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Review "The Storm Hits" (pgs. 144-145) and "Disappearing Defenses" (pg. 147). Summarize the effects the levees had on the city of New Orleans.
The levees were meant to prevent flooding, but they caused sediment to build up in the lake and river, raised the water levels, and caused the city to sink. They also prevented sediment from being deposited in the marshes and on the barrier islands, causing them to wear away. As a result of all of this, the effect was terrible flooding.