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A 300-Year Struggle

Storm That Drowned a City homepage

A French Foothold Louisiana Levees-Only Policy Spillways & Sprawl Hurricane Season Modern Times

The French explorer Jean-Baptiste Le Moyne, Sieur de Bienville made a fateful decision in 1717 when he chose the site for New Orleans along a sharp bend in the Mississippi River. Bienville selected the site against the objections of his chief engineer, who realized that the area suffered from periodic floods. New Orleanians have been paying the price of Bienville's insistence ever since, from the first major flood shortly after the town's founding to the merciless juggernaut that was Hurricane Katrina. Here, follow the historical trajectory of New Orleans' ever-worsening struggle to keep out water.—Peter Tyson


A French foothold

A Frenchman visiting the Mississippi River near what would become New Orleans writes, "This last summer I examined better than I had yet done all the lands in the vicinity of this river. I did not find any at all that are not flooded in the spring. I do not see how settlers can be placed on this river."

The French establish "Nouvelle-Orleans" on the site of an erstwhile Quinnipissas Indian village. (Indians first occupied sites in eastern New Orleans around 500 B.C.) Like the Quinnipissas, the French select the site because it's the highest and driest spot for several miles around. Within a few years slaves are put to work clearing land on the natural levee the French have selected for the town.

Surveyors lay down a grid pattern of streets of some 40 blocks, with drainage ditches around each block and a dirt palisade surrounding the town. A never-ending battle against high water—both floodwaters and high water tables—has begun.

Construction starts on a four-foot-high earthen levee (from the French word lever, "to raise"), the beginning of three centuries of combating high water through embankments. By 1726, the levee remains incomplete, though a section fully 18 feet tall stands before the Place d'Armes (now Jackson Square) in the heart of the nascent town.

After New Orleans floods in 1731, the town's Superior Council mandates that all settlers along the river nearby build levees. By 1732, earth-and-timber embankments reach from 12 miles south of New Orleans to 30 miles north on both sides of the Mississippi.

Floods in the town remain troublesome throughout the 1740s, as city engineers build their levees ever higher to cope with increased flood levels brought on by changes in the landscape upriver. By 1752, landowners have added another 10 miles of levees beyond their 1732 extent.

1875 copy of 1798 map

In this 1875 copy of a 1798 map of New Orleans, one can roughly gauge the width of levees the French built along Bayou Metarie (center left) and Bayou Gentilly (upper right) by the extent of land on either side of the bayous that is not marked by tree symbols.

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Into American hands

With the Louisiana Purchase, President Thomas Jefferson acquires New Orleans and an additional 828,000 square miles of land in the south-central U.S. from Napoleon Bonaparte. The purchase price: $15 million.

The first steamship arrives in New Orleans. The town begins to grow as an important trading center, serving as a critical link between the world's oceans and 19,000 miles of river along 31 U.S. states and two Canadian provinces.

After a nearly month-long flood this year drives many poorer New Orleanians from their homes, Edward Fenner, a noted New Orleans medical authority, writes, "should not those in affluent circumstances come to the aid of their less fortunate fellow citizens, great indeed, we fear, will be the distress of the latter, from poverty, famine, and perhaps pestilence."

Another flood in New Orleans produces the highest water recorded up to the time. The deluge sparks a renewed bulwark-building campaign. Laws are now in place both regulating the dimensions and maintenance of levees and mandating a tax to pay for their construction.

Louisiana State engineer P. O. Hebert warns that New Orleans is in "imminent danger of indundation" annually: "Every day, levees are extended higher and higher up the river—natural outlets closed—and every day the danger to the city of New Orleans and to all the lower country is increased. Who can calculate the loss by an overflow to the city of New Orleans alone?"

Two topographic engineers describe the flood of 1849 as the most destructive flood known. A breach in the levee on the east bank of the Mississippi 18 miles above New Orleans does an "immense amount of damage," they write, inundating the city for 48 days. Another flood the following year convinces the federal government to grant monies to build a continuous levee system.

LA purchase treaty

The Louisiana Purchase Treaty secured the present-day states of Louisiana, Arkansas, Oklahoma, Missouri, Iowa, Nebraska, and North and South Dakota.

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The levees-only policy

By mid-century, city engineers agree that the best way to control the Mississippi is to force it to flow down a single channel with large levees on either side. The river will of necessity scour out a deeper channel for itself, reducing the flood threat, they believe. This becomes policy until 1927, when a disastrous flood in New Orleans proves the folly of the policy.

Four times between 1849 and 1874, a breach occurs in the Mississippi River levee at Bonnet Carré north of New Orleans, each time sending a flood towards the city at an estimated rate of 150,000 cubic feet per second. One commentator writes that floodwaters swept away "dwellings, sugar-houses, crops, and fences, like chaff before the wind," and even threatened the safety of the city itself.

The worst flood in the Mississippi River up until this time opens more than 200 breaches in the river's levees, most of them in Louisiana, and keeps New Orleans at flood stage for 91 days. One writer says this flood "left the people of the valley prostrate."

In Life on the Mississippi, published this year, Mark Twain scoffs at the Mississippi River Commission's flood-control mission, writing that "One who knows the Mississippi will promptly aver ... that ten thousand River Commissions ... cannot tame that lawless stream ... cannot bar its path with an obstruction which it will not tear down, dance over, and laugh at."

A day-long assault of 30-foot waves overtops coastal levees and destroys a fishing village south of New Orleans, killing 1,500 people.

New Orleans is now the 14th-largest U.S. city, with a population approaching 400,000. Improvements in drainage technology, foremost among them a new screw pump invented by engineer Albert Baldwin Wood, enable the city to start expanding northward toward Lake Pontchartrain in the 1920s.

The Army Corps of Engineers finishes connecting New Orleans to the Gulf Intracoastal Waterway, a 1,300-mile canal stretching from Texas to Florida. During Hurricane Katrina in 2005, this waterway will unfortunately provide a direct route for storm surge into eastern New Orleans.

On April 29, with dangerously rising floodwaters in the Mississippi threatening to overwhelm New Orleans, Louisiana's governor orders the Army Corps of Engineers to dynamite a levee along St. Bernard Parish, allowing floodwaters to drain across the parish's rural neighborhoods and wetlands to Lake Borgne and the Gulf of Mexico. New Orleans proper is saved, but the parish is devastated. More than 200 people die and 700,000 are left homeless. The disaster marks the end of the levees-only policy; as one writer puts it, "a policy had been breached and the pouring waters were sweeping an era away."

Levee, 1900

Workers strengthen a levee in the Third District, 1900.

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Spillways and sprawl

Congress acts swiftly to address the flood-control problem, passing the 1928 Flood Control Act. Ostensibly the act says that the Mississippi cannot be managed by levees alone, but also requires spillways and reservoirs. The act authorizes the building of a spillway at Bonnet Carré near Lake Pontchartrain to shunt floodwaters away from New Orleans and into undeveloped areas.

The wetlands between New Orleans and Lake Pontchartrain, which provide habitat for wildlife, trapping and other livelihoods for residents, and, perhaps most importantly, hurricane protection, continue to disappear as the government drains them and people build homes there. Marsh loss in southern Louisiana will reach 35 square miles a year or more over the coming decades, a rate that by the time Katrina hits in 2005 will have a severe impact.

The 7,000-foot-long Bonnet Carré spillway is finally completed. It includes 350 openings, each bearing 20 timber planks that can be individually removed to increase flow out of the spillway. Within a year it earns its keep, protecting New Orleans from the flood of 1937 by sending floodwaters across a narrow strip of land into Lake Pontchartrain. The spillway will successfully do the same seven more times over the next 60 years.

Corps engineers complete the Mississippi River-Gulf Outlet, a 76-mile canal that offers a direct route for ships between New Orleans and the Gulf of Mexico, saving valuable time over traveling up and down the sinuous Mississippi. But like the Gulf Intracoastal Waterway, the canal also serves as a highway to New Orleans for hurricanes and their storm surges.


During a flood, workers can remove individual timbers and place them atop the Bonnet Carré Spillway, allowing for very precise release of floodwaters.


Hurricane season

Hurricane Betsy sideswipes New Orleans, killing several dozen and becoming the first storm to cause more than $1 billion in damage. Four parishes sustain significant flooding. "God, it was like one giant swimming pool as far as the eye could see," one resident of Chalmette recalled. "A woman who lives down the block floated past me, with her two children beside her."

From 1559 to 1969, 160 recorded hurricanes struck Louisiana, an average of one hurricane every two and a half years. With the state's and New Orleans' vulnerability to hurricanes in mind, as exemplified by Betsy, the Army Corps of Engineers in the 1960s develops its first hurricane-protection plan for the city and state.

In April, the worst flood since 1927 hits the city. More than two dozen people die, and damage is estimated at $427 million. But the levees hold, preventing a much greater catastrophe. For the first time in history, a major flood has been diverted successfully to the sea.

In response to Hurricane Betsy 20 years earlier, city engineers finally approve hurricane-protection projects along the New Orleans lakefront and in St. Bernard Parish. The projects include strengthened seawalls and levees along the lakefront as well as within the Industrial Canal and along the Mississippi River-Gulf Outlet. The projects are 80 percent complete by 1994.


Hurricane Betsy flooded 164,000 homes when she swept through the New Orleans area in September 1965.

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Modern times

New Orleans becomes America's number-one seaport in total tonnage handled.

Twenty inches of rain fall in a single day, causing seven deaths and $1 billion in damage across three parishes. With an average rainfall of 58 inches, New Orleans is one of the rainiest cities in the U.S. And with the city having expanded into numerous low-lying areas, it has become extremely vulnerable to floods not just from the river and hurricanes but from its own protracted rainy season.

Improved protection along the London Avenue, Orleans Avenue, and 17th Street Canals in Orleans Parish is 90 percent complete. The improvements include lining the three canals with "I" walls and building 10 flood-proof bridges where roads cross the canals. New Orleans, it is thought, is now well prepared to withstand a Category 3 storm.

Hurricane Katrina, a Category 4 storm when it makes landfall on August 29, precipitates the greatest natural disaster in U.S. history, killing more than 1,000 people, leaving 100,000 homeless, and causing damage in the hundreds of billions of dollars. Most of New Orleans is underwater as overtoppings and breaches occur in the 17th Street, London, and Industrial canals as well as along the Gulf Intracoastal Waterway and Mississippi River-Gulf Outlet. (For more details, see How New Orleans Flooded.)

Flooded New Orleans

In the wake of Hurricane Katrina, New Orleans' Superdome served for countless displaced residents as an island in a sea of inundation.

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Further Reading
Transforming New Orleans and Its Environs: Centuries of Change
Craig E. Colten, editor. University of Pittsburgh Press, 2000

Land's End: A History of the New Orleans District, U.S. Army Corps of Engineers, and Its Lifelong Battle With the Lower Mississippi and Other Rivers Wending Their Way to the Sea
by Albert E. Cowdrey. U.S. Army Corps of Engineers New Orleans District, 1977


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