Thursday, February 26, 2015

The Mississippi River Fascinates

How long is the Mississippi River?  That’s something of extreme interest to anyone wanting to paddle its full length, but it’s hard to get a firm grasp on a set number of miles.  Since the river is constantly changing, the first issue is how old the measurement is that one is quoting.  Then there are a lot of cut-offs and side channels, so did the person we are quoting measure the shortest distance, or the center of the shipping channel?  According to Jim Lewis’ research before his trip, the length of the Mississippi is listed at 2,552 miles by Itasca State Park, at 2,300 miles by the U.S. Geologic Survey, at 2,300 miles by the EPA, and 2,350 miles by the Miss. National River & Recreation Area office.   So, pick the number you like, or don’t worry about it.  As Pooh pointed out, “Rivers know this: there is no hurry.  We shall get there some day. “ 
The river doesn't just flow from north to south, but hits every degree of the
compass in between.  If you look at the scars in the forest, you can see where
the river used to be before cutting new channels.

Actually, if you paddled the river twice, you’d undoubtedly come up with two different measurements.  The river will frequently find itself winding in and out among a number of islands, thus creating three or four different channels of different lengths.  As one channel goes fairly straight, another makes a bow, and a third takes off on its own and creates a huge dog-leg.  All the channels eventually take you to the same place, but how you travel between A and B to get there can give new meaning to the expression about “the long and short of it.”  If a figure is incorrect, no worries.  Like fashion, the old measurement may again come in style.

Called oxbows because of their shape, the river creates a loop, but erosion
makes the throat smaller and tighter until the river just cuts the old channel
off and leaves it behind to create another oxbow elsewhere.

The Mississippi is huge.  Its drainage basin covers 1,250,000 square miles of North America.  The river slithers and creeps about to make new channels, cuts off ones it no longer has use for, while at the same time carrying 500 million tons of soil into the Gulf of Mexico each year.  That is enough to extend the length of Louisiana 300 feet further south per annum.  Mark Twain wrote that a man can go to bed in the State of Mississippi, and during the night an oxbow can break through, and he will wake up to find himself in Louisiana.  Waterfront towns that built themselves on the commerce of the river have found before long that they were country farm towns with no access to the river at all.  At other times, such towns would be swallowed to become part of the river.  Nearly all of the Mississippi River that LaSalle paddled in the 1660’s is now dry land.  Twain wrote of the town of Delta, which at one time was three miles south of Vicksburg, but after some reworking of the land by the river, was two miles north of Vicksburg. 

This is the Clark Oxbow, south of Palisades, MN.  The yellow follows the
new river channel.  When reaching the fork, if you followed the wrong channel
you would be taken miles out of your way.

This is the Maydale Oxbow.  Except for a small cut, the throat has been
completely cut off, making for some great day paddles through the forest
and out of the current.  Older oxbows are visible with four old channels
being visible in the same area.

Here you can clearly see how the oxbow is created.  Like annual rings in a tree,
you can see the concentric lines around the bow.  Each represents a heavy flow of
water from storms or spring run-offs where the outside bank is cut away, and eddy
currents fill land back in on the inside of the bends.

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