Flood of 2011 - Frequently Asked Questions and Answers (Update 5-16)

Since there are so many new people coming here for a resource, I thought we should post some FAQ's to avoid mass threads on the same topics. I will update as much as possible.

1) Q - Are BR and NO still in danger?
A - To some degree, yes. The Mississippi River will still be at historically high levels for weeks. But the opening of Morganza and Bonnet Carre have reduced (if not ended) the risk of overtopping. The system is still in some danger of a breech. They will be looking for sand boils (spots where the pressure from the water force dirt on the dry side of the levee to start bubbling) and other weak spots constantly. Be cautious but don't let your guard down. We aren't completely out of the woods yet.

2) Q - Will _______(insert road) be closed when I travel?
For Louisiana, visit the LADOTD website for phone numbers and web alerts, and webcams LINK In Mississippi, you can visit LINK

3) Q - Why is BR and NO shown as cresting now instead of the end of the month?
A - The opening of the spillways will keep the water height and flow rate at close to the levels they are now. So this is sort of a manmande crest while the crest of water will come down around the 23rd/24th with everything in excess of 1.5 million CFS being sent through ORCS and Morganza.

4) Q - What is Morganza, ORCS, and Bonnet Carre?
A - You will be hearing these terms plenty so here is a great map online discuss the location and use of these structures: MAP LINK
Essentially, ORCS and Morganza will reduce River flow and height to Baton Rouge while Bonnet Carre does the same for New Orleans.

Here's another good link from The Dude LINK

5) Q - How soon will water from the Morganza opening get where I live?
A - Morganza opened on Saturday, May 14 at 3:00 PM. They are opening more bays each day. Here is the map projectioning how long the water will take to reach certain areas (although on 5/16 it was announced the water was moving slightly slower than expected): LINK

6) Q - What is flow rate?
A - The average flow rate on the River during a year is 450,000 CFS. This means that 450,000 cubic feet of water passes at a particular point at that given second. This rate can have serious effects on navigation (making it harder to steer and control River traffic) and probably causes erosion along the levees at high speeds. As stated above, the Corps has specific ceilings for flow rates past certain points. The ceiling in BR is 1.5 Million CFS (shown in many reports as 1500KCFS) and NO is 1.25 Million CFS. The last prediction for River flow in Vicksburg, MS at the crest was 2.72 Million CFS. According to the America's Wetlands site, the highest recorded flow on the River was 2,345,000 CFS in 1927. This means about 1.22 Million CFS will be diverted through ORCS and Morganza.

To put this in perspective, if the Corps diverts 1,220,000 CFS into the Atchafalaya Basin, they are essentially sending the average of the Mississippi River two and a half times that way....while 3 times that amount is going past Baton Rouge. Flow rate is also the reason you will see restrictions on River traffic (like current restrictions on night navigation between BR and NO). You don't want a tanker, tug with barges, or any large vessel loosing control and hitting the top of a levee.

A long read but good explanation and history is on this America's Wetland Resources page: LINK

7) Q - Why is this happening?
A - See the link above from America's Wetlands. 41% of the continental US drains through the Miss River. Just an abnormal amount of snow melt and rainfall in areas North of Louisiana.

There are a few more FAQ's a few posts below as we ran out of space here. Thanks. Good luck and God Bless! It's going to be a tense few weeks.