1. Digital Maritime Zones and National Baseline on NOAA’s Nautical Charts
Meredith Westington
NOAA’s Office of Coast Survey
Exclusive Economic Zone
Three Nautical Mile Line
Territorial Sea
Snapshot of chart 18740, 40th edition
Contiguous Zone
(shown at 12nm prior to 1999)

2. Territorial Sea Area of sovereignty Innocent passage
Outer extent moved from 3 to 12 nautical miles through Presidential Proclamation in 1988
Territorial Sea
Snapshot of chart 18740, 40th edition

3. Contiguous Zone Zone is contiguous to the territorial sea
Coastal state can exercise control necessary to protect infringement of the following regulations:
Customs
Fiscal
Immigration
Sanitary
Outer extent moved from 12 to 24 nautical miles through Presidential Proclamation in 1999
Contiguous Zone
(shown at 12nm prior to 1999)
Snapshot of chart 18740, 40th edition

4. Exclusive Economic Zone
Zone is contiguous to the territorial sea
Outer limit cannot exceed 200 nautical miles from the baseline from which the territorial sea is measured
Sovereign rights and jurisdiction over EEZ resources and activities
Respect rights of navigation and over flight consistent with international law
EEZ declared through Presidential Proclamation in 1983
EEZ
(maritime boundary with Mexico)
Snapshot of chart 18740, 40th edition

5. Three Nautical Mile Line
Outer limit of the territorial sea prior to 1988 Presidential Proclamation
Ambulatory line projected 3 nautical miles from the baseline from which the territorial sea is measured
Not necessarily the same as the Submerged Lands Act federal/state boundary
Used for federal fisheries, water quality, and other laws or regulations
May be used by U.S. states to regulate laws
Three Nautical Mile Line
Snapshot of chart 18740, 40th edition

6. Law of the Sea Guidelines for delimiting the maritime zones
Articles set forth criteria for determining the “baseline”

7. Normal Baseline
Contributing Baseline Points
Low-water line along the coast as marked on large-scale, officially recognized charts.

8. U.S. Baseline Committee Created: August 7, 1970
Purpose: To provide an interagency forum to discuss and make determinations on all questions relating to the official delimitation of the U.S. Coastline
Chaired by the Department of State with representatives from
Department of Commerce (NOAA)
Department of Justice
Department of Interior (MMS, FWS)
Department of Homeland Security (USCG)
Department of Navy
Department of Defense (NGA)
Environmental Protection Agency (EPA)
Federal Communications Commission

9. Evaluating the Baseline
Low-tide elevations- naturally formed features must be dry at low tide (Article 13)
Permanent harborworks- features must form an integral part of the harbor system (no artificial islands- Article 11)
Bay closing lines- well-marked indentations of the land that meet several tests can be closed with a straight line (normal baseline only- Article 10)

10. 3nm Line drawn from baseline with jetty
Baseline vs Coastline
3nm Line
without jetty
3nm Line drawn from baseline with jetty

11. Caris’ Law of the Sea: Limits & Boundaries Envelope of Arcs
To retrieve the contributing baseline points and limit line (ex. Gardner Pinnacles, NWHI)
Vector LWL
Contributing Baseline Points
THREE NAUTICAL
MILE LIMIT

12. Updates to Paper/Raster Nautical Charts
THEN- Territorial Sea and Contiguous Zone are both projected 12 nautical miles from baseline
NOW- Territorial Sea at 12 nautical miles and Contiguous Zone at 24 nautical miles from baseline

13. Availability on the Web
EEZ is Available Now!
Available in shp and dbf formats
Credit: FWC
Created from CARIS software and provided in shapefile format
NEW Maritime Limits Website!

14. NOAA Electronic Navigational Charts
ENC equivalent to chart (Louisiana)
The area covered by an NOAA ENC is referred to as a "cell." At present, each NOAA ENC cell corresponds to the largest scale paper chart in a given area. As the NOAA ENC begins to contain more detail and the file sizes get larger, it may become necessary to split the cells into smaller areas
ENC equivalent to chart 11353
Created in dKart’s dkLook (free chart viewer)

15. Two Methods of downloading ENCs for Navigation
ENCs: Free Internet Download
Two Methods of downloading ENCs for Navigation

16. Territorial Sea in ENCs: Depiction of Zone at West Coast of Florida

17. Territorial Sea in ENCs:
Depiction of Inner Limit at West Coast of Florida
ENC Symbology for COLREGS demarcation line – magenta dashed line
ENC Symbology for “Territorial Sea Area” – black dashed line

18. Exclusive Economic Zone
Summary
ENC downloads
Exclusive Economic Zone
Maritime Limits