• The Mississippi: A Visual Biography by Quinta Scott

    "Great book and great blog - thanks for the first book I have seen that addresses the contemporary river, headwaters to gulf." Dan McGuiness, Audubon, St. Paul, Minnesota

    Click to order

  • Catagories

  • Archives

  • November 2017
    M T W T F S S
    « Oct    
     12345
    6789101112
    13141516171819
    20212223242526
    27282930  
  • Meta

New Madrid Floodway

Ten Mile Pond Conservation Area in the New Madrid Floodway

Ten Mile Pond Conservation Area in the New Madrid Floodway

How many times do we have to petition to stop the closing of the New Madrid Floodway? Once again its closure in on the agenda. Find the petition here: http://org2.salsalabs.com/o/7288/p/dia/action3/common/public/?action_KEY=23677.

Please sign.

If you do a search for New Madrid Floodway in the search box, you will find all my postings on this subject.

In the meantime read this from 2013 if you want to understand how the floodway came about, its importance for flood control on the Lower Mississippi, and importance to places like Ten Mile Pond and Big Oak Tree State Park.

It’s baaaack: The closure of the foot of the New Madrid Floodway is back on the agenda of folks who farm the floodway and see there land flooded every year the Mississippi Floods. If you remember, two years ago the floodway was opened to provide extra storage capacity for the flooded Mississippi. But every time the river floods water backs up into the floodway at its foot.

It seems that Senator Roy Blunt is pressuring the Obama Administration to go forward with the closure of the floodway by putting a hold on President Barack Obama’s nomination of Gina McCarthy as head of the Environmental Protection Agency (EPA).

I cut the following essay from The Mississippi, because the issue had been resolved in 2007 when U.S. District Judge James Robertson of the District of Columbia ordered the project halted and the work already accomplished dismantled. It had not. Soon after the Memphis District of the US Army Corps of Engineers began working to satisfy the court’s objections to the closure of the floodway. However, the U.S. Fish and Wildlife Service and others who object to the project or no more satisfied with it as it stands now than they were when the judge ruled in 2007. These things never go away. This link will help you understand where the project stands now.

The following is the full story as it stood in 2007:

The St. Johns Bayou-New Madrid Floodway Project

In 1928 when General Edgar Jadwin and the Corps of Engineers designed the New Madrid Floodway, the agency left a 1,500-foot gap at the foot of the setback levee for the release of floodwater and installed a fuse plug levee at Birds Point at its head. The designers understood that the lower third would become a backwater storage area. To compensate landowners for the use of their land, the agency purchased flood easements in the upper two-thirds. That wasn’t necessary in the lower third, which would flood with the river every time. It was the floodway’s role as a backwater storage area that created an uproar at the beginning of the twenty-first century, when the Crops published its plan for the St. Johns Bayou-New Madrid Floodway Project, which promised to eliminate backwater flooding in the New Madrid Floodway.

The Water Resources Development Act of 1986 authorized the dredging of St. Johns Bayou for flood control, the St. Johns Bayou Pump Station, which included a gated culvert across the foot of the bayou, and the New Madrid Pump Station and a gated culvert set in the 1,500-gap in the setback levee of the New Madrid Floodway. St. Johns Bayou Basin is located between the setback levee and Sikeston Ridge. The gated culverts would halt backwater flooding from the river, but assure interior flooding in both St. Johns Bayou basin, located between the setback levee and Sikeston River, and in the New Madrid Floodway. The pumps would clear water ponding behind the closed culverts. The culvert across St. Johns Bayou was built. In 1997 the Memphis District of the Corps of Engineers filed its intent to prepare and environmental impact study of the project.

Environmentalists, river conservationists, the Environmental Protection Agency, the U.S. Fish and Wildlife Service, the Missouri Department of Conservation, the Missouri Department of Natural Resources, and taxpayer watchdogs: all objected. They balked at closing the last connection the Mississippi had to its floodplain in Missouri, at the $65 million cost, at the damage that would be done to Big Oak Tree State Park, at the loss of spawning habitat for fishes and wintering places for waterfowl, to the channelizing of St. Johns Bayou and other drainage ditches. They complained that the project would benefit a handful of big landowners. They noted that East Prairie in the St. Johns Bayou Basin would continue to flood due to runoff from roofs and parking lots. They encouraged the Corps to find non-structural solutions to the flooding problems, including a ring levee around East Prairie.

The East Prairie Enterprise Community, the local sponsor of the project, and other residents of Swampeast, weren’t interested in environmentalists’ concerns. East Prairie residents complained that a ring levee would cut them off from the rest of the world. Farmers gave little support to the Wetland Reserve Program. They had rejected a 1993 U.S. Fish and Wildlife Service offer to purchase land in the St. Johns Bayou basin for a national wildlife refuge at fair market value. Nor were they interested in converting their lands from crops to timber.

In September 2000 the Memphis District sought to please both the environmentalists and the residents of Mississippi County when it revised its plan. The floodgate and the pumps would stay, but the following changes would be made: the Corps would dredge only the St. Johns Bayou-St. James Bayou drainage ditch, reduce its width from 200 feet to 120 feet, and excavate only one side to avoid cutting into forests. The engineers would not dredge the upper 3.7 miles of St. James Bayou Ditch to avoid the habitat of the golden topminnow, a state endangered fish; would avoid mussel beds or relocate them and set up a ten-year monitoring program. They would set rock structures in the channels to enhance fish habitat; move water in and out of the lower reaches of the floodway and the basin for winter and early spring waterfowl and to allow spawning fish to pass to and from the river; purchase conservation easements on 765 acres of herbaceous land along the channel to replace shorebird habitat; reforest 9,557 acres of seasonally flooded cropland. At Big Oak Tree State Park they would build a control structure to regulate water in its swamps–enough for the cypress, but not too much for the oaks.

Big Oak Tree State Park

The Corps published essentially the same plan in June 2002, but added the construction of the wildlife corridor between Big Oak Tree Park and the Ten Mile Pond conservation area and riparian buffers along sixty-four miles of streams and drainage channels to filter water flowing to Big Oak Tree. Most important, the engineers made the commitment to the restoration of Big Oak Tree, purchasing and reforesting 1,800 acres surrounding the park and restoring the park’s hydrologic connection to the Mississippi with water control structures in the park, a canal with gated culverts set in the mainline levee to allow water to flow between the park and the river. The cost of the new plan came to $85 million dollars and still did not satisfy the Missouri Department of Natural Resources, the owner of Big Oak Tree Park.

In 2004 the Memphis District issued a contract for the construction of the New Madrid closure and the pump, but stopped work on the project when National Wildlife Federation and the Environmental Defense Fund filed suit in Federal Court, alleging violations of the Clean Water Act.

In December 2005 the Corps published a second Revised Supplemental Environmental Impact that would allow fish to spawn in the sumps behind the culverts and would reestablish the hydrological connection between Big Oak Tree and St. James Bayou through a culvert in the levee.

The Corps pointed out repeatedly that the success of the project depended on finding people willing to sell their land for mitigation to add 1,800 acres to Big Oak Tree State Park or the addition 1037 acres needed for the wildlife corridor and riparian buffers.

In the fall of 2006 the Corps of Engineers started work on the project, even after being told they would likely lose the Federal suit filed two years earlier. The suit came to fruition in September 2007, when U.S. District Judge James Robertson of the District of Columbia ordered the project halted and the work already accomplished dismantled.

 

Advertisements

Tough Times on the Mississippi. Maybe not so tough.

The Coast Guard closed two sections of the Mississippi over last weekend, where barges broke loose at St. Louis and Vicksburg, rammed bridges,  and then sunk.

Thursday we had 4-5 inches of rain in Monroe County, Illinois at the east in of the Jefferson Barracks bridge, which was hit by one or more barges early Sunday morning. All that water poured into the Mississippi, causing the first flooding since the fall of 2011. This morning the flood gauge at St. Louis hit 35 feet, five feet above flood level, the highest it has been since 2008. The Coast Guard reopened the river this morning, It seems the sunken barges will cause no harm to navigation and the stranded barges are outside the navigation channel.

The Jefferson Barracks Reach of the Middle Mississippi, July 2012.

The Jefferson Barracks Reach of the Middle Mississippi, July 2012.

At Jefferson Barracks the Mississippi is wide and shallow and has caused the Corps of Engineers no end of trouble since the first began deepening the channel to 9 feet in 1872. Last summer the drought was so severe and the river at Jefferson Barracks so shallow that sandbars were forming between the dikes.

The Jefferson Barracks Dike Field, St. Louis Harbor

The Jefferson Barracks Dike Field, St. Louis Harbor

Upstream of the Jefferson Barracks Bridge the dike field was exposed so long that vegetation took root and got a pretty good start before flooding came along and washed it away.

 

Lower Reach of Jefferson Barracks Chute

Lower Reach of Jefferson Barracks Chute

Last summer the side channels almost dried up. This spring flooding has filled them and flushed out excess sediment. Fish will be able to find quiet places to spawn.

Low Water on the Mississippi and Thebes Gap

Thebes Gap:

Alexander County, Illinois

“Here is a vast ledge of rocks, which stretch across the river in a direct line. The best channel in the middle of the river, in which place in low water, there is not more than six feet over the rocks.”–Zadoc Cramer, 1814

Rock Formation in the Middle Mississippi at Thebes Gap, 2006

Rock Formation in the Middle Mississippi at Thebes Gap, 2006

The Mississippi is running very low. After the Flood of 2011, the river drained away very quickly and the rain stopped. By the Summer of 2012, we in the Midwest were well into the Drought of 2012 and the river was showing the effects. Now in January 2013, the Upper Mississippi is frozen and the system of locks and dams is retaining water north of Alton, Illinois. On the Missouri a similar system of dams is retaining water in South Dakota and too little water is flowing into the Mississippi to maintain water levels for the 9-foot navigation channel on the Middle River.

Look at any aerial photograph of the confluence of the Missouri and Mississippi. The muddy Missouri spews a flume of silty water into the relatively clear Mississippi. They flow side by side downstream--the Missouri on the west, the Mississippi on the east--for several miles. During the very cold winter of 2000-2001 it was possible to see this phenomenon from the Illinois bank near the spot where Lewis and Clark started their journey up the Missouri: Lock and Dam 26 at Alton trapped ice coming down the Mississippi. South of the dam the river flowed free of ice, but ice did flow out of the mouth of the Missouri. At the confluence the two rivers, the icy Missouri and the ice-free Mississippi flowed side by side in the Mississippi channel.

Look at any aerial photograph of the confluence of the Missouri and Mississippi. The muddy Missouri spews a flume of silty water into the relatively clear Mississippi. They flow side by side downstream–the Missouri on the west, the Mississippi on the east–for several miles. During the very cold winter of 2000-2001 it was possible to see this phenomenon from the Illinois bank near the spot where Lewis and Clark started their journey up the Missouri: Lock and Dam 26 at Alton trapped ice coming down the Mississippi. South of the dam the river flowed free of ice, but ice did flow out of the mouth of the Missouri. At the confluence the two rivers, the icy Missouri and the ice-free Mississippi flowed side by side in the Mississippi channel. In the Winter of 2013 too little water is spewing out of the Missouri to feed the Middle Mississippi.

 Thebes Gap is the geological break point between the Upper Mississippi and the Lower Mississippi. The Upper Mississippi flows through a rocky gorge from Minneapolis to Thebes Gap. South of there the Lower Mississippi meanders across an alluvial plain.

At the beginning of the glacial age, the Lower Mississippi flowed along the western valley wall through an alluvial floodplain in the Western Lowlands along the Black, White, and St. Francis Rivers.

From The Mississippi: “Geologists have speculated that the river abandoned its alluvial valley and diverted through Thebes Gap, a narrow bedrock canyon in the Benton Hills, through the series of glacial floods at the end of the Wisconsinan age. At the beginning of the twenty-first century, seismologists questioned why the Mississippi would abandon its comfortable alluvial valley to ream a new course through bedrock. They noted that fault lines in the Benton Hills were active 10,000 years ago, and speculated that an earthquake along fault lines in the Benton Hills opened the canyon that is Thebes Gap. Glacial River Warren, which broke out of a glacial lake that covered northern Minnesota and North Dakota and reached north into Canada,  thundered through it, and deposited a classical alluvial fan at the mouth of the canyon.”

 “Thebes at the head of the Grand Chain and Commerce at the foot of it were towns easily rememberable as they had not undergone conspicuous alteration. Nor the Chain, either–in the nature of things; it is a chain of sunken rocks admirably arranged to capture and kill steamboats on bad nights.–Mark Twain, Life on the Mississippi

Thebes Gap, where the Mississippi takes a wide turn into the narrow reach of Thebes Gap.

Thebes Gap, where the Mississippi takes a wide turn into the narrow reach of Thebes Gap.

Mark Twain knew Thebes Gap, and while it is no longer killing steamboats, this winter modern tows can’t get through this narrow gorge between the Upper Mississippi and the Lower Mississippi.

The U.S. Army Corps of Engineers have contracted with Newt Marine and Kokosing, a marine engineering firm out of Iowa and Michigan,  to remove the rocks from Thebes Gap. When they are done there on January 11, they will move on to Grand Tower.

A tow steams passed Tower Rock at the beginning of December.

A tow steams passed Tower Rock at the beginning of December.

The river level today at Chester, Illinois is -0.6 feet, which means it is possible to walk out to Tower Rock and see just how low the Mississippi is.


[i]             Cramer, 173; Harrison, Richard W., “Report on Investigations of the Benton Hills, Scott County, Missouri, in Midwest Friends of the Pliestocene, 42nd Annual Meeting, 19-21 May 1995, 7.3; Harrison, Richard W., “Mid-Continent Urban Corridor Mapping Project,” USGS Project No.: 7160-11, U.S. Geological Survey, http://erp-web.er.usgs.gov/reports/annsum/vol40/cu/harrison.htm; Elfrink, Neil, “Gujarat Analog Response,” Archives of Central U.S. Earthquake Hazard MailList, March 21, 2001, http://clifty.com/hazard/archives/1010302-021954.html; Guccione, Margaret, “Re: ‘Gujarat Analog,’” Archives of Central U.S. Earthquake Hazard MailList, Feb 16, 2001, http://clifty.com/hazard/archives/1010216-111758.html.

Drought, Low Water, the Middle Mississippi, Side Channels, and Fish

The Jefferson Barracks Reach of the Middle Mississippi, July 2012.

Starting in April, I spent the spring and summer working on the third of three articles on the American Bottom in Monroe County, Illinois for Confluence Magazine, published by Lindenwood University. The first, published a year ago, discussed the Hill Prairies and the bluffs that rise above the American Bottoms. The second covered the floodplain between the bluff and the river levees. This summer’s work was for the article on the land between the levees and the river and the side channels that flow between the islands and the east bank.

The side channels provide fish and waterfowl quiet places to breed and rest. Where they are deep, they provide fish with places to wait out the winter, when the river may be frozen, and wait out  a drought, when the channels may dry out. The Drought of 2012 was very hard the side channels and therefore on the fish.

Dead fish, mostly Asian carp, in the Jefferson Barracks Borrow Pit after the Flood of 2011

When I started in April, the coming drought was not really apparent yet. Yes, last year’s monster flood drained away very quickly, leaving fish stranded and dying the the borrow pits on the river side of the levees. But there was still water in the side channels that ran between the east bank and the islands. Occasionally, I would trip over a dead carp, washed up near the bank. The wheat was doing well. So were the baby soybeans.

The young corn looked okay, too, though it would suffer come July and August.

Wherever I came to the bank of the river, there was evidence of last summer’s flood in the dead willows that had been stripped of their leaves during the flood. And there was evidence of the growth of new vegetation. Even with the dry conditions, new growth wasted no time to set started once the soil warmed up.

River Mile 143, June 2012

To make the article work I needed to get to the side channels. Only the Fort Chartres Chute and Island are in public ownership. The rest are in private hands and required permission to get to them. Fortunately, two farmers allowed me on their lands, and one provided transportation to Calico Island. We rolled down the steep bank onto the bank of the side channel.When we arrived the first time, I put my camera to my eye and found the battery had died. I love pixels, but I hate batteries required to make them work. Fortunately, the farmer with the transportation was willing to have a go of it the next day. And it was serendipity, because when we went back, the river had dropped considerably overnight, and we were able to cross the chute, that was too deep the day before, and onto the island.

Still Wet Mud on Calico Island, July 2012.

As the river continued to drop the little inlets you see in the muddy bank above turned into small pools, in which fingerling fish were trapped.

When wer returned to the side channel, we discovered we had run over a catfish, a very large catfish, and rolled it up onto the bank.

Calico Island Catfish

In mid-July Calico Chute still had water in it, but our dead catfish told us it was growing shallower and shallower. Very small fish were trapped in pools that formed here and there in the mud.

A few weeks later I hiked out to the edge of Jefferson Barracks Chute. Its upper reaches were drying out, but the lower half carries Palmer Creek to the river and still held water.

Lower Reach of Jefferson Barracks Chute

I did not get to Chartres Island Chuteuntil late October and found only the plunge pool, downstream of the closing dam at mid-chute, filled with water. When I first hiked out to the chute in 2009, it was filled with water, both upstream and downstream of the closing dam.

Chartre Island Side Channel upstream of closing dam, 2009

This trip the upstream end of the chute was dry. A dense stand of willows, as tall as me, (5’6″) had taken root in most of the chute. Fish bones littered its dry bed just upstream of the dam, the last place that dried out.

A dead gar in Chartres Island Chute upstream of closing dam, 2012

Chartres Chute Plunge Pool, 2012

At low water, an arbitrary number set on the flood gage at St. Louis, the plunge pool downstream of the dam is ten feet deep and the only place fish can wait out a drought or, in good times, the winter.

 

 

 

 

 

 

 

 

Low water on the Mississippi and Missouri Rivers Threatens Navigation on the Middle Mississippi below St. Louis, Part 1

The Jefferson Barracks Reach of the Middle Mississippi, where the river is wide and shallow and causes the Corps of Engineers no end of headaches. July 2012.

We in the midwest have had a terrible drought this summer and even though we have had some rain since the beginning of August, that rain has not flowed to the Mississippi River. The river is very low and navigation is threatened.  And navigation on the Middle Mississippi depends on water flowing from the Missouri. Let’s start with the Missouri, which in normal years supplies the Middle Mississippi south of St. Louis with 60% of its water. This year the Mississippi has drawn 78% of its water from the Missouri.

Low water at the Confluence of the Mississippi and Missouri Rivers, between the west bank and Duck Island, 2009.

Governor Jay Nixon has asked the U.S. Army Corps of Engineersto trash its plan to reduce the amount of water it releases from 17,000 cubic feet per second to 12,000 cfs from the Gavins Point Dam in South Dakota in order to maintain water levels for navigation on the Middle Mississippi. He fears economic catastrophe is the Middle Mississippi River has to be closed to navigation for want of water from the Missouri.

Gavins Point Dam at Yankton, South Dakota

This morning, the flood gage at St. Louismeasured 0.1 foot, Over the next several days it is projected to go up, and down and then way down to -0.6 feet. Any closing could happen when the Mississippi reaches -5 feet at St. Louis.

The Middle Mississippi at Tower Rock just south of Perryville, Missouri.

When the gage at Chester, Illinois gets down to about 1 foot, it is possible to walk out to Tower Rock, just south of Perryville, Missouri. The gage at Chester was a 2.4 feet this morning, which means you cannot walk out to Tower Rock without getting your feet wet.

In the late winter and early spring and extending through the summer of 2003, the Mississippi was so low it was possible to walk out to Tower Rock, south of Perryville, Missouri. Once the flood gage at Chester gets down to about 1.0 foot, it is possible to make the hike.

Should the river fall below 5 feet at St. Louis the Corps of Engineers would consider blasting away rock formations in the bed of the river at Tower Rock and at Thebes Gap.

Update: On the bright side of the drought: with less water running off the land, fewer nutrients are making it to the river, and the dead zone in the Gulf of Mexico has shrunk this years.

The Flood of 2011 and the Atchafalaya Delta

“Artificial levees, extending clear to the Gulf of Mexico, may have made human habitation of the delta south of Cape Girardeau possible, but prevented the Mississippi from refreshing its marshes with its sediment when it did flood. Revetments built of concrete mats may have stabilized the navigation channel, but reduced erosion of the banks, a source of sediment in the marshes. James Eads’ jetties at the mouth of the river may have allowed the river to cut a thirty-foot navigation channel through the sandbar blocking the South Pass of the modern delta, but delivered sediment carried by the river to very deep water at the continental shelf, where it washed away, never to be used for marsh building. Closure of the old distributaries of the river may have prevented flooding in the bayou country of Louisiana, but cut the flow of Mississippi sediment to the coastal marshes. Channel dams may have made navigation on the Upper Mississippi profitable, but they retained its sediment north of Alton, Illinois. Dams on the Missouri, from which the Mississippi drew sixty percent of its sediment, did the same. In short at the beginning of the twenty-first century, the coastal marshes south of New Orleans received eighty percent less sediment than they had at the beginning of the twentieth and eroded away.”

I haven’t counted the number of posts I have begun with this quote from The Mississippiand I am doing so again.

Morganza Floodway Structure

Twice, 1973 and 2011, since it was constructed after the Flood of 1927, we have opened the Morganza Floodway Structure to release flood water from the Mississippi into the Atchafalaya River and Floodway. After the Flood of 1973, geologists noted that the Atchafalaya River was building land at its mouth, using all that mud funneled down the Mississippi from erosion from the Midwest and the South.

With this in mind geologists from the University of Pennsylvania–joined by others from the University of Mississippi, Louisiana State University, and the U.S. Geological Survey–began studying the sediment plumes that spewed out of the Mississippi, the Atchafalaya River and Wax Lake Outlet, and through the Bonnet Carre Spillway into Lake Pontchartrain during the Flood of 2011.

Sediment Plumes from the Atchafalaya, Mississippi, and Bonnet Carre

Atchafalaya Delta, 2009

The Atchafalaya slowly spread a wide plume of sediment in to Atchafalaya Bay, where it is building land. The Mississippi, which is too long and too flat and is hemmed between levees, is shooting its mud over the edge of the continental shelf, where it is useless for landbuilding.

Wax Lake Outlet Delta

Similarly, the Wax Lake Outlet, an artificial outlet from the Atchafalaya Basin, built to reduce flooding in the basin, is building its delta.

What is happening in Atchafalaya Bay is what happened naturally before we reengineered the Mississippi for flood control and navigation. Now that we have done it, we have to live with the consequences and find ways to restore Louisiana’s coastal wetlands by mimicking the river’s ways. The Atchafalaya is an example. So is the Mardi Gras diversion at Bohemia, which opened up into Breton Sound this spring during Mardi Gras.

The Mississippi Ridge at Bohemia south of the end of the main line levee

The question about the Mardi Gras Diversion is whether we are going to keep it or dam it. It is an example of what is being done on a small scale and can be done on a large scale along the Mississippi south of New Orleans.

Mississippi River Barge Traffic Slowed or Stopped near Greenville

 

 “Spanish Moss just below No. 82. This is a beautiful right hand bend forming three-fourths of a regular circle of about eight miles in length.

“The left had shore around this bend is clothed with willows and sand bars. Near the lower end of the bend the river in its highest state become much crowded together, not being more than a third of a mile in breadth, consequently very deep and rapid, and full of boils or swells, but no way dangerous.

“This settlement, of four small cabins, occupied by one Indian, one French, and two American families, having as many corn patches of three or four acres to each house, is at the right hand point immediately below the Spanish Moss bend, and a little above the head of No. 83. The bank here is pretty high, but I fear the overflowings of 1813 have destroyed all present attempts to continue the settlement. The peach tree leaves were green here on the 21st of December 1812, through the fall had been unusually cold and early, and the winter afterwards more severe than had been witnessed in 20 years.

“Just above the settlement you run nearly east, and three miles below it as nearly west.” –Zadok Cramer, 1814[i]

On Monday, August 20 a barge ran aground on the Lower Mississippi south of Greenville, Mississippi. The U.S.  Coast Guard closed the river to barge traffic, but reopened it 12 hours later to slow-moving southbound traffic, alternating with slow-moving north bound traffic, with the Coasties acting as traffic cop. There is history behind these problems at Greenville.

In the wake of the Flood of 1927, which drowned the Lower Mississippi alluvial valley from wall to wall, Congress authorized the Mississippi River and Tributaries Project in the Flood Control Act of 1927. The project standardized and raised the levees between Cape Girardeau, Missouri and Venice, Louisiana. It allowed reservoirs on the headwater tributaries of the Mississippi (Table Rock Lake on the White, Clearwater Lake on the Black, Wappello Lake on the St. Francis, all in Missouri; Arkabutla Lake on the Coldwater, Grenada Lake on the Yazoo, Sardis Lake on the Little Tallachatchie, and Enid Lake on the Tallachatchie, all in Mississippi) to retain flood waters in the uplands until the Mississippi could hold them. On the other hand, water released from the reservoirs during a drought can raise the level of the river. It created the New Madrid, Atchafalaya and Bonnet Carre Floodways (all used during last years flood) to siphon off floodwater, and in the case of the Atchafalaya and Bonnet Carre carry it to the Gulf of Mexico without ever returning it to the Mississippi. Finally, it authorized cutoffs across point bars to shorten the river and speed floodwater downstream. Therein lie our current problems on the Mississippi near Greenville.

The grey line follows the old Greenville Bends.

From the Mississippi: A Visual Biography Draft: Rowdy Bend, Miller Bend, Spanish Moss Bend, and Bachelor Bend: the river zigged and zagged between Arkansas City and Greenville, Mississippi. River pilots called them the Greenville Bends. They were shallow and meandered through erosion-resistant and cohesive clay. The Corps of Engineers worked for years to prevent the river from cutting new channels across the point bars that formed them, only to have General Harley Ferguson include them in his cutoffs to shorten the river and speed floods downstream.

Follow the thin blue line to understand the Greenville Bends and Point Bars across which General Ferguson made his cutoffs.

A meandering river works hard to maintain a fairly constant length. Natural cutoffs are its means. When the river becomes too long and its slope too flat, its searches out a steeper, more efficient slope. It makes a cutoff across the narrow neck of a point bar or by forming a chute across a wider part of the point bar. Once the river makes a cutoff, the speed and the slope of the river above the cutoff increase, it erodes its banks and its bed, adding to the load of sediment it carries. Below the cutoff the river remains unchanged. It moves slowly down a shallow slope, forcing the river speeding through the cutoff to slow down and deposit its sediment downstream of the cutoff, creating a new sand bar, around which the river will meander, restoring its length. In its natural state the Lower Mississippi made a cutoff once every seven to ten years. After it made a cutoff, the river took thirty to eighty years to recover and regain its width, its bar sequence, and its flow regimen.

Before Ferguson made his cutoffs, the average length of the Lower Mississippi River was about 1080 miles. It varied up and down as the river made cutoffs and created bars, but it always came back to the average. Ferguson lopped off 116 miles off the average in the 330 miles between the mouth of the Arkansas and the mouth of the Red River.

It was a mere fifteen land miles between the head of Rowdy Bend, the first Greenville bend, and the toe of Bachelor Bend, the last, but fifty miles by river. After 1880 the river added seven miles in the bends as it shaved sediment off the concave bends, deposited it on the head of the point bars, and threatened to chew away the levees on both banks. The Corps spent much time and money building revetments to stop the river’s meander at Rowdy Bend and Bachelor Bend. And, as Cramer noted, the river slowed and pooled in the bends at flood time, acting like a dam. Floodwaters back up to Arkansas City. In Ferguson’s view the bends had to go. Bachelor Bend, on which the City of Greenville is located, volunteered to go first. That was not Ferguson’s plan.[ii]

Bachelor Bend and Point Chicot aka Lake Ferguson north of Greenville

Ferguson only planned two cutoffs at the Greenville Bends and Bachelor Bend was not one of them. The bendway wrapped itself around Point Chicot. In 1882 the distance across the neck of the point was 5,500 feet, just over a mile. Within twenty years the distance had narrowed to 3,500. The Corps of Engineers constructed a protective dike, 6,250 feet long, across the axis of the neck. The Mississippi continued to scour the neck, reducing the distance across it to 2,600 feet by 1910. The Corps extended the dike a half mile. The Floods of 1922, 1927, and 1929 scoured a trench across the neck. The Corps responded with a mile-long permeable dike. The river broke through the new dike on July 8, 1933, deepened the trench, and forced Ferguson to move up his plans to take out the Greenville Bends by two years.

Spanish Moss Bend and Carter Point

While the river, in 1933, did not develop a new channel across Point Chicot, its elevation was three and a half feet higher on the upstream side of the point than the downstream side. The next flood could ream an uncontrolled cutoff through the point. That the river chose the place for the cut across Point Chicot and not the general added to his worries.  Therefore, to align the cut across Tarpley Neck to eliminate Spanish Moss Bend, and the cut across Ashbrook Point to eliminate Rowdy Bend with the river’s cut at Point Chicot, and to incorporate Miller Bend between the two artificial cuts, Ferguson had to redraw his plans.

Lake Ferguson Marina. Greenville’s Casino floats on Lake Ferguson, but goes no where.

Ferguson and his engineers finished the work the river had started across Point Chicot and aligned it properly in 1933, leaving Greenville on the shores of Lake Ferguson, old Bachelor Bend. When they finished the new channel, called the Leland Cutoff, carried fifty percent of the flow during the low-water season in 1933.

The Mississippi south of Greenville at the Leland Cutoff

The Corps started work on the lower end of Tarpley Cutoff in January 1935 directly opposite the head of the Leland Cutoff and completed it on Easter Sunday in April just as the crest of the 1935 flood streamed past Greenville. The cut, through sandy soil, was 13,000 long, 250 to 300 feet wide, and forty feet deep. Its slope was five times greater than the slope around Spanish Moss Bend. The new channel developed rapidly, but because the slope was steep and the soil sandy, the river flowed in a braided pattern and deposited many sandbars at the foot of Tarpley Cutoff.

The sinuosity of the old Greenville Bends allowed the Mississippi fifty-three miles to negotiate the steep grade between the top of Askbrook Cutoff and the foot of Leland Cutoff. The meandering channel gave the river a place to deposit its sediment: on Ashbrook Point, Point Comfort, Carter Point, and Point Chicot. Ferguson made his cutoffs and created a relatively straight, wide channel, but the steep grade remained and caused all kinds of problems for the engineers.

Tarpley Cutoff above Greenville

Almost as soon as it opened up, a sand bar formed at the mouth of the Tarpley Cutoff. The Corps dredged it away with a pump dredge only to have it form again two years later. Year in and year out the Corps dredged from the top of Ashbrook Cutoff to the foot of Leland Cutoff, but could not create a reliable navigation channel. The steep grade and the clay bed never allowed the river to adjust its slope or scour a deep channel. Nor could the river manage its sediment load through the wide channel that had a constant slope of a half-foot per mile.

Beginning in 1963 the Corps laid revetments on the banks to discourage scour and built training dikes to catch sediment and lock in the channel, reducing the need for so much dredging. But, still the river deposited sediment in the navigation channel, which shifted constantly, leading one potamologist to suggest the solution to the Greenville Bends was to use the training structures to create a sinuous channel that would allow the river to meander and handle its sediment the old way, by shaving it off the concave bends and depositing it on the convex bends.[iii]

Thus during the drought of 2012, when the river ran very low, barges ran aground and traffic backed up on the Lower Mississippi south of the Leland Cutoff at Greenville, Mississippi.


[i]             Cramer, 200.

[ii]             Winkley, Brian R., Man-made Cutoffs on the Lower Mississippi River, Conception, Construction, and River Response, Potamology Investigations, Report 300-2, Vicksburg: U.S. Army Corps of Engineers, 1977, 3-10; Camillo and Pearcy, Chapter 11, Chapter 12, http://www.mvd.usace.army.mil/mrc/Upon_There_Shoulders/Chapter11.htm.

[iii]             Winkley, Brien R., Man-made Cutoffs on the Lower Mississippi River, Conception, Construction, and River Response, Potamology Investigations, Report 300-2, Vicksburg: U.S. Army Corps of Engineers, 1977, 50-69; Schumm, Stanley, and Brinkley, Brien T., “The Variability of Large Alluvial Rivers, New York: American Society of Civil Engineers, 1994, 66-70; Smith, Lawson M., and Winkley, Brien R., “The Response of the Lower Mississippi River to River Engineering,” Engineering Geology, 1996, 441-442.