No one can deny the severity of the 2011 fl ood, but some have argued the Great Flood of 1927 that devastated the lower Mississippi Valley was a much larger fl ood than the 2011 event; that the stages and discharges would have been greater in 1927 than actually measured had the federal levee not sustained seventeen major crevasses and allowed the fl oodwater to spread out. That may or may not be true. On the other hand, it can also be argued that stages and discharges in 2011 would have been greater than occurred had it not been for the three fl oodways placed into operation and the many dozens of post-1927 reservoirs constructed in the Missouri, Ohio and Arkansas/White basins that impounded mas-sive amounts of water during the winter and early spring, as well as for the major dredging program executed in the 1930s and 1940s that dras-tically shortened the river and increased the fl ood carrying capacity of the channel. As a result, the only way to provide a relative comparison of the two benchmark fl oods from the standpoint of hydraulics with the different protection systems employed would be to approximate fl ows and stages of the 1927 fl ood under 2011 project conditions or vice versa.
In either case, this is a diffi cult task to accomplish. It is fairly simple, though, to compare the performance of the fl ood control systems in place during the two precedent-setting fl oods.
For nearly fi ve decades prior to 1927, the Mississippi River Com-mission completed and then improved the general levee system begun by the states in the mid-nineteenth century. The commission coordi-nated local efforts, set standards and specifi cations for levee construc-tion, and allotted funds to cash-strapped levee districts throughout the lower valley. The commission believed the levees not only provided adequate protection from fl ooding, but would also promote scouring of the riverbed and provide a deeper navigation channel. For this reason, the commission rejected alternative methods of fl ood control, such as diversions, fl oodways, spillways, cutoffs and reservoirs. Critics derided
the commission’s approach as the “levees only” policy. As one fl ood after another overpowered the levee system, the commission responded by building the levees higher. The policy eventually left the lower Mis-sissippi Valley shattered after the Great Flood of 1927, as the massive fl ood completely overwhelmed the outmatched levee system. Crevasses caused by the deluge numbered between 120 and 225, with seventeen of those being major crevasses on federal levees. The remainder of the breaks – ranging in size from half a mile wide to a mere trickle – occurred in state or local levees. The unshackled fl oodwaters inundated 16.8 million acres in 170 counties in seven states – a swath roughly 50 to 150 miles wide running from Cairo to Baton Rouge on the east bank and Cape Girardeau to the coast on the west bank. The vast majority of the properties in the fl ooded regions were a total loss. Those buildings that remained standing quickly rotted from exposure. Estimates are that nearly one million people lived in the region, only slightly less than one percent of the total U.S. population at the time. This means one of roughly every 100 to 120 persons in the country lived through or was impacted by the fl ood.6
Statistics demonstrate the far-reaching impact of the 1927 fl ood.
Estimates of the death count range from 150 to 500. Some sources suggest a total number as high as 1,000 including indirect deaths such as from starvation. Many more were left homeless. Roughly 162,000 homes were unlivable, and 41,000 buildings were destroyed. The fl ood turned approximately 700,000 people into refugees; about 600,000 received aid from the Red Cross or other organizations. Seventy coun-ties from seven states received some fl ood damage; nineteen of them were more than 70 percent inundated. The fl ood destroyed some two million acres of farmland valued at $102.5 million. At maximum market value, the amount of land not used or ruined reached nearly $2 million.
This does not include the value of the more than 1.2 million poultry and 271,000 livestock that died in the fl ood, including 26,000 cattle and
population that formed a large part of Cajun income. It took years to restore these populations. In addition, damages to public infrastructure – roads, telephone poles, bridges and railroads – totaled $10 million.
Estimates of the total value of losses reached up to $1 billion, during an era when the federal budget rarely exceeded $3 billion.7
Equally disconcerting for the average citizen were the dramatic changes to the landscape imposed by the fl ood, which lingered long after it receded. When waters poured through crevasses, they left behind grooves and channels. In several locations, blue holes – large lakes of clear water a hundred feet deep – remained where fl oodwaters dug out holes when dumping through the levees. Such lakes now mark the spot of crevasses all along the river. Many landmarks had changed or disappeared beneath the silt left behind by the waters. Sandbars four and fi ve feet high grew up many miles from a crevasse. Silt and sand covered roads, fi rst fl oors of buildings, and acres of farmland, which required digging out to reach the fertile valley soil. It took several years for many farms to return to pre-fl ood profi tability. Public facilities, if not buried, were eroded or destroyed. Bridges washed out, roadways were full of holes and gaps, and railroads twisted, appearing as picket fences.
Debris – driftwood and destroyed homes – piled up in many locations, and most buildings had water marks on them. Large gaps existed in the levees, which in some cases had eroded until little more than small bumps remained. Even after fl oodwaters receded, lands normally prone to fl ooding remained underwater. Ditches turned to creeks, and creeks to wide rivers. Much of the Atchafalaya Basin returned to swampland.
The impression it left in the minds of its victims lingered for decades.8 Following the Great Flood of 1927, the nation galvanized its sup-port to prevent another similar tragedy from happening again. Congress authorized the Jadwin plan and then modifi ed it dozens of times to pro-duce the comprehensive MR&T project. Unlike the levees-only system during the 1927 fl ood, the comprehensive MR&T system functioned as designed during the 2011 fl ood. Not a single life was lost as a result of
Comparison of overflowed areas during the 1927 and 2011 floods.
the fl ood. Water lapped at the top of fl oodwalls and levees the length of the river, exerting unprecedented levels of pressure on the backbone of the protection system, but the levees withstood the record stages and pressure due in large part to the operation of three fl oodways and the storage capacity provided by non-MR&T reservoirs in the Ohio and Arkansas-White basins. Flood fi ght teams, composed of federal, state, and local resources that battled unusually frigid temperatures, high winds, and stinging rain, also assisted the levees in holding back the onslaught of the river. With the levee system not experiencing any crevasses, only 6.3 million acres fl ooded within the 22.4-million acre project footprint. In other words, sixty-two percent of the property inun-dated during the 1927 fl ood escaped overfl ow in 2011. Nearly all of the land that fl ooded during the 2011 fl ood was located between the levees or other unprotected areas, or within the designated fl oodways and backwater areas. Approximately 950,000 households, along with major industrial, commercial, and retail facilities that stood in harm’s way escaped the fl ood undamaged. Most of the estimated 35,000 households damaged by the fl ood were located in unprotected areas or within the designated fl oodways. MR&T project features also prevented $7.3 bil-lion in crop losses. All told, the MR&T project prevented $110.6 bilbil-lion in damages, not including potential losses from interrupted business activities and related impacts.9
The pages that follow endeavor to provide a transparent depiction of the 2011 fl ood within the MR&T footprint and, in the process, give evidence to the realities just described, while providing necessary his-torical context for greater understanding of key features of the project.
It is the story of prudent foresight, heroic actions, agonizing decisions, and extreme personal sacrifi ce.