NOAA 50th Anniversary
Office of Coast Survey
National Oceanic and Atmospheric Administration
U.S. Department of Commerce

NOAA Custom Charts

What is the NOAA Custom Chart web application?

NOAA Custom Chart (NCC) is an online application that enables users to create their own customized nautical charts directly from the latest official NOAA electronic navigational chart (NOAA ENC®) data.

NCC outputs geospatially referenced Portable Document Format (PDF) files using the paper size, scale, and location selected by the user. Depths can be displayed in meters, feet, or fathoms and there are a few other display options, such as changing the depth at which a shallow water blue tint is applied and the depiction of a "safety contour" based on a vessel's draft.

The data portrayed on NCC charts is referenced to the World Geodetic System 1984 (WGS84) datum and reference system, and charts are created in the Mercator projection. The best output is produced when a chart scale matching the scale of the available ENC data, and an appropriate paper size are selected for the custom chart. NCC charts are composed in a standard rectangular format featuring a single chart panel (i.e., there are no insets). The data inside the chart panel is presented in a manner similar to traditional paper nautical charts, showing soundings, buoys, beacons and other aids to navigation, compass roses and the like, although some chart symbology may differ slightly. A graphic and a representative fraction scale, and other marginalia appear below the chart panel. Separate 8.5" x 11" PDF pages contain notes and a zone of confidence or CATZOC diagram, similar to the survey source diagrams seen on traditional nautical charts.

NOAA custom charts do not have numbers and U.S. Coast Guard (USCG) Local Notice to Mariners (LNM) will not be issued for NCC charts. The USCG will continue to provide information about changes to aids to navigation in the Discrepancies, Temporary Changes, and Light List Corrections sections of the LNM. Any references to NOAA traditional chart numbers will eventually be replaced with standard “harmonized” waterway and other place names to provide the general location of changed features in addition to the precise longitude and latitude of the changes.

Coast Survey’s Weekly Chart Updates website can also be used to identify the location of corrections applied to the ENCs that are used to create NCC charts (and traditional paper charts that have not yet been canceled). These include critical corrections published in an LNM, as well as routine non-critical corrections that are regularly released by NOAA. These corrections are displayed against a map and can be queried by the user to obtain more information.

Charts output from NCC do not meet carriage requirements for USCG regulated vessels. There is a chance the NCC output could meet carriage requirements sometime in the future, but this is not a certainty. Additional enhancements to the NCC application are required and other conditions would have to be met related to the ENC data used, the scale of the chart being created, and the manner in which the chart is printed.

NOAA is working with its certified Print on Demand (POD) chart agents to provide an easy way for customers to obtain large-format copies of their custom charts.

NOAA Custom Chart of Nantucket Island, Massachusetts

Frequently Asked Questions

  • The portrayal of data on NCC charts now more closely follows the color palette used on traditional NOAA nautical charts and NOAA symbology for navigational aids (buoys, beacons, and navigational lights) and other critical features is now available.
  • A Zone of Confidence (ZOC) diagram, similar to a source diagram on traditional paper charts, now shows the relative accuracy of the hydrographic surveys used to compile depths depicted on the NCC chart.
  • The chart notes output is more complete, with local, regional, and global notes exported for the exact extent of the chart.
  • More paper sizes, including legal (8.5” x 14”), ledger/tabloid (11” x 17”), and other large format sizes are being added. User defined paper sizes are not possible, because a standard template defining the placement of various elements of chart marginalia must be created for each paper size output.
  • Currently, compass roses sometimes appear at the edge of a chart or are not spaced appropriately for the scale of the chart being created.
    We hope to resolve this issue soon. In the meantime, users can toggle the display of compass roses off in the NCC Display Settings and use a protractor aligned to the chart latitude/longitude grid to plot bearings. If compass roses are toggled off, a small magenta arrow is displayed with the magnetic variation from true north. Variation to the east is indicated with a positive number (as shown below), variations to the west are indicated with a negative number. Users should be careful not to confuse this number with a sounding, which looks similar, especially if the variation is a whole number, as is the case in the example below.
  • NCC charts still depict some features with symbols that are more familiar to those using the Electronic Chart Display and Information System (ECDIS) navigational equipment typically used by large commercial vessels.
    We are gradually replacing these representations with the colors and symbols currently used on traditional NOAA paper chart symbology. Ultimately, NCC will provide an option to create charts with either of these symbology sets.
  • The swing circles for anchor berths are not currently depicted. We are working to fix this as we improve other symbolization on NCC charts.
  • Text associated with some features, such as Code of Federal Register (CFR) references for anchorages and restricted areas is not currently displayed on NCC charts.
    Improved display of labels and other text within the chart, including text related to aids to navigation will be provided in an upcoming enhancement of NCC.
  • We are looking into improving the logical order of the chart notes provided on separate 8.5" x 11" pages in the NCC output. Improvements to the geospatial database that is the source of the note text are also being made to ensure that only the appropriate notes for the charted area are displayed.
  • The mathematical rounding used by NCC when converting depth units in meters to feet or meters to fathoms will usually result in displaying a sounding or other depth value that is one unit shallower than the same depth shown on the corresponding traditional paper nautical chart. Rounding of depths on nautical charts is not as straightforward as the rules that are taught in elementary school. Special considerations are taken to always round "on the side of safety" which complicates the conversion of depth units that is provided by NCC.
    We are working on ways to resolve this so that the same maximum safe depths can be shown on all NOAA chart products.
  • The magenta “Data extent” boxes that are displayed in the NCC map window and are controlled within the Miscellaneous tab of the NCC Display Settings control panel show the minimum bounding rectangle (MBR) of the individual ENC cells that are used to create NCC custom charts. If an ENC cell is rectangular and is aligned with lines of longitude and latitude, then the extent of the ENC and its MBR will match. However, if the ENC is irregularly shaped, skewed, or composed of noncontiguous parts, then the MBR for the ENC will enclose areas which are not covered by the ENC data at the scale indicated, as shown in the examples below.
    We are exploring different ways to make it easier for users to determine the exact extent and scale of the underlying ENC data that NCC uses to build custom charts
  • Depth contour labels are sometimes spaced too closely or too far apart. We are working on ways to improve the scale appropriate placement of contour labels.
  • Occasionally, the latitude and longitude labels associated with the chart grid may overlap each other. We hope to resolve this problem soon.

Unlike popular online maps or car navigation systems, which often provide a “seamless” map display as users zoom in, nautical charts only have large scale data in particular areas - usually ports. You can only build a custom chart with the ENC data that is available and at the scale at which it was compiled.

For example, if you wanted to build a 1:20,000 scale chart for a trip from Buhne Point in Humboldt Bay, California to the Pedrazzini Boat Ramp on the Eel River, you might set a chart extent, as shown by the red filled box below, for a 34” x 44” (ANSI E) sheet. A red outline covering Arcata Bay to the northeast to Humboldt Bay to the southwest shows the extent of a 1:25,000 scale ENC cell. This is a bit smaller scale then the 1:20,000 scale that the NCC chart will be created at, but the difference is fairly small and this portion (the northeast quadrant) of the resulting chart should look fine.

However, the largest scale ENC coverage available in the NW, SW, and SE quadrants is only 1:200,000. This is ten times smaller than the 1:20,000 scale chart that the NOAA Custom Chart tool is being used to create. That is, the ENC data available for the rest of the chart (shown by the larger red outline in the image below) was generalized when the smaller scale ENC cell was compiled and it shows ten times less detail.

This difference is readily apparent in the resulting chart, shown below. The density of the soundings in the northeast quadrant of the chart is much greater, there are more depth contours shown, and the delineation of the sloughs in Humboldt Bay is more detailed than the banks of the Eel River shown in the southern portion of the chart.

NCC charts do not currently meet USCG carriage requirements for paper charts. NOAA is working with the USCG and making modifications to the NCC chart output, which may result in NCC charts meeting carriage requirements in the future, but if and when this might occur is not certain. In any event, not all custom chart output would meet carriage requirements, even after the enhancements to the NCC application are made, as other conditions would also have to be met related to the ENC data used, the scale of the chart being created, and the manner in which the chart is printed.

NCC uses the latest up-to-date NOAA Electronic Navigational Chart (NOAA ENC®) data to create customized charts. Although NCC charts do not currently meet U.S. Coast Guard paper chart carriage requirements for regulated vessels, they should be adequate for use by recreational boaters, especially as a backup for other navigation systems. All recreational and professional mariners are encouraged to use ENCs for their primary means of navigation.

There is a growing demand for ever more detailed nautical charts. To help meet this need, NOAA initiated a program to sunset its traditional paper nautical charts and the corresponding raster chart products and services. This has enabled NOAA to focus on improving the coverage and content of the digital chart format that is used throughout the world for navigation, the electronic navigational chart (ENC). ENC data is produced by over twenty other countries and used by mariners around the world.

Producing and distributing raster charts requires additional, separate computer software and data storage, as well as specialized cartographic training and processing beyond the resources needed to maintain ENCs. NOAA now maintains over 1700 ENCs and is carrying out an ambitious program to replace much of the existing ENC coverage with more detailed (larger scale) data. When completed, the enhanced ENC product suite will consist of over 9000 ENCs in eleven standard scales. NOAA has only been able to create and maintain this enhanced suite of ENC products by redirecting resources previously used to update and distribute traditional paper and raster nautical charts.

NCC creates PDF document files that can be downloaded and printed at home. For larger size charts, NOAA is working with our certified Print on Demand (POD) chart agent partners to create a business model for printing and distributing large format plots of NOAA Custom Charts. Some POD agents may also be developing their own chart products from NCC output that customers will be able to order online in a manner similar to how traditional NOAA POD paper charts are sold today.

The geospatial Portable Document Format (PDF) is the only output provided by the NOAA Custom Chart. The PDF is geospatially referenced, but NCC charts are not intended to be used in digital chart displays for navigation.

No, only specific paper sizes shown in the NCC Print Settings control panel may be used. The placement of the chart grid, graphic scales, notes and other marginalia must be designed for each paper size and orientation used by NCC.

Yes. A new 14 page User Guide was released with NCC version 1.0. This explains how the various application settings work and provides tips for creating the best customized charts. There is also a five-minute video that discusses setting chart limits and outputting custom charts.

For further assistance or to suggest improvements for NOAA Custom Chart application, questions or comments may be submitted through the Coast Survey’s online ASSIST customer feedback tool.

If you have a question or suggestion concerning a particular NCC chart that you are trying to create, please let us know what area you are trying to build a chart for and attach the NCC chart PDF or a screenshot of the area, if possible.

Once a traditional nautical chart has been cancelled, it (and many other previous editions of the chart) will be available in a jpeg format in the NOAA Coast Survey Historical Map and Chart Collection. Canceled charts do not meet USCG carriage requirements for regulated vessels and should not be used for navigation.

Revised: 3/9/2020