Layers: Red River Valley, Grand Forks, ND

The Red River flows northward between Minnesota and North Dakota.  The land there is flat – very flat. This is prairie land turned into breadbasket.  It’s “north country,” with long, brutal winters and heavy snowfalls.  The bitter cold slides down the river valley from the even colder lands from Lake Winnipeg far north into Canada.  Even as winter frees the southern reaches of the river, the northern sections remain frozen.  As snowmelt and broken up ice flow north they encounter barriers of ice jams and the river begins to overflow.  Floodwaters spill over flatness, sometimes covering up to 30 miles either side of the river channel as farmland, and frequently the towns on the river, are inundated.  Grand Forks is one of those towns.

LAYERS-Red-River-Valley-Grand-Forks.-40x96inA river floods when its water overflows its banks onto land.  Some floods are caused by rain from a hurricane or tropical storm; a slow moving, high precipitation supercell thunderstorm which drops large amounts of rain, or a cluster of thunderstorms that don’t move much and keep dumping rain in one place.  Snow melt, a dam or levee failure, even a high tide moving inland, can cause flooding. Floods are probably the most commonly encountered natural hazard.  Rain falling on the land seeks its way to the sea by converging into ever increasingly large channels.  The rivulets of water cut the channels and temporarily fill the places water doesn’t flow swiftly enough to keep water-carried sediments from falling to the bottom.  Channels are created through this cutting and filling.  It is nature’s most common balancing act, especially where large amounts of rain fall or in deserts, with very infrequent rain.  Occasionally, once every few years, the water over tops the banks and havoc ensues.  This was what happened with the Red River in1997.  A catastrophic flood only expected to occur with a reoccurrence interval of 500 years,

The flooding in 1997 was severe.  “The worst flooding in over 100 years,” proclaimed the mayor.   It was worse than the 1897 flood that was 4 feet less.  The river carried more than 20 times its usual discharge. In the top ten flood events even the crest of the 10th worst was only about 9 feet lower.  Millions of dollars lost.  Lives and livelihoods lost.  Millions spent on rebuilding.  Millions spent on flood control structures, the latest reminiscent of the scheme Leonardo Da Vinci and Nicolo Machiavelli hatched to reroute the Arno River to deprive neighboring Pisa of its water.  The current plan to reroute the Souris and Red River in times of high water will defend Minot, Grand Forks and Fargo from flood waters by diking and rerouting flood waters north to Canada.  And what about our Canadian friends in Winnipeg?  They have already dug a rerouting “ditch” around the most vulnerable parts of their city.  One would think that all this experience with flooding and all the money spent on defensive measures would eventually bring about a river tamed.  Not so!  As the list of historic crests indicates things are definitely not getting better.

HISTORIC CRESTS

  1. 54.35 feet – April 22, 1997
  2. 50.20 feet – April 10, 1897
  3. 49.87 feet – April 14, 2011
  4. 49.34 feet – April 1, 2009
  5. 48.81 feet – April 26, 1979
  6. 48.00 feet – April 18, 1882
  7. 47.93 feet – April 6, 2006
  8. 47.41 feet – April 16, 2006
  9. 46.00 feet – March 20, 2010
  10. 45.93 feet – April 21, 1996

Source: National Weather Service

They are getting worse.  Of the last ten major flood events, all but two occurred in the last fifteen years.  The twenty-first century has seen half of them!  One might speculate about the problems with flood control structures (they often fail in big floods) causing this recent rise in catastrophe.  One might also look at increased building on the flood plain with more and more people and less and less permeable ground.  One might consider changes in weather patterns associated with climate change.  What remains a mystery though is why the people remain in dangerous locations with this kind of recurrence.  This is a question that one might ask for any of the places studied in Layers!

Text prepared by Dr. James Brey

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Layers: Places in Peril

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