(Version 4.1, updated September 13, 2013) Maritime limits for the United States are measured from the U.S. baseline, recognized as the low-water line along the coast as marked on NOAA's nautical charts in accordance with the articles of the Law of the Sea. The baseline and related maritime limits are reviewed and approved by the interagency U.S. Baseline Committee. The primary purpose of this dataset is to update the official depiction of these maritime limits and boundaries on NOAA's nautical charts. The Office of Coast Survey depicts on its nautical charts the territorial sea (12 nautical miles), contiguous zone (24nm), and exclusive economic zone (200nm, plus maritime boundaries with adjacent/opposite countries). U.S. maritime limits are ambulatory and subject to revision based on accretion or erosion of the charted low water line. For more information about U.S. Maritime Limits and Boundaries and to stay up-to-date, see: http://www.nauticalcharts.noaa.gov/csdl/mbound.htm. For the full FGDC metadata record, see: http:www.ncddc.noaa.gov/approved_recs/nos_de/ocs/ocs/MB_ParentDataset.html. Coordinates for the US/Canada international boundary, on land and through the Great Lakes, are managed by the International Boundary Commission.

The maritime limits and boundaries of the U.S., found in the A-16 National Geospatial Data Asset Portfolio, is recognized as the low-water line along the coast measured from the U.S. baseline. This is marked on official U.S. nautical charts in accordance with the articles of the Law of the Sea. The baseline and related maritime limits are reviewed and approved by the inter-agency U.S. Baseline Committee.The primary purpose of this data is to update the official depiction of these maritime limits and boundaries on the National Oceanic and Atmospheric Administration's nautical charts. The Office of Coast Survey depicts on its nautical charts the territorial sea (12 nautical miles), contiguous zone (24 nautical miles), and Exclusive Economic Zone (200 nautical miles, plus maritime boundaries with adjacent/opposite countries). U.S. maritime limits are ambulatory and are subject to revision based on accretion or erosion of the charted low-water line. For more information about U.S. maritime limits and boundaries and to download data, see U.S. Maritime Limits & Boundaries. For the full Federal Geographic Data Committee metadata record, see Maritime Limits and Boundaries of United States of America.Thumbnail source image courtesy of: David Restivo

NOAA is responsible for depicting on its nautical charts the limits of the 12 nautical mile Territorial Sea, 24 nautical mile Contiguous Zone, and 200 nautical mile Exclusive Economic Zone (EEZ). The outer limit of each of these zones is measured from the U.S. normal baseline, which coincides with the low water line depicted on NOAA charts and includes closing lines across the entrances of legal bays and rivers, consistent with international law. The U.S. baseline and associated maritime limits are reviewed and approved through the interagency U.S. Baseline Committee, which is chaired by the U.S. Department of State. The Committee serves the function of gaining interagency consensus on the proper location of the baseline using the provisions of the 1958 Convention on the Territorial Sea and the Contiguous Zone, to ensure that the seaward extent of U.S. maritime zones do not exceed the breadth that is permitted by international law. In 2002 and in response to mounting requests for digital maritime zones, NOAA launched a project to re-evaluate the U.S. baseline in partnership with other federal agencies via the U.S. Baseline Committee. The focus of the baseline evaluation was NOAA's largest scale, most recent edition nautical charts as well as supplemental source materials for verification of certain charted features. This dataset is a result of the 2002-present initiative and reflects a multi-year iterative project whereby the baseline and associated maritime limits were re-evaluated on a state or regional basis. In addition to the U.S. maritime limits, the U.S. maritime boundaries with opposite or adjacent countries as well as the US/Canada International Boundary (on land and through the Great Lakes) are also included in this dataset.

The Digital Geologic Map of International Boundary and Water Commission Mapping in Amistad National Recreation Area, Texas and Mexico is composed of GIS data layers complete with ArcMap 9.3 layer (.LYR) files, two ancillary GIS tables, a Map PDF document with ancillary map text, figures and tables, a FGDC metadata record and a 9.3 ArcMap (.MXD) Document that displays the digital map in 9.3 ArcGIS. The data were completed as a component of the Geologic Resources Inventory (GRI) program, a National Park Service (NPS) Inventory and Monitoring (I&M) funded program that is administered by the NPS Geologic Resources Division (GRD). Source geologic maps and data used to complete this GRI digital dataset were provided by the following: Eddie Collins, Amanda Masterson and Tom Tremblay (Texas Bureau of Economic Geology); Rick Page (U.S. Geological Survey); Gilbert Anaya (International Boundary and Water Commission). Detailed information concerning the sources used and their contribution the GRI product are listed in the Source Citation sections(s) of this metadata record (ibwc_metadata.txt; available at http://nrdata.nps.gov/amis/nrdata/geology/gis/ibwc_metadata.xml). All GIS and ancillary tables were produced as per the NPS GRI Geology-GIS Geodatabase Data Model v. 2.1. (available at: http://science.nature.nps.gov/im/inventory/geology/GeologyGISDataModel.cfm). The GIS data is available as a 9.3 personal geodatabase (ibwc_geology.mdb), and as shapefile (.SHP) and DBASEIV (.DBF) table files. The GIS data projection is NAD83, UTM Zone 14N. The data is within the area of interest of Amistad National Recreation Area.

The Territorial Sea of the United States of America By the President of the United States of America A Proclamation of 27 December 1988 states the extension of the territorial sea of the United States of America, the Commonwealth of Puerto Rico, Guam, American Samoa, the United States Virgin Islands, the Commonwealth of the Northern Mariana Islands, and any other territory or possession over which the United States exercises sovereignty.

The territorial sea of the United States henceforth extends to 12 nautical miles from the baselines of the United States determined in accordance with international law. In accordance with international law, as reflected in the applicable provisions of the 1982 Convention on the Law of the Sea, within the territorial sea of the United States, the ships of all countries enjoy the right of innocent passage and the ships and aircraft of all countries enjoy the right of transit passage through international straits. Nothing in this Proclamation: (a) extends or otherwise alters existing federal or State law or any jurisdiction, rights, legal interests, or obligations derived therefrom, or (b) impairs the determination, in accordance with international law, of any maritime boundary of the United States with a foreign jurisdiction.

https://www.un.org/depts/los/LEGISLATIONANDTREATIES/PDFFILES/USA_1988_Proclamation.pdf

Contained within the 1st Edition (1906) of the Atlas of Canada is a plate that shows five maps illustrating international and interprovincial boundary claims. Two show the Quebec - New Brunswick - Maine area, and another displays the Canada - Labrador boundary. There are two small maps showing offshore claims; one for the Bay of Fundy, and the other for the Gulf Islands (San Juan) in the Strait of Georgia. The Eastern Canada- United States boundary was commonly called the 'Marine boundary' from 1783 to 1842. There were still many disputes going on at the time, including jurisdiction of Newfoundland, the province of New Brunswick - Quebec and the United States, as well as Vancouver Island. The boundary indicating the Labrador coast was to be claimed by Canada. In addition, major railway systems displayed.

This data set contains the geographic place names for features in the U.S territorial waters and outer continental shelf. These names can be used to find or define a general location. The primary sources for this dataset include the NOAA Electronic Navigational Charts. Different marine place names are displayed depending on the scale you are zoomed into on the map.

© marinecadastre.gov This layer is a component of Marine Place Names.

MarineCadastre.gov map service displaying marine feature place names.

This map service presents spatial information about MarineCadastre.gov services across the United States and Territories in the Web Mercator projection. The service was developed by the National Oceanic and Atmospheric Administration (NOAA), but may contain data and information from a variety of data sources, including non-NOAA data. NOAA provides the information “as-is” and shall incur no responsibility or liability as to the completeness or accuracy of this information. NOAA assumes no responsibility arising from the use of this information. The NOAA Office for Coastal Management will make every effort to provide continual access to this service but it may need to be taken down during routine IT maintenance or in case of an emergency. If you plan to ingest this service into your own application and would like to be informed about planned and unplanned service outages or changes to existing services, please register for our Data Services Newsletter (http://coast.noaa.gov/digitalcoast/publications/subscribe). For additional information, please contact the NOAA Office for Coastal Management (coastal.info@noaa.gov).

© MarineCadastre.gov

U.S. collision regulation boundaries are lines of demarcation delineating those waters upon which mariners shall comply with the International Regulations for Preventing Collisions at Sea, 1972 (72 COLREGS) and those waters upon which mariners shall comply with the Inland Navigation Rules. The waters inland of these lines are subject to the Inland Navigation Rules Act of 1980. The waters outside these lines are subject to the International Navigation Rules of the International Regulations for Preventing Collisions at Sea, 1972 (COLREGS). The Coast Guard has the legal authority to effect regulatory changes to COLREGS. Creation of features was interpreted from descriptions published in the Code of Federal Regulations Title 33, Part 80.

© MarineCadastre.gov This layer is a component of Navigation and Marine Transportation.

Marine Cadastre themed service for public consumption featuring layers associated with navigation and marine transportation.

This map service presents spatial information about MarineCadastre.gov services across the United States and Territories in the Web Mercator projection. The service was developed by the National Oceanic and Atmospheric Administration (NOAA), but may contain data and information from a variety of data sources, including non-NOAA data. NOAA provides the information “as-is” and shall incur no responsibility or liability as to the completeness or accuracy of this information. NOAA assumes no responsibility arising from the use of this information. The NOAA Office for Coastal Management will make every effort to provide continual access to this service but it may need to be taken down during routine IT maintenance or in case of an emergency. If you plan to ingest this service into your own application and would like to be informed about planned and unplanned service outages or changes to existing services, please register for our Data Services Newsletter (http://coast.noaa.gov/digitalcoast/publications/subscribe). For additional information, please contact the NOAA Office for Coastal Management (coastal.info@noaa.gov).

© MarineCadastre.gov

This shapefile provides a worldwide geographic division by merging the World Continents division proposed by Esri Data and Maps (2024) to the Global Oceans and Seas version 1 division proposed by the Flanders Marine Institute (2021). Though divisions of continents and oceans/seas are available, the combination of both in a single shapefile is scarce.

The Continents and Oceans/Seas shapefile was carefully processed to remove overlaps between the inputs, and to fill gaps (i.e., areas with no information) by spatially joining these gaps to neighbour polygons. In total, the original world continents input divides land areas into 8 categories (Africa, Antarctica, Asia, Australia, Europe, North America, Oceania, and South America), while the original oceans/seas input divides the oceans/seas into 10 categories (Arctic Ocean, Baltic Sea, Indian Ocean, Mediterranean Region, North Atlantic Ocean, North Pacific Ocean, South Atlantic Ocean, South China and Easter Archipelagic Seas, South Pacific Ocean, and Southern Ocean). Therefore, the resulting world geographic division has 18 possible categories.

References

Esri Data and Maps (2024). World Continents. Available online at https://hub.arcgis.com/datasets/esri::world-continents/about. Accessed on 05 March 2024.

Flanders Marine Institute (2021). Global Oceans and Seas, version 1. Available online at https://www.marineregions.org/. https://doi.org/10.14284/542. Accessed on 04 March 2024.

Link to the ScienceBase Item Summary page for the item described by this metadata record. Service Protocol: Link to the ScienceBase Item Summary page for the item described by this metadata record. Application Profile: Web Browser. Link Function: information

Vessel traffic data, or Automatic Identification System (AIS) data, are collected by the U.S. Coast Guard through an onboard navigation safety device that transmits and monitors the location and characteristics of vessels in U.S. and international waters in real time. The Bureau of Ocean Energy Management, the National Oceanic and Atmospheric Administration, and the U.S. Coast Guard Navigation Center have worked together to repurpose some of the most important records and make these records available to the public. These records are sourced from the U.S. Coast Guard’s national network of AIS receivers called the Nationwide Automatic Identification System.

These data represent modeled, historical exposure of U.S. offshore and coastal waters to tropical cyclone activity within the North Atlantic Ocean basin. BOEM Outer Continental Shelf Lease Blocks and equivalent areas for coastal waters were used to construct the grid by which exposure was quantified. Exposure was quantified using intersecting storm tracks, overlapping wind intensity areas, and mathematical return intervals. Symbology is based on the modeled occurrence of 64-knot winds or greater per lease block. Wind climatology was based on Extended Best Track re-analysis data, using overwater wind data only. Due to the exclusion of inland wind values used within the model outputs, the interpretation of wind exposure metrics within coastal waters should be interpreted carefully. Storm tracks were provided by International Best Track Archive for Climate Stewardship (IBTrACS) data and limited to for the period 1900-2013. Data represent past climatology only and do not suggest predicted future impacts or exposure.

© MarineCadastre.gov This layer is a component of Tropical Cyclone Exposure (North Atlantic) - 64 Knots.

This map service represents modeled, historical exposure of U.S. offshore and coastal waters to tropical cyclone activity within the North Atlantic Ocean basin. BOEM Outer Continental Shelf Lease Blocks and equivalent areas for coastal waters were used to construct the grid by which exposure was quantified. Exposure was quantified using intersecting storm tracks, overlapping wind intensity areas, and mathematical return intervals. Symbology is based on the modeled occurrence of 64-knot winds or greater per lease block. Wind climatology was based on Extended Best Track re-analysis data, using overwater wind data only. Due to the exclusion of inland wind values used within the model outputs, the interpretation of wind exposure metrics within coastal waters should be interpreted carefully. Storm tracks were provided by International Best Track Archive for Climate Stewardship (IBTrACS) data for the period 1900-2013. Data represent past climatology only and do not suggest predicted future impacts or exposure. If you plan to ingest this service into your own application and would like to be informed about planned and unplanned service outages or changes to existing services, please register for our Data Services Newsletter (http://coast.noaa.gov/digitalcoast/publications/subscribe). For additional information, please contact the NOAA Office for Coastal Management (coastal.info@noaa.gov).

© MarineCadastre.gov

The oceanographic time series data collected by U.S. Geological Survey scientists and collaborators are served in an online database at http://stellwagen.er.usgs.gov/index.html. These data were collected as part of research experiments investigating circulation and sediment transport in the coastal ocean. The experiments (projects, research programs) are typically one month to several years long and have been carried out since 1975. New experiments will be conducted, and the data from them will be added to the collection. As of 2016, all but one of the experiments were conducted in waters abutting the U.S. coast; the exception was conducted in the Adriatic Sea. Measurements acquired vary by site and experiment; they usually include current velocity, wave statistics, water temperature, salinity, pressure, turbidity, and light transmission from one or more depths over a time period. The measurements are concentrated near the sea floor but may also include data from the water column. The user interface provides an interactive map, a tabular summary of the experiments, and a separate page for each experiment. Each experiment page has documentation and maps that provide details of what data were collected at each site. Links to related publications with additional information about the research are also provided. The data are stored in Network Common Data Format (netCDF) files using the Equatorial Pacific Information Collection (EPIC) conventions defined by the National Oceanic and Atmospheric Administration (NOAA) Pacific Marine Environmental Laboratory. NetCDF is a general, self-documenting, machine-independent, open source data format created and supported by the University Corporation for Atmospheric Research (UCAR). EPIC is an early set of standards designed to allow researchers from different organizations to share oceanographic data. The files may be downloaded or accessed online using the Open-source Project for a Network Data Access Protocol (OPeNDAP). The OPeNDAP framework allows users to access data from anywhere on the Internet using a variety of Web services including Thematic Realtime Environmental Distributed Data Services (THREDDS). A subset of the data compliant with the Climate and Forecast convention (CF, currently version 1.6) is also available.

U.S. Census Block GroupsThis feature layer, utilizing National Geospatial Data Asset (NGDA) data from the U.S. Census Bureau (USCB), displays Census block groups in the 50 states, the District of Columbia, and Puerto Rico. Per the USCB, "Block Groups (BGs) are clusters of blocks within the same census tract. Each census tract contains at least one BG, and BGs are uniquely numbered within census tracts. BGs have a valid code range of 0 through 9. BGs have the same first digit of their 4-digit census block number from the same decennial census. BGs coded 0 are intended to only include water area, no land area, and they are generally in territorial seas, coastal water, and Great Lakes water areas. Block groups generally contain between 600 and 3,000 people. A BG usually covers a contiguous area but never crosses county or census tract boundaries. They may, however, cross the boundaries of other geographic entities like county subdivisions, places, urban areas, voting districts, congressional districts, and American Indian / Alaska Native / Native Hawaiian areas".Block Group 2 - Census Tract 010400 (Santa Fe, NM area)Data version: This cached Esri federal service is checked weekly for updates from its enterprise federal source (Census Block Groups) and will support mapping, analysis, data exports and OGC API – Feature access.NGDAID: 70 (Series Information for Block Group State-based TIGER/Line Shapefiles, Current)OGC API Features Link: (U.S. Census Block Groups - OGC Features) copy this link to embed it in OGC Compliant viewersFor more information, please visit: What are census blocks?For feedback please contact: Esri_US_Federal_Data@esri.comNGDA Data SetThis data set is part of the NGDA Governmental Units, and Administrative and Statistical Boundaries Theme Community. Per the Federal Geospatial Data Committee (FGDC), this theme is defined as the "boundaries that delineate geographic areas for uses such as governance and the general provision of services (e.g., states, American Indian reservations, counties, cities, towns, etc.), administration and/or for a specific purpose (e.g., congressional districts, school districts, fire districts, Alaska Native Regional Corporations, etc.), and/or provision of statistical data (census tracts, census blocks, metropolitan and micropolitan statistical areas, etc.). Boundaries for these various types of geographic areas are either defined through a documented legal description or through criteria and guidelines. Other boundaries may include international limits, those of federal land ownership, the extent of administrative regions for various federal agencies, as well as the jurisdictional offshore limits of U.S. sovereignty. Boundaries associated solely with natural resources and/or cultural entities are excluded from this theme and are included in the appropriate subject themes."For other NGDA Content: Esri Federal Datasets

THIS MAP IS NOT AUTHORITATIVE. SEE TERMS OF USE BELOW.This web map was developed by the National Oceanic and Atmospheric Administration’s (NOAA) Office for Coastal Management and is featured in the U.S. Great Lakes Collaborative Benthic Habitat Mapping Common Operating Dashboard in support of the Collaborative Benthic Habitat Mapping in the Nearshore Waters of the Great Lakes Basin Project. This multi-year, multi-agency project is funded through the Great Lakes Restoration Initiative (GLRI) and focuses on new bathymetric data (airborne lidar and vessel based sonar) acquisition, validation, and benthic habitat characterization mapping of the nearshore waters (0-80 meters) in the U.S. Great Lakes. This project also contributes to the regional Lakebed 2030 campaign, which aims to have high-density bathymetric data available for the entirety of the Great Lakes by 2030. This web map contains data layers reflecting the current status of bathy data coverage in the nearshore (0-80 meters) of the U.S. Great Lakes, including acquisition (lidar and multibeam sonar), ground-truthing/validation, and benthic habitat mapping and characterization. Acquisition layers include coverage areas that have been acquired and are available for public use (green) as well as those that have been acquired, but are not yet available or are still in progress (orange). The nearshore water depth layers (0-25 and 25-80 meters) were created using the National Centers for Environmental Information (NCEI) Great Lakes Bathymetry (3-second resolution) grid extracts. The 0 to 25 meter nearshore water depth layer represents areas where bathymetric lidar data acquisition could ideally be conducted, depending on water condition and turbidity. The 25 to 80 meter layer shows locations where acoustic data acquisition can occur. The acquired data values are all in sq. km and were created by merging and dissolving all publicly available bathy lidar and multibeam sonar coverage polygons into single layer and erasing from the nearshore water depth layers (0-25, 25-80, and 0-80 meters). All polygon layers were clipped using the USGS Great Lakes subbasin polygon shapefile and the U.S./Canada boundary from the International Boundary Commission (version 1.3 from 2018). All data originally projected in the following coordinate system: EPSG:3175, NAD 1983 Great Lakes and St Lawrence Albers.This map will continue to be updated as new information is made available.See below for information on additional data layers. Source Data for Bathy Coverage Layers - Acquired/Available:Topobathy and Bathy Lidar (NOAA's Data Access Viewer: https://coast.noaa.gov/dataviewer/#/; U.S. Interagency Elevation Inventory (USIEI): https://coast.noaa.gov/inventory/). Multibeam Sonar (National Centers for Environmental Information (NCEI) Bathymetric Data Viewer: https://www.ncei.noaa.gov/maps/bathymetry/; NOAA's Data Access Viewer: https://coast.noaa.gov/dataviewer/#/; U.S. Interagency Elevation Inventory (USIEI): https://coast.noaa.gov/inventory/; USGS ScienceBaseCatalog: https://www.sciencebase.gov/catalog/item/656e229bd34e7ca10833f950)Source Data for Bathy Coverage Layers - GLRI AOIs (2020-2024):Acquisition: NOAA Office for Coastal ManagementValidation/CMECS Characterizations: NOAA National Centers for Coastal Ocean Science (NCCOS)Source Data for Bathy Coverage Layers - In Progress and Planned:NOAA Office of Coast Survey Plans: https://gis.charttools.noaa.gov/arcgis/rest/services/Hydrographic_Services/Planned_Survey_Areas/MapServer/0NOAA Office for Coastal ManagementSource Data for Nearshore Water Depths:NOAA's National Centers for Environmental Information (NCEI) Great Lakes Bathymetry (3-second resolution) grid extracts: https://www.ncei.noaa.gov/maps/grid-extract/Source Data for Spatial Prioritization Layers:Great Lakes Spatial Priorities Study Results Jun 2021. https://gis.charttools.noaa.gov/arcgis/rest/services/IOCM/GreatLakes_SPS_Results_Jun_2021/MapServerMapping priorities within the proposed Wisconsin Lake Michigan National Marine Sanctuary (2018). https://gis.ngdc.noaa.gov/arcgis/rest/services/nccos/BiogeographicAssessments_WILMPrioritizationResults/MapServerThunder Bay National Marine Sanctuary Spatial Prioritization Results (2020). https://gis.ngdc.noaa.gov/arcgis/rest/services/nccos/BiogeographicAssessments_TBNMSPrioritizationResults/MapServerSource Data for Supplemental Data Layers:International Boundary Commission U.S./Canada Boundary (version 1.3 from 2018): https://www.internationalboundarycommission.org/en/maps-coordinates/coordinates.phpNational Oceanic and Atmospheric Administration (NOAA) HydroHealth 2018 Survey: https://wrecks.nauticalcharts.noaa.gov/arcgis/rest/services/Hydrographic_Services/HydroHealth_2018/ImageServerNational Oceanic and Atmospheric Administration (NOAA) Marine Protected Areas (MPA) Inventory 2023-2024: https://www.fisheries.noaa.gov/inport/item/69506National Oceanic and Atmospheric Administration (NOAA) National Marine Sanctuary Program Boundaries (2021): https://services2.arcgis.com/C8EMgrsFcRFL6LrL/arcgis/rest/services/ONMS_2021_Boundaries/FeatureServerNational Oceanic and Atmospheric Administration (NOAA) U.S. Bathymetry Gap Analysis: https://noaa.maps.arcgis.com/home/item.html?id=4d7d925fc96d47d9ace970dd5040df0aU.S. Environment Protection Agency (EPA) Areas of Concern: https://services.arcgis.com/cJ9YHowT8TU7DUyn/arcgis/rest/services/epa_areas_of_concern_glahf_viewlayer/FeatureServerU.S. Geological Survey (USGS) Great Lakes Subbasins: https://www.sciencebase.gov/catalog/item/530f8a0ee4b0e7e46bd300dd Latest update: February 20, 2025

This Office of Coast Survey map layer depicts the following U.S. maritime boundaries: Territorial Sea (12 mile), Nautical Contiguous Zone (24 miles) and the Exclusive Economic Zone (200 miles). Territorial sea: The maritime zone over which the United States exercises sovereignty. Sovereignty extends to the airspace above and to the seabed below the territorial sea. The U.S. territorial sea extends 12 nautical miles from the baseline.Contiguous zone: The contiguous zone of the United States is a zone contiguous to the territorial sea. In this zone, the U.S. may exercise the control necessary to prevent and punish infringement of its customs, fiscal, immigration, cultural heritage, or sanitary laws and regulations within its territory or territorial sea. The U.S. contiguous zone is measured 24 nautical miles from the baseline. Exclusive Economic Zone: The exclusive economic zone (EEZ) of the U.S. extends 200 nautical miles from the territorial sea baseline and is adjacent to the 12 nautical miles territorial sea of the U.S., overlapping the 12-24 nautical miles contiguous zone. Within the EEZ, the U.S. has:sovereign rights for the purpose of exploring, exploiting, conserving and managing natural resources, whether living and nonliving, of the seabed and subsoil and the superjacent waters and with regard to other activities for the economic exploitation and exploration of the zone, such as the production of energy from the water, currents and windsjurisdiction as provided for in international and domestic laws with regard to the establishment and use of artificial islands, installations, and structures, marine scientific research, and the protection and preservation of the marine environmentother rights and duties provided for under international and domestic lawsMaritime Limits BoundariesData currency: current federal service (MaritimeBoundaries/US Maritime Limits Boundaries)For more information: U.S. Maritime Limits & BoundariesFor feedback please contact: ArcGIScomNationalMaps@esri.comThumbnail image courtesy of Elijah G. Leinaar

The Digital Elevation Model (DEM) utilized for this Willamette FIS submittal was produced by combining multiple overlapping topographic surveys for the Middle Fork and Coast Fork of the Willamette River. The DEM was created from four sources: LIDAR of the Springfield area that was flown in 2008, LIDAR of Silk Creek that was flown in 2011, LIDAR of Fall Creek that was flown in 2012, and photogrammetry of the Middle Fork and Coast Fork of the Willamette River that was flown in 2004. In areas where no high-resolution elevation data were available, USGS National Elevation Dataset (NED) data were used to supplement the DEM. This feature represents the areas NED information is presented. The horizontal datum of the DEM is NAD 1983 State Plane-Oregon South HARN with units of International Feet (NAD83). The vertical datum of the elevation model is NAVD 1988 with units of international feet (NAVD-88). The lower resolution elevation data means that there is less confidence in the flooded area polygon and water depth for a particular water surface elevation.

This layer is the US/Canada international boundary, which extends on land and through the Great Lakes.

The United States Bathymetry Gap Analysis is a map service providing visual access to the local sounding density derived from all modern bathymetric data holdings at NOAA's National Centers for Environmental Information (NCEI) and Office for Coastal Management (OCM). A team from NOAA's Office of Coast Survey, the University of New Hampshire Center for Coastal and Ocean Mapping/Joint Hydrographic Center, and NCEI - Colorado prepared this analysis and map service to inform a U.S. ocean and coastal mapping strategy for U.S. waters and contribute to the international Seabed 2030 initiative, which aims to map the entire ocean floor at 100 meter resolution by 2030.

Underpinning the map service are seven principal layers of bathymetry. Actual soundings of multibeam data (raw), single beam data (1960 or later), NOS hydrographic surveys (1960 or later), and crowdsourced bathymetry are included. Coverage footprints of NOS BAG-formatted hydrography, bathymetric grids from the U.S. extended continental shelf survey program, and bathymetric LIDAR data are also included. All bathymetry layers used in the gap analysis are archived at NCEI. For convenience, footprints of bathymetric LIDAR data were retrieved from NOAA's Digital Coast.

To effectively manage server resources, the analysis is partitioned across 178 tiles covering all U.S. waters and adjacent continental shelf. Each tile spans 6 degrees in longitude and 4 degrees in latitude. Within this framework, all modern depth soundings or coverage footprints are extracted from NCEI and OCM data holdings and associated with an approximately 100-m resolution grid of the area. MB_System, GDAL, GMT, and Esri ArcGIS software are used to prepare this analysis. While data quality is not the focus of this analysis, the following 12 multibeam surveys that were identified by GMRT as containing poor or bad quality data have been excluded: AT19, EW0101, EW0205, EW0206, EW0210, EW0310, EW0401, EW0501, EW9002, EW9501, KN145L18, and KN190. This change took effect in the August 2020 update, in order to provide more clarity about the current status of mapping coverage over these surveyed areas.

To simplify the visual presentation and accommodate evolving views on the number of soundings needed for a single 100 m cell to be "mapped", the number of soundings for each grid tile are divided into categories of coverage. Sounding densities greater than 0 and less than 3 are reclassed to a value of 1 and displayed as a deep pink color. This value represents "minimally mapped" in this analysis. Sounding densities equal to 3 or greater are reclassed to a value of 3 and displayed as a deep purple color. The coverage footprints obtained from the BAG-formatted hydrography, offshore extended continental shelf grids, and nearshore bathymetric LIDAR were populated with a value of 3, which represents "better mapped" in this bathymetry coverage and gap analysis.

Legend:

This layer contains the US 200nm EEZ as well as adjacent international maritime boundaries, where the US EEZ would otherwise overlap another coastal State.