"Katrina" and the damage it produced was caused by a HER-A-CANE. It was a very big, round storm that came in from the Gulf of Mexico to Louisiana and Mississippi (after Florida).
At one time, Katrina had wind gusts above 160 mph and piled water more than 25 ft. above sea level.
The damage was not caused by pipeline construction or any of the other items in your story. The damage was caused by the very big HER-A-CANE. Here is a book that I think would be fun and educational for you and your buddies to read. Then, perhaps, you will write a story that is correct next time.
Your friend, Michael