Do you need a new chart?

New update information service makes decisions easier

NOAA privatized printing of paper nautical charts in 2014 and, in the ensuing years, focused on modernizing chart compilation and production. Those recent changes allow us to update both paper and digital charts on a weekly basis. However, mariners still have had to deal with a cumbersome Local Notice to Mariners process to get important (or less than important) updates to the charts that they already own. Coast Survey is now making life a little easier for chart users.
Prior to 2014, when the government printed paper charts, it was easy to decide when to purchase a chart: when NOAA issued a “new edition.” Until that new edition came out, users just penciled in the updates as provided in the Local Notice to Mariners. Now, however, we are updating the actual charts before issuing new editions, on a weekly basis. Obtaining the latest updated chart, either by downloading a digital/electronic version or by purchasing a new paper chart from NOAA-certified vendors, is much easier. But is it necessary? Do the chart updates justify a cash outlay for the latest version?

How do you know when it is time to get a new chart?

Coast Survey is making a fundamental change in how we inform users about chart updates. The idea is to give users the ability to visually identify where all changes are occurring on their charts each week. With that information, you can make your own determination about when you may want to purchase an updated paper chart or download an updated raster or electronic navigational chart.
The new weekly chart updates webpage provides users with weekly information about specific changes in water depths, shoreline, obstructions, or other features on NOAA’s nautical charts.

One glance will tell you if the chart in your area has been updated. Click on the red dot for more info, and scroll back through the weeks to see prior changes.
One glance will tell you if the chart in your area has been updated. Click on the red dot for more info, and scroll back through the weeks to see prior changes.

Progressing past the legacy

This improvement reflects a basic shift in how we update the charts and how the public learns about those changes.
Since the mid-1850s, Coast Survey would collect updates for each chart, for one, five, or ten years, and would then create a new edition of that chart. Hundreds or thousands of copies would be printed and shipped out to sit on the shelves in boat shops and marine centers – until the next edition came out in one or five or ten years.
Now, Coast Survey constantly applies updates to the charts, and those updated charts are issued and available for sale on a weekly basis.  They are not “new editions,” however. Constantly issuing “new editions” would force commercial mariners to constantly purchase the editions (since many mariners are required to carry the latest edition on their voyages). We needed to hit the happy medium.
Although we are moving past the legacy of “new editions,” Coast Survey has developed an algorithm that periodically will identify a chart that meets the basic criteria for issuance as a new edition, which we post at weekly chart updates along with our normal notification in the DOLE.  This service allow users to see both LNM-based chart updates (for critical information) and non-LNM-based chart updates (which are non-critical).

Basic instructions

When the interface comes up, enter a chart number or an ENC cell number. As you begin to type a number in the box, you will be able to access a drop down of applicable charts or ENCs. 
The program allows the user to view data in one-week increments, and you may begin at any week. You can cycle through, week by week, by clicking the up or down arrows next to the date in the “week ending” box.
The right side of the screen shows the list of charts with corrections for the selected week. The first number is the number of LNM (critical) corrections, and the second number represents chart updates that were made but do not appear in the LNM. Red dots represent critical items while brown polygons show the limits of non-critical updates.
Clicking on any chart in this list will open that chart. Clicking on those dots or polygons will provide information about the correction itself.   
Currently, an item may fall in both the critical and non-critical categories if the LNM was originated on the NOAA side (i.e., if NOAA evaluated and compiled a piece of information and then provided the information to the U.S. Coast Guard for publication in the LNM).
You can create a csv file for corrections on any week. Use the download icon next to the question mark icon (info).  When you click on the downloaded file it will default to open in Microsoft Excel.

2 Replies to “Do you need a new chart?”

  1. I find this version rather laborious. You have to go week by week, then select the chart, then review the changes.
    If instead, you use the earlier chart updates link: https://ocsdata.ncd.noaa.gov/ntm/Default.aspx
    you can get a summary of changes (by chart). You select the chart, then the edition, then all the changes pop up for that “edition”.
    Pam C-K, former NOAA-C&GS surveyor

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