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End of the line? - Soundings Online

End of the line?

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When NOAA announced last month that it is considering eliminating the “magenta line” from government charts of the ICW, I had to laugh. During the summer, a little jaunt from Florida to Charleston, S.C., and back had made NOAA’s point for me.

In a notice soliciting advice from the boating public, NOAA’s Coast Survey people expressed what for many ICW denizens was obvious:

Numerous examples can be found where the charted Intracoastal Waterway Route (“magenta line”) passes on the wrong side of aids to navigation; crosses shoals, obstructions, shoreline; and falls outside of dredged channels, etc.

And, in fact, the Coast Survey has already removed the line, which I have always preferred to call the “magenta highway,” from some of the charts where the problems were most egregious. When I call it a highway, I am only half joking. Some novice boaters ride it like the center lane on the interstate, and who can blame them? This is what was intended when it was first drawn in the 1930s.

“It was added to the charts to show the best route,” says Dawn Forsythe, of the Office of Coast Survey. “It has not been maintained over the decades, however, so it no longer depicts the best route. For safety reasons, we are currently removing it as charts are updated. We are considering what the magenta line should be going forward or, indeed, whether it should continue to exist at all.”

The “best route” on this NOAA chart for the Crooked River in Georgia suggests you cut two red marks and cross a mudbar.

The “best route” on this NOAA chart for the Crooked River in Georgia suggests you cut two red marks and cross a mudbar.

Anyway, let me recount a little experiment I conducted aboard Rio, my 41-foot sailboat, while running “The Ditch” south through Georgia, where you will go aground if you assume the magenta highway is the best route. We were approaching a devilishly confusing bend in the Crooked River. Southbound the reds are supposed to be to starboard here, but on our government chart it looks as if obeying the marks will put you on the shoal just past the red “60.”

ROUTE A OR B?

All of the electronic cartography and PC navigational software reproduce the magenta line on their products. I happened to be looking at Navionics that day. Lo and behold, Navionics portrayed not one, but two magenta lines. What’s a simple mind to think? My boat draws just over 4 feet and her long, full keel is a forgiving thing. “Let’s give them both a try,” I told my crew, and we ran right down Magenta A and Magenta B.

Navionics outdoes NOAA by suggesting two paths that cut the marks and cross the bar.

Navionics outdoes NOAA by suggesting two paths that cut the marks and cross the bar.

So what happened? Softly touched mud following A, reversed to deep water and ran back a couple hundred feet upriver to pick up B. We followed B, and guess what? We went aground again, doing a more thorough job this time. I ordered everyone on board to go stand as far forward on the bow as they could. When the cocker spaniel and the maltese saw everyone (except me) hurrying forward, they ran, too. The weight of two men, a woman, a boy and 45 pounds of collective canine tipped the skeg out of the muck and we again reversed off.

Now what? It’s 2013. What else would anyone do? I picked up my smartphone and consulted the crowd-sourced ActiveCaptain online cruising guide available on my Plan2Nav charting app from C-Map. Some cruisers who had passed through here recently had revealed a cure for Crooked River fever. I then opened up Navionics’ charting app on the phone. In the community layer — crowd-sourced navigationally significant info — there was confirmation from other mariners who also had made the same transit recently.

Obey the marks, both sources said (why didn’t I think of that?). Forget about that shoal depicted to port. Trust us, they said, it’s not there. So we steered over the area indicated as shallow and we found 12 feet of water all the way around the bend.

However, using the ActiveCaptain online cruising guide and Navionics’ own crowd-sourced chart overlay, a third route is revealed. Note that it crosses another mudbar, except that this one does not exist.

However, using the ActiveCaptain online cruising guide and Navionics’ own crowd-sourced chart overlay, a third route is revealed. Note that it crosses another mudbar, except that this one does not exist.

CROWD-SOURCING RIVALRY

ActiveCaptain and Navionics are rivals in the crowd-sourcing game — along with a more rigorous initiative than either called ARGUS, which stands for Autonomous Remote Global Underwater Surveillance. ARGUS is a patented system for harvesting time-stamped and position-tagged soundings, which can then be displayed in navigationally useful ways.

The theory behind ARGUS is that a “black box” installed in commercial or recreational boats automatically submits the data to ARGUS servers, when in Wi-Fi range, without any involvement by the boaters themselves, thus diminishing the possibility of human error. I say “more rigorous” because ARGUS relies on carefully calibrated sounders and computer algorithms that take into account the state of the tide.

The ActiveCaptain commentary for the area in question showed the way. The most recent post was in June, just a few days before our own transit.

The ActiveCaptain commentary for the area in question showed the way. The most recent post was in June, just a few days before our own transit.

ActiveCaptain is incorporated in nearly everybody’s cartography and PC navigation software — Furuno, Garmin, C-Map, MaxSea, Nobeltec, Coastal Explorer and others. The most notable exception is Navionics, which has gone its own way with its Freshest Data initiative. ARGUS results are posted on the online charting enterprise EarthNC and the Salty Southeast Cruisers Net, with which it partners.

The magenta line is hugely popular among boaters, most of whom know enough not to trust it as an indicator of adequate depth. They appreciate it, however, because among the often labyrinthine system of rivers and creeks and canals it provides an easy indicator of the ICW’s path, which is not always obvious absent the line.

A NOAA REDO?

One option, Forsythe says, is that NOAA would re-survey all 1,244 statute miles. She said NOAA has six navigational “response teams” checking the accuracy of charts in high-traffic area such as ports. “Maybe we just pull these guys in and have them spend a summer just doing the Intracoastal, or maybe we should go outside and hire someone,” she says.

If those NOAA response teams are sent down the ICW, they will be following in the wake of thousands before them. Although the magenta line first appeared on charts in 1912, it was not until the 1930s that it began to resemble the route we see on charts today.

A surveying team establishes the “best route” on the ICW in Florida during the 1930s.

A surveying team establishes the “best route” on the ICW in Florida during the 1930s.

In 1935, at the height of The Great Depression, NOAA’s predecessor agency received an additional $5.1 million, more than tripling its annual $2.2 million budget. The idea was to put people to work, so the money was used to hire more than 2,500 new workers, most of whom were to perform field work. Fourteen crews were assigned to what was then called “The Inside Route” from New York to Corpus Christi, Texas. The result was essentially the magenta line of today.

A NOAA redo would be the best possible outcome, but the agency is cash-strapped and mandated to focus on commercially important waterways. But there is evidence that the agency is adopting a more innovative posture than we have come to expect. Behind the scenes there is a great deal of discussion among all of the players in the marine mapping world. And it’s worth noting that ActiveCaptain already has a route-sharing feature that might suggest a solution for electronic charts.

NOT GOOD ENOUGH?

I randomly checked one of the ActiveCaptain shared routes through Crooked River, and it looks as if anyone following that line would have gone aground like me, suggesting that the authors of that particular route benefited from a combination of shoal draft and high tide.

This, however, does not refute the concept, but does underscore the advantages of the ARGUS system, which would be my second choice if NOAA could not afford to revisit the ICW itself. In fact, the initial research that began the ARGUS project was partially underwritten by a NOAA grant, even though ultimately NOAA judged that ARGUS results did not meet its high standards for precision. To which I would say, “The perfect is the enemy of the good.”

ActiveCaptain and Navionics, however, have an advantage over ARGUS in that they represent successful business models and (sometimes bitter) rivals for crowd-sourcing pre-eminence in the world of marine charting. Both organizations are no doubt brainstorming a solution as you read this.

The second decade of the 21st century is an interesting time to be a map junkie. Cheap GPS, connectivity and the Internet are turning the once top-down world of map making upside down as government takes a back seat to us, the geo-enabled masses.

Meanwhile, please tell NOAA what you think by commenting for the Federal Register. You have until Dec. 26.