Hurricane Ida was so powerful it reversed the flow of the Mississippi River [View all]

As Hurricane Ida roared ashore in Louisiana on Sunday, the storm's force was so strong it temporarily reversed the flow of the Mississippi River.

Ida's winds snapped trees and tore roofs off buildings as its floodwaters blocked roads and submerged cars. The Category 4 storm was expected to dump up to 2 feet of rain in some areas and bring up to 7 feet of storm surge. More than 1 million people in Louisiana were without power.

A U.S. Geological Survey gauge at Belle Chasse, south of New Orleans, detected the Mississippi's flow moving backward around midday Sunday because of the volume of water Ida whipped up.

U.S. Army Corps of Engineers spokesman Ricky Boyette confirmed engineers detected a “negative flow” on the Mississippi River as a result of storm surge.

https://www.usatoday.com/story/news/nation/2021/08/30/mississippi-river-flowed-backward-due-strength-hurricane-ida/5647017001/
____________________________________________
I don't recall Katrina doing this, but I could be wrong.