NOLA-ing: Bonnet Carré Spillway Opening

For only the eleventh time in history, the Army Corps of Engineers opened the Bonne Carré Spillway in St. Charles Parish on January 10, 2016. Once they open the 7000 foot spillway, running from Norco to Montz, it flows into a roughly 5.7 mile floodway, the purpose of which is to divert water from the Mississippi River into Lake Pontchartrain, which will then flow into the Gulf of Mexico. Fun fact: Lake Pontchartrain is not actually a lake. By definition, a lake is completely enclosed, but Lake Pontchartrain is open marsh on its eastern side, around what is known as the Rigolets, which turns into Lake Borgne, which turns pretty much into the Gulf of Mexico. Thus, instead of a lake, it is technically an estuary, meaning it is only partially enclosed and has access to open water. (When I taught Geography, this little tidbit always stumped and intrigued my students.) This is why the lake is brackish water and both salt and freshwater fish can be found and why, even though opening the Bonnet Carré Spillway and causing freshwater to flow into lake can disrupt wildlife in the lake, it will not completely decimate the ecosystem.

Completed in 1931, it was designed to divert some of the water from the Mississippi River, thereby lowing the river and reducing the threat of flooding within New Orleans and the surrounding cities. After the Great Mississippi River Flood of 1927, the government started work on the spillway and other levees that would help prevent future flooding.

There are 350 bays across the spillway with giant pins that cranes lift open when the water needs to be diverted. Usually, depending on the amount of water that needs to flow into the spillway to relieve pressure from the river, not all 350 bays are opened. Only five of the eleven times have the Army Corps of Engineers opened 100% of the bays.

On January 10, the spillway opened again at its record earliest, thanks to heavy December rainfall along the upper Mississippi River and its tributaries. Twenty of the 350 bays were opened, with more possibly to open after authorities assess the river’s height. Hundreds of people trekked to the levee to watch the spillway open, including Kurt and I. While we could not be there for the opening at 10am, we made it out there around 4:30pm. We first went to the Montz side of the spillway, where the pins were still in place. Though not much action, there was still a small crowd of people marveling at the sight of the high water.

After some pictures, we drove over to the Norco side of the spillway, where there was much more action. A larger crowd of people surrounded the steps around the spillway, in addition to people fishing along the edge, hoping to take advantage of any fish coming through. The force of the water was amazing and as I put my phone through the black metal bars to take better pictures, I was terrified that the force of the water would jump up and snatch it out of my hands.

The water spilling through the bays was intense. As we stood along the waters of the mighty Mississippi in the frigid air as the sun sank below the horizon, I realized why people, at least this one, are so fascinated with the opening of the spillway. Mother Nature is such a powerful force and usually, she gets the better of us. However, whatever the consequences, sometimes we can control her. And to see her pushing and groaning and trying in vain to fight against us and reclaim her ground, to witness the power and intensity but still feel relatively safe, we realize just how much of the world we think we have mastered, only to with one wrong move, Mother Nature could destroy it all. And that is a sight to behold.

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