Sunday, December 7, 2014

Crounse Week, Day 2: Math and coal barges

So, Crounse boats push barges. It's what they were built to do. One thing Crounse does is get every foot of coal on its barges that it can.

Like this one that I saw a Crounse boat pushing out of the Kanawha last year. It gives a scale of how big those things are and how much coal is on them.

Before that, I did the math on how you can estimate the amount of coal a barge carries.

If you look at the waterline, you see the number "10". The water is at the bottom of the "10", meaning it sits 10 feet deep in the water, or draws 10 feet, or however you want to say it. The numbers are six inches high, and there are six inches between consecutive numbers, so you can estimate to an inch or two how much water the barge draws. (Thanks for the information, C.R. Neale.).

If you click to the above-mentioned link, you'll see barge C411 was drawing about 10 feet 6 inches that day.

On its web site, Crounse provides charts to let you know how much tonnage its barges haul if you know how much water they draw. When you get to 9 to 10 feet on barge C862, an additional foot of coal is about 211 tons. Barge C411 can run deeper. The difference between 9 feet and 10.5 feet is 299 tons. Pushing an extra foot of coal per barge on a 15-barge tow is the equivalent of adding nearly two barges.

That helps when tow sizes on the Ohio are mostly restricted to 15 barges each because that's what the locks were designed to handle. The locks allow boats to pass through the dams, which are there to ensure the minimum 9-foot navigation channel.

Sometimes towing companies will experiment with oversize barge tows. Adam and I once saw a Crounse boat pushing 25 barges up past Greenup, Kentucky.

One thing about barges that sit that low in the water:

They tend to splash a lot. So if you have to go out on the head of a tow like that, prepare to get wet.

In the winter, that water freezes and forms a thick layer of ice on the barges. I'm glad I'm not the guy who has to go out and chip that stuff off, assuming they do that.

P.S. In case you're wondering, all Crounse barges are identified with the letter C and a three- or four-digit number. Each company follows a similar convention. Ingram barges begin with ING, Campbell Transportation with CTC and so on.

Next: Three generations of Crounse boats

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