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Fate of 'Magenta Line' Will Be In Our Hands, NOAA Says


NOAA’s Office of Coast Survey is wondering whether the time has come to get rid of the magenta line on Intracoastal Waterway Charts, and an informal poll of ICW boaters and others failed to clarify the matter.

Coast Survey noted that the magenta line—some call it the “magenta highway”—has been on ICW charts for 77 years, during which time GPS and electronic navigational charts were introduced and are in widespread use.

In July, the public was asked two questions:

1. Is there still a need for the magenta line?

2. What do today’s users of the ICWW want the magenta line to be? An indication of the channels the ICWW follows or a suggested route for traveling the ICWW?

According to Dawn Forsythe from the Office of Coast Survey, 62 people answered some or all the questions. Of those, all but seven percent were familiar with the Intracoastal Waterway and 73 percent were very familiar with it. The biggest group of responders, 40 percent were recreational boaters, 30 percent operated commercial craft, 10 percent were coastal merchants and 21 percent listed themselves as “other.”

These people had different understandings of what the magenta line signifies.

Thirty-six percent believed it to be “a recommended route showing the best water down the ICWW;” 46 percent thought it was s a “line down the middle of the ICWW channel and 18 percent said it was a “guide showing the channels that the ICWW uses.”

Boating writer and ICW expert Tom Neale once wrote:

“Years ago when the ICW was younger and dredging more frequent, ICW chart makers generally drew a magenta line to follow the channel. Popular legend was that if you stayed on the Magenta Line you’d have plenty of water. Kind of like that yellow brick road. But the channels of the ICW have been changing every day. So sometimes the magenta line works and sometimes it doesn’t. That’s why we pay careful attention to the fixed and floating aids to navigation. They’re more likely to be in the right place. Sometimes.”

More than a third of the respondents—37 percent—want the magenta line to be a recommended route showing deepest water. Meanwhile 26 percent want it show the channels and 27 percent it to represent a trackline down the middle of the ICW channel

Clearly, of those who were asked and who responded to the questions, there is no overwhelming majority favoring one option or another. So Coast Survey will develop options and solicit public opinion through the Federal Register “request for comments” process,” Forsythe said. This comment process if more formal, and it will likely elicit a greater number of responders. Stay tuned for more information about the future of the magenta highway.