As the surge from Tropical Storm Barry piles up Gulf of Mexico waters off the mouth of the river, forecasters say the river will have nowhere to drain, and unseasonably-high water will start to back up in the river channel.
This is a foot lower than the previous forecast. Like the previous forecast, the river level is expected to increase dramatically Saturday morning, peak around 1:00 p.m., then fall just as quickly.
The river levees in the New Orleans area average around 20' high in some downriver areas, and in some spots it dips even lower.
You can check out the height of the levee all along the hurricane and river flood-risk reduction system with this interactive tool on the U.S. Army Corps of Engineers web site: