Digital charts have been available for more than a decade, but they were never cheap. So when the government announced two years ago that it was giving away its entire catalog of electronic charts for free, it became one of the hottest topics on the coconut telegraph.

So, what is the story behind the free charts? The answer is that the federal agency charged with supplying marine cartography is stepping quickly into the digital age, and its actions are reshaping the marketplace.

When the National Oceanic and Atmospheric Administration introduced Raster Navigational Charts in 1995, it did so as part of a Cooperative Research and Development Agreement with Maptech Inc. The charts were simply digital images of traditional paper charts, but the partnership made Maptech the only official source of NOAA's electronic charts.

Maptech distributed files in a format known as "BSB," which remains a trademark of Maptech. Other companies circumvented Maptech's exclusive agreement by scanning paper charts themselves and creating files in other formats. For example, SoftChart sold CD-ROMs of charts in the GEO/NOS format, which was supported by many charting software manufacturers.

Under the arrangement between NOAA and Maptech, electronic charts were available, but they were relatively expensive and many recreational boaters chose to use the same charts year after year rather than pay for an update. NOAA and the U.S. Power Squadron estimated that many vessels carried charts that were an average of four years out of date, which some critics said was a safety issue.

TURNING POINT

That all changed in August of 2005, when NOAA's agreement with Maptech expired. According to Tom Loeper of NOAA's Marine Chart Division, the agency initiated a new two-step strategy to get electronic charts into the hands of more boaters.

First, NOAA announced that its entire raster chart library, covering all U.S. waters with about 1,000 charts, would be available as free downloads. And free they are. Anyone with an Internet connection can download raster charts on the NOAA site and, employing PC-based navigation software, put them to use.

NOAA also established a process whereby distributors are authorized to package electronic chart files and make them available conveniently and affordably. These Certified Raster Navigational Chart Distributors sell chart sets packaged on CD-ROM or DVD-ROM to boaters who do not want to download their own.

You don't need an advanced degree in economics to realize that when NOAA released its charts for free, prices for electronic cartography plummeted. Now you can pick up large regions of electronic charts for under $10–for that matter, for free–simply by browsing the web.

This lowered the price of admission for boaters who have never used electronic charting. By combining your laptop or desktop computer with a free or trial software package, you can inexpensively see if electronic charting and navigation is for you. If you already use a laptop-based electronic charting system, this means you can update your charts more frequently at lower cost.

INTERNATIONAL CHARTS

There are some limitations. The revolution that led to free charts only covers United States waters, including those surrounding U.S. territories such as Puerto Rico, the U.S. Virgin Islands and assorted smaller Caribbean and Pacific Islands. Coverage also exists for Hawaii, Alaska, and the Great Lakes.

Popular cruising areas outside of the U.S.–including the Bahamas, Mexico, Canadian ports on the Great Lakes or the Inside Passage to Alaska through British Columbia–are not covered.

The acquisition of SoftChart by Maptech in 2006, combined with the increasing popularity of NOAA free charts, has made the BSB format the de facto national standard for U.S. raster charts. But for cruising outside the U.S., electronic charts must be purchased through private vendors and other standards are often used.

In Britain, a standard known as ARCS is in place and in Australia it is called Seafarer. If you plan to cruise internationally and use raster charts, be sure your charting software supports other national standards. Vector charts, which are based on a database rather than an image of a paper chart, abide by an international standard called "S-57," so the charts generally work across different charting systems.