Monday, December 31, 2012

The complicated business of draining the continent

Yesterday afternoon I went downtown and paddled for 60 minutes on a cold but calm day.  The river level was 10.9 feet, the highest Memphis gauge reading since last May.  Even though this level is on the low side of medium for this time of year, it felt very high, with the water covering parts of the landscape that had been high and dry for months.

The Mississippi River has been in the national news lately because its low levels have threatened the smooth flow of barge traffic, and so some readers might be surprised to hear me say the water is up here at Memphis.  But the Mississippi is a long river, and Memphis is not where the current news-making problem is.  That distinction belongs to the section between St. Louis, Missouri, and Cairo, Illinois.  Above St. Louis, the lock-and-dam system on the river is pretty reliable for keeping the river at adequate depths for commercial traffic, and at Cairo the Ohio River comes in and increases the Mississippi's flow capacity by about 200 percent.  Months of drought conditions in the watershed of the Missouri River (which reaches the Mississippi just above St. Louis), combined with frozen water in the upper reaches of the Mississippi, have resulted in a scarcity of water from St. Louis down to Cairo, where the Ohio provides relief.

Fairly often I find myself explaining the river's behavior to people in other parts of the country, and even to people right here in Memphis who just don't pay much attention to the river.

Back in 1993, when footage of the devastating floods on the upper Mississippi dominated the national news on TV, there was some wailing here in Memphis over our impending doom.  But that was all wasted breath, because below-normal flows on the Ohio that summer meant that the lower Mississippi's riverbed had plenty of room to accommodate the water coming down from the upper Midwest.

When we have had heavy rain here in the Memphis area, I sometimes hear the question "Has all this rain brought the Mississippi up?"  The answer is always no.  Local rainfall does bring up our small rivers, like the Wolf.  But even an enormous infusion of water from the Wolf is not enough to make a noticeable change in the Memphis gauge reading on the Mississippi.  Wolf River water does, however, combine with flows from other area tributaries like the Loosahatchie River and Nonconnah Creek to affect Mississippi River levels farther downstream.

The most appalling display of local ignorance of our river's ways occurred in May of 2011, when the river rose to the second-highest level ever recorded at Memphis.  Before the floodwater had even arrived here, I had a conversation with a conspiracy theorist who claimed that the government was holding back information and that anything and everything near the river was liable to be washed away at any moment.  I calmly explained that flash floods don't happen on the Mississippi and that flows are entirely predictable based on precipitation data from higher up in the watershed.  But the guy didn't seem convinced.  Then came the flood, and with it a caravan of national network news trucks, and suddenly hundreds of people who had never before given the river five seconds of thought were experts on our continent's grandest waterway.  One of the worst was Bob Nations, our local director of emergency preparedness, who might really know his stuff when it comes to tornadoes or earthquakes but clearly had no idea how the Mississippi River works.  Many other people were so thoughtful as to lecture me on why I should never, ever go near the river with a kayak at any level.  Even in the best of times I have a tendency toward misanthropy, so in the interest of personal sanity I had to close my eyes and try to shut out all the misinformation swirling around during the Great Flood of 2011.

Most of the time, thankfully, I am able to do my thing on the river without attracting much attention.  As the song goes, the Mississippi "just keeps rollin' along," through times of flood and times of drought and everything in between.  And as long as I'm able, I'll keep paddling my boat out there, getting my exercise and enjoying the natural wonders of the place.  Happy New Year.

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