Man the Pumps!

How, exactly, do we keep a river and lake out of New Orleans’ infamous soupbowl? Ladies and gentlemen: meet the West Closure Complex.

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The French have long been admired for their determination to live well. Give them lemons, and they'll make an elegant little tart and pair it with a wine. This tendency explains a lot about the placement of New Orleans: if the mouth of the biggest river in your North American colonies is surrounded by a low-lying swamp, build a city there anyway! Fill it with art and food and wine and song! That's how a history-packed, fun-loving city comes to be built below sea level, alongside a river, next to a lake. New Orleans, its suburbs, and most of the rest of South Louisiana is so surrounded by water that, during flood events, there's simply not many places for more water to go.

That's where good old American engineering steps in to safeguard French joie de vivre. I had the chance to visit the Gulf Intracoastal Waterway West Closure Complex (WCC) in Belle Chasse, part of the Southeast Louisiana Flood Protection Authority – West, which protects parts of Orleans, Jefferson, and Plaquemines parishes. This juggernaut of flood control can move over 19,000 cubic feet of water per second—enough to fill an Olympic swimming pool in three seconds—boasts 4,200 linear feet of concrete T-walls, and is constructed to defend against a one-hundred-year storm event through at least 2057. I left my tour feeling reassured; there’s a whole lot more engineering (and cement) between us and a catastrophic flood than there used to be.

This 225-foot-wide span is usually open, but it can be sealed up tight in the event of a flood, making the Intracoastal Waterway the biggest “sealable” waterway in the world outside of the similarly flood-prone Netherlands, which has been engineering ways to live below sea level since the Middle Ages.

WCC was built after Katrina, when it became clear that the existing flood control administration and architecture were insufficient. Administratively, this resulted in the consolidation of local levee boards into a smaller number of bodies better able to coordinate the many aspects needed for effective regional flood control—the water doesn’t stop at parish lines, so neither can preparedness. Physically, the fix included the construction and improvement of levees and other flood control structures, among them the WCC. Construction of this $1.1 billion protector began in 2009; it wasn't fully completed until 2014, but by the time Isaac hit in 2012, it was operational enough to be activated and prove its functionality and worth.

[You might like: Crossing Water.]

The WCC is on the Jefferson/Plaquemines parish line, far enough out that I took the wrong dirt road and briefly got stuck in the mud. It sits astride the Intracoastal Waterway, just below the juncture of the Harvey and Algiers Canals. On either side of the closure complex, the waterways are lined with levees; Regional Director John Monzon describes their height in terms of years. They were built up “fifty years” in 2007, which translates to about sixteen feet and means that they will ideally not need to be built back up until 2057, when the gentle, inescapable sinking of South Louisiana's alluvial soils will have caused them to recede. The closure complex itself looks like a dam from the road, but isn’t—at least not usually. It can seal off the waterway within a handful of minutes if flooding looms; but under normal circumstances, the waterway is left open to allow commerce and marine life to use the waterway, as they always have. The waterways of Louisiana are vital arteries, despite their occasional danger, and the economy and ecology of the area would be badly damaged if they were impassable.

Monzon gave me the “nickel tour,” which was exactly what I wanted. He led me along a broad concrete walkway on the inland side of the structure and showed me a series of metal grates, partly below the waterline, that run down that side of the structure. This is where floodwaters coming from the inland, Jefferson Parish side can be sucked up into the pumps and let out on the downriver side; the grates keep debris from clogging or damaging the pumps. Under normal circumstances, the water speed at the grates won’t exceed two feet per second, slow enough to prevent most river animals from getting trapped. When miscellaneous debris collects on these grates, workers at the complex can activate machines, essentially giant metal rakes or combs, to descend and scoop the materials (plants, litter, and the odd dead fish) out of the grate. The combs dump the mess onto the side of the walkway we were on, where a small earthmover gathers it for disposal.

I was already impressed, but this was the tip of the iceberg. We rounded a corner, and I could now see the main gate. This 225-foot-wide span is usually open, but it can be sealed up tight in the event of a flood, making the Intracoastal Waterway the biggest “sealable” waterway in the world outside of the similarly flood-prone Netherlands, which has been engineering ways to live below sea level since the Middle Ages. When a flood threatens, two wedge-shaped units swing into the waterway to meet and make a seal, preventing storm surge from swelling the Harvey and Algiers canals and keeping water out of the heavily populated areas of the West Bank. The wedges are good solid steel, lined with rubber; buoy tanks within them are filled with air so they can swing, then filled with water to allow them to sink into a groove in the waterway’s bed. This process takes a mere seven minutes from “sound the alarm” to “well, that’s taken care of.” As a failsafe, there’s also a cable draw system if any aspect of the gate closure fails.

[You might enjoy: Forts of Plaquemines Parish.]

As we went into the interior of the complex to see the pumps, Monzon explained that the eleven diesel engines that ran them drew from six fifty-thousand-gallon fuel tanks—enough for four to seven days of operation during a storm.

“See those things that look like mufflers?” Monzon asked me, pointing to some metal structures on the downriver side of the complex.

            “Yeah.”

            “Those are mufflers. The engines that drive these pumps can get really loud.”

The pumps here are called “flowerpot pumps,” and use a system in which a whirling blade essentially whips the excess water up the shaft to the exit point. This is not the most efficient way to move water, but it is essentially failsafe; some other pump stations use siphon-based systems, which can be overwhelmed in a serious event and are more likely to be affected by stray debris.

The big interior of the complex looks both basic and futuristic: there’s bare concrete and shining machinery everywhere, but everything is run by touchscreen. The ceiling is four stories high to accommodate the crane that stays in the structure—(a machine, not the long-legged waterbird). As Monzon explained, the various machines must have parts inspected, repaired, and replaced, and having a crane inside makes more sense and is more efficient than trying to get a crane inside when one is needed.

Monzon explained that many people in the area are seeing lower flood insurance rates, in part because of the West Closure Complex and other flood control infrastructure. These savings haven't always been paid forward; ballot initiatives to fund the maintenance of these structures, which of course everyone wants and no one wants to pay for, have a low pass rate in the affected parishes, raising uncertainty about where money for upkeep will come from.

The tour looped around perfectly, and I was back at the car. I noticed a little cluster of houses, not far back from the road and so not very far from the river at all. They were just upstream of the closure complex. I hoped that was far enough.

Details.

The West Closure Complex hosts occasional tours and open houses; the best way to keep track of these and to stay up-to-date on other news is to visit the Southeast Louisiana Flood Protection Authority – West. slfpaw.org.