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I’m back and–before catching up on my time off the internet–I need to pack the robots back into Cosmoline and close out some January 2016 dredging business . . . here’s my most recent Professional Mariner article. And below are some additional photos of the research done in June 2015.
This is what 1100 + cubic meters of misplaced river bottom looks like after it’s sucked up and being transported to another location where scour demands it be added.
And that red boat in the distance is the client, at least the
verifier for the client.
Once in the designated discharge site, hydraulic ram start to press the
hulls apart, and
all that bottom finds itself in gravity’s grip and
tumbles out.
Now only some water remains as the vessel–Ocean Traverse Nord–returns to the worksite and
lowers the arm to suction up another 1100+ cubic meters
of gallivanting silt piles, here shown in patches of green. Notice the darker rectangle, representing the location of the dredger hull.
All photos by Will Van Dorp.
For video, click here and start at 13:51.
Aug 31. A late summer day at the beach, where a new “towel drying rack” has been adopted and a bumper crop
of sand awaits the erosion of winter, perhaps? All photos here taken by Barbara Barnard.
Sept 1. A tug (Trevor?) moves a crane barge to where the “drying rack”/piping needs to be fished out for transport to the next job.
Sept 13. The remaining pipe on the beach, no longer serving to dry swimmers’ towels, awaits dismantling and
allows for closer inspection.
This Rockaway series was of course motivated by Hurricane Sandy and the photos of Rockaway by my friend Barbara in the past 12 months. Barbara, many thanks. Here was my Nemo to Flag Day post, which started with a mystery house.
And now it looks like the Nola “make it right” rebuilding plan is coming to the Rockaways. Click here for the design for “resilient house.” Here’s an earlier article.
Click here for a project/business entirely created by the devastation of trees during the storm. It’s not maritime, water, or even specifically landthreshold related, but is quite interesting.
Here’s where the “leverman” sits for a twelve-hour shift as the C. R. McCaskill slews port to starboard 400′ once each three and a half minutes. Another way of saying that is the dredge moves using a five-point mooring system: two swing anchors, two breast anchors and one stern anchor to move forward or back. A different configuration uses a spudded idler barge; in this case, the “swing” is longer and takes more more time. Food gets delivered so that the leverman aka dredge operator can monitor all these screens and respond so that dredging can proceed 24/7 as long as equipment and conditions permit. More on food later.
Slewing . . . drawing on cables attached to positioned anchors and pivoting on a stern point . . . requires that the 30” diamater hose be able to flex. Hence, the easy curved slack before the piping to the beach.
The crewboat in the distance alternates between hydrographic survey work and other tasks. More on that in a moment. More crewboats in a future post.
Attachment at the stern is a ball and socket joint . . . like your hip.
Here’s the starboard GE engine, part of the power supply to the dredge.
Here is another view of the two huge hull-mounted pumps that do the work.
Another task of the crewboat is illustrated here: recreational boaters sometimes allow their curiosity to override any sense of danger caused by a busy, slewing dredge.
The helicopter happened to be here on assignment to photograph the work from the air.
About the food, here’s mission control presided over by Edwina Arthur, a member of the 30-50 person crew.
Food rules and pecking order are clearly posted.
Captain Randy Guidry, my host for this tour, proudly displays the builder’s plate, Corn Island Shipyard in Indiana, where the hull was constructed.
As I stated in the previous post, McCaskill’s part in the dredging/beach replenishment has now ended and vessels and crew have moved south for the next job.
Many thanks to Captain Guidry, Jan Andrusky, and all the other fine folks at Weeks Marine for this tour.
All fotos, text, and (any inadvertent errors) by Will Van Dorp.
Here and here are previous posts on a Rockaway Beach replenishment dredging operation that has now ended. Sea Wolf is still local, but the vessel on the horizon (“atop” the red buoy) has now moved to southern NJ. Remember, for most fotos, doubleclick enlarges.
Weeks’ Trevor was assisting in this project.
Also assisting was George W.
But here’s the powerhouse, the dredge. Let’s take a tour.
In spite of about 16,000 total horsepower, C. R. McCaskill is not self-propelled. To see what towed the dredge to the south, see the foto at the end of this post. All that power moves the cutterhead on the submerged arm (called a “ladder”) that extends to the sand at the bottom of the Channel here. At the top end of the ladder are two huge pumps (you could stand inside the pump housing) that suck the sand and whatever else off the bottom and send it as a slurry to a point on the beach some miles away. Click here for a pdf that shows the beautiful (ok . . . roll your eyes) virgin red cutterhead with green teeth. Each tooth weighs around 35 pounds!
Here inside the dredge are some interesting astounding facts about the machine.
See the sand colored building on the horizon off the stern of McCaskill? That’s the area around 105th St. Rockaway Beach where the sand is headed through piping powered by this vessel. The first few fotos in this post were taken at that beach. There’ll be another Rockaway post soon.
Candace towed C. R. McCaskill south. I missed her when she was in town, but John Skelson caught her here. Click on the foto to see John’s complete shot. Many thanks to John for use of that shot from his Flickr page.
All fotos by Will Van Dorp, except for the one shared by John Skelson. For more info on each of the Weeks tugs, click here. More McCaskill tomorrow.
Note: doubleclick enlarges almost all fotos for the past year or so.
Cutter head, the helical jaws with scores of teeth that need intensive maintenance,
light therapy to effect the endless gnawing away of
sixth boro bottom limits. One team attends to the teeth while another
elsewhere in
the Channel. I wonder when any of the Museums in other five boros will mount an exhibit of this effort, as the Boston
Museum of Science did 0f their herculean effort almost two decades ago. Meanwhile, what has happened to the cutter head, you say?
Or the mighty Brazos and crew?
Why . . . busy, of course.
All fotos by Will Van Dorp.
Vessels besides Florida include Sea Bear, Layla Renee, and Pearl River.
Whatzdis!?
A weapon from Captain Nemo’s Nautilus emerging from the depths to exact revenge?
Of course, if you read tugster regularly, you know about my fascination with the dredge machine called a cutter suction head. Tug supporting the dental barge here is Sea Bear. Note the condition of the teeth (over 50?) on the head and the green spares on deck behind the dental crew, who like the folks that work on human teeth, use
appropriate tools to assess the damage.
Reinforcements move in. This cutter head has been chewing on some hard and fibrous–if tasty?– sixth boro bottom.
When needed, the crew puts the heat
applies blunt persuasion, reminding me of the dentist who once exerted himself so much to yank a molar from my head that he broke
a sweat. An hour later, cutter head has a new set of beautiful green teeth, and Dr. Sea Bear
Interesting work, guys.
All fotos by will Van Dorp, who’s happy to see so much dredging happening along the Kills.
No matter that Padre Island might be the sixth boro’s version of Sisyphus . . . or an enormous vacuum cleaner/wet vac, no matter . . . I’m always happy to see the trailing suction hopper dredge (TSHD), especially up close. The northeast corner of Staten Island looks remarkable uninhabited, an illusion to be sure.
I guess this is the front dischange head. See a video of this attachments to this head used for “rainbowing” here. (Correction/crossout made here thanks to SeaBart.)
Here Padre Island heads out toward the Verrazano Narrows. I’ve wondered sometimes whether it uses its sonic eyes to make the “bottom of the harbor” equivalent of crop circles in the fluff.
Not the best foto, but the black structure is a drag head, attached to
the suction pipe, like arm and hand. See a trove of dredge images here.
Pipes and heads are stowed here, up and out of the way, as Padre Island travels to the area needing
to be carved or aspirated. I get dizzy thinking of all the potential jokes here, like “This job/boat sucks.”
As she passed by this week, I was surprised how much noise came from her 3000 hp propulsion. And how speedy she was. Was there ever sail-powered dredging? What artifacts get sucked up and dumped during the dredging process? I know progress calls, but what stuff otherwise treasured gets missed? What fauna gets sucked up? Was Oliver Evans‘ steamer Oruktor Amphibolos, “Amphibious Digger,” really the beginning of dredging?
All fotos Will Van Dorp.
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