Flooding on the Mississippi River is approaching New Orleans, leaving officials with a dilemma on how to handle it. In about 72 hours, floodwaters will hit the Old River Control Structure — essentially a canal linking the Mississippi River with the Atchafalaya River. This structure controls how much water goes into the two rivers; under normal conditions, the Lower Mississippi gets 70 percent of the flow and the Atchafalaya gets the remainder. The U.S. Army Corps of Engineers is currently debating doubling the flow of water into the Atchafalaya and opening the Morganza Floodway downstream, which — in theory — would remove the flooding threat downstream on the Lower Mississippi, including New Orleans, at the cost of flooding the Atchafalaya Basin, a lightly populated area with only a few thousand acres of cropland. The graphic above shows the worst-case flooding scenario estimated by the Army Corps of engineers if the Morganza Floodway is not opened.
