Content Information for the Resource
Link to access information about the data content.
DredgeAreas
Enables BOEM to ensure dredge operations are within the lease boundaries. Quality is determined by the resolution of the pre and post survey data from which the polygon is delineated.
BOEM
Feature Class
69
BorrowArea
Borrow Area Identifier Name (e.g. Shoal A)
BOEM
Borrow Area Identifier Name (e.g. Shoal A)
Borrow Area ID
String
50
0
0
OBJECTID
Internal feature number
Esri
Internal feature number
OBJECTID
OID
4
10
0
LeaseNo
BOEM Lease Agreement Number
BOEM
BOEM Lease Agreement Number
Lease Number
String
50
0
0
DredgeVolRep
Amount of sand dredged in cubic yards as reported in the Project Completion Report
BOEM
Amount of sand dredged in cubic yards as reported in the Project Completion Report
Dredge Volume Reported
Double
8
38
8
SHAPE
Feature geometry
Esri
Feature geometry
SHAPE
Geometry
8
0
0
RuleID
Assigns Cartographic Representation
Esri
1
Dredge Areas
BOEM
-1
Free Representation
BOEM
RuleID
Integer
4
10
0
ConstructionStart
The date construction (dredging) started.
BOEM
The date construction (dredging) started.
Construction Start Date
Date
8
0
0
Dredge_GlobalLeaseID
Unique identifier that links feature to lease documents
BOEM
Unique identifier that links feature to lease documents
Global Lease ID
GUID
38
0
0
DredgeVolCalc
Amount of sand dredged in cubic yards as calculated within the lease area by computing the volume change between pre- and post-dredge survey bathymetric data. This volume is derived from the grid volume report generated as an output when using the calculate volume command in Golden Software's Surfer program. In most cases, the dredge volume calculated field of this feature class is populated with the positive cut volume in the output grid volume report (converted to cubic yards). This value is representative of volume loss in the borrow area due to dredging and is valid under two main assumptions: (1) an otherwise static seabed in the intervening time period and (2) acceptable vertical survey error tolerances (e.g., +/- 0.1 feet minimum vertical survey accuracy over a 1 square mile (640 acres) survey area translates to a minimum uncertainty of at least +/- 103,000 cubic yards). However, there are many factors (e.g., source data quality/vertical uncertainty, time between dredge surveys, timing of surveys relative to dredging, significant natural sediment mobilization, method of calculation, missing information or context, etc.; ) that can result in discrepancies between calculating dredge volume based on positive cut volume using the method described above and the dredge volume reported (or calculated) by the Lessee or their contractors. Thus, if the positive cut volume is a significant deviation from the expected result (based on static seabed assumption and approximate vertical uncertainty across the borrow area) and is deemed an invalid representation of dredge volume, then an alternative method of analysis may be required to calculate a value representative of volume loss directly due to dredging. In these situations, supporting notes and explanation have been added in the Comments attribute field to provide as much context as possible within the allotted character limit. If the dredged volume cannot be determined with reasonable confidence, then no value is reported in the dredge volume calculated field.
BOEM
Amount of sand dredged in cubic yards as calculated within the lease area by computing the volume change between pre- and post-dredge survey bathymetric data. This volume is derived from the grid volume report generated as an output when using the calculate volume command in Golden Software's Surfer program. In most cases, the dredge volume calculated field of this feature class is populated with the positive cut volume in the output grid volume report (converted to cubic yards). This value is representative of volume loss in the borrow area due to dredging and is valid under two main assumptions: (1) an otherwise static seabed in the intervening time period and (2) acceptable vertical survey error tolerances (e.g., +/- 0.1 feet minimum vertical survey accuracy over a 1 square mile (640 acres) survey area translates to a minimum uncertainty of at least +/- 103,000 cubic yards). However, there are many factors (e.g., source data quality/vertical uncertainty, time between dredge surveys, timing of surveys relative to dredging, significant natural sediment mobilization, method of calculation, missing information or context, etc.; ) that can result in discrepancies between calculating dredge volume based on positive cut volume using the method described above and the dredge volume reported (or calculated) by the Lessee or their contractors. Thus, if the positive cut volume is a significant deviation from the expected result (based on static seabed assumption and approximate vertical uncertainty across the borrow area) and is deemed an invalid representation of dredge volume, then an alternative method of analysis may be required to calculate a value representative of volume loss directly due to dredging. In these situations, supporting notes and explanation have been added in the Comments attribute field to provide as much context as possible within the allotted character limit. If the dredged volume cannot be determined with reasonable confidence, then no value is reported in the dredge volume calculated field.
Dredge Volume Calculated
Double
8
38
8
State
Location relative to closest state; state funded for OCS study, two letter postal code
BOEM
Location relative to closest state; state funded for OCS study, two letter postal code
State
String
2
0
0
SHAPE.STLength()
Length of feature in internal units
Esri
Length of feature in internal units
SHAPE.STLength()
Double
0
0
0
Dredge_GlobalReportID
Unique identifier that links feature to post-construction Report
BOEM
Unique identifier that links feature to post-construction Report
Global Report ID
GUID
38
0
0
Quality
Qualitative description of the accuracy of the dredge area delineation. This metric largely relies on resolution of survey data used in the delineation, where higher resolution surveys usually result in better delineations.
BOEM
Fair
Fair - 10-50ft
BOEM
Poor
Poor - > 50ft
BOEM
Good
Good - < 10ft
BOEM
Delineation Quality
String
10
0
0
ProjectID
General project name associated with lease; county, locality, or project name followed by fiscal year of original lease execution (e.g. Brevard County 2005)
BOEM
General project name associated with lease; county, locality, or project name followed by fiscal year of original lease execution (e.g. Brevard County 2005)
Project ID
String
50
0
0
SHAPE.STArea()
Area of feature in internal units squared
Esri
Area of feature in internal units squared
SHAPE.STArea()
Double
0
0
0
ConstructionComplete
The date construction (dredging) ended.
BOEM
The date construction (dredging) ended expressed as MM\DD\YYYY
Construction Complete Date
Date
8
0
0
Comments
Additional comments or notes containg supporting information
BOEM
Additional comments or notes containg supporting information
Comments
String
250
0
0
Override
Overrides Cartographic Representation
Esri
Overrides Cartographic Representation
Override
Blob
0
0
0
created_user
created_user
Stores the name of the user who creates features or records
Esri
Text
255
Read-only. Stores the name of the user who creates features or records
0
0
created_date
created_date
Stores the date and time a feature or record was created
Esri
Date
8
Read-only. Stores the date and time a feature or record was created
0
0
last_edited_user
last_edited_user
Stores the name of the user who last edited a feature or record
Esri
Text
255
Read-only. Stores the name of the user who last edited a feature or record
0
0
last_edited_date
last_edited_date
Stores the date a feature or record was last edited
Esri
Date
8
Read-only. Stores the date a feature or record was last edited
0
0
The Federal Outer Continental Shelf (OCS) Dredge Area feature class serves as a geospatial record of where individual dredge events have occurred within OCS borrow areas authorized for use by the Bureau of Ocean Energy Management (BOEM), part of the U.S. Department of the Interior. The footprint of each polygon represents the approximate lateral extent of changes to the seabed (increased depth) that have occurred directly as a result of dreding. Each polygon is delineated based on analysis and interpretation of before- and after-dredge bathymetric data and the computed surface difference (e.g., the output surface resulting from subtracting after-dredge bathymetric data from before-data bathymetric data over an equally-sized grid). The analysis of these data enables BOEM to monitor and quantify natural and anthropogenic changes (e.g., dredged volume) to the seabed in OCS borrow areas, which facilitates comprehensive resource management and conservation. Polygon quality is partially dependent on the resolution of the pre- and post- dredge bathymetric survey data.
BOEM
Simple
FALSE
69
TRUE
FALSE