Sunday, February 28, 2016

Updated Charts

A couple of years ago, when I took an assessment, part of it included some basic navigation. The other candidate was asked to locate where we were on a chart, and then to identify a buoy.

He pointed at one, and the assessor shook his head. Later on though, we had a bit of fun trying to find that buoy. It wasn't on any of our charts!

The buoy is off the northwest corner of Governors Island in New York Harbor. Here is a picture from my paper chart:

The Paper.

A year or so ago I bought an app for my iPhone (iNavx, also available for OS X). This downloads maps from NOAA, and so can be more up to date.


There it is: Green #1.

So, the next most obvious question is, what is it doing there? It's green, so marking the right side of the channel to see - but that doesn't make sense if you've coming down the Hudson to see, because the buoy would be to your left.

My theory is, it's to keep traffic from the East River (to the right and up on the images above) farther out from the Statue Cruises at Battery, and also wide if they're coming around Battery - that area can be something of a blind corner.

I actually contacted the Coast Guard, and got the following response - more or less confirming my theory, with a little more detail. Apparently this is a newly marked path that replaces Deep Water Range - if I read my old chart correctly, that dashed line from a flashing light on one of the Brooklyn piers to Green 35, east of Ellis Island.

"Good Afternoon [Kayak Cowgirl]  Deep Water Channel LB 1 (Light List Number 27350) is the first of three buoys (1, 2 and 3) that replaced the Deep Water Range that brought deep draft vessel into and out of the East river past Dimond Reef, north of Governors Island. LB 1 ensures that outbound vessels from the East River are past and clear of Governors Island before turning south. And it does help deep draft heading into the Hudson R avoid the 30 foot curve off the Battery."

If you look closely on that old chart, in my snapshot above, you can see what they mean about the "30 foot curve off the battery". There's a faint line kinda looping south and then east to include a 29' depth mark. The old chart marked a pretty generic path through the area. The newly-placed buoy basically marks the end of that bar - if you're a deep-draft vessel, you'd definitely prefer to keep to the left of it on the way out.

So, mystery solved. Charts, and the markers and channels they document, can change over time. Be sure to check for updated information before heading out to sea!

Update: On further review with a fellow chart enthusiast, we noticed that the old path - the dashed line indicating a range - was based on a straight line between flashing read markers at the northernmost Brooklyn-side piers and Green 35 near Ellis Island. And, the new channel is almost exactly that - draw a straight line through the new Green 1 and Green 3 buoys and the new Red buoy near Dimond Reed, and it's an exact match to the old range.

However, those markers are not on the new chart - are they gone, perhaps as part of the refurbishment of that waterfront?

So little had changed for vessels heading to and and from the East River and the sea, other than how they are marked, but my original hypothesis is supported - vessels making that corner 'round the Batter will want to know where the edge of that 30' bank is.