Sauve's Crevasse

Sauvé's Crevasse was a Mississippi River levee failure in May 1849 that resulted in flooding much of New Orleans, Louisiana.

In May 1849 the Mississippi reached the highest water level in this area observed in twenty-one years. Some seventeen miles (27 km) up river from the city of New Orleans in Jefferson Parish lay a plantation belonging to Pierre Sauvé, in what is now River Ridge, Louisiana. There, on the afternoon of May 3, the levee gave way. At once it was seen impossible to stem the raging waters.

People in New Orleans hoped that the flood would find its way into Lake Pontchartrain by some channel or the other, before reaching the city. But the swamp rapidly filled; the water approached the outskirts of the town; and it was quickly too late to throw up any adequate defenses.

By May 15 the water was at Rampart Street. The First Municipality went to work on a small levee which lay along the lower bank of the Carondelet Canal, and raised it sufficiently to shut out the flood from that part of the city. Some of the water was drained via the canal into Bayou St. John and thence into Lake Pontchartrain. This protected much of the city below the Canal. This was a significant success, which kept the flooding out of the Faubourg St. John, Marigny, and other downriver portions of the city. By providing an outlet for the waters, the action prevented deeper and more widespread flooding above the Canal.

However, most of what is now Uptown New Orleans and the New Orleans Central Business District were badly flooded. The water spread from the low-lying "back of town" into the higher ground closer to the River, and attained its highest point on May 30. In the CBD, floodwater reached Bacchus (Baronne) Street from the upper limits of Lafayette to Canal. Where the ground was low, floodwaters extended into Carondelet. Further Uptown, between Louisiana and Napoleon avenues, the flooding stopped just short of Magazine Street. In Carrollton, above Canal Avenue (Carrollton Avenue), the waters reached to Forth Street (Oak), and below to Burthe.

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