How One Engineer's Tiny Mistake Made An Entire Louisiana Lake Completely Disappear

James Felton

James Felton

Senior Staff Writer

clockNov 16 2020, 16:31 UTC

Maxim Tarasyugin /

Lakes, if you live near one, are one of those things — like the Sun or James Corden on TV that you take for granted you'll see the next day whether you want to or not. However, that isn't always the case. In certain circumstances, they can just straight up disappear within a few hours right before your very eyes.

Lake Peigneur


Lake Peigneur was a small and shallow saltwater lake, just off Vermilion Bay in south Louisiana. One fateful November morning in 1980, it briefly became an ex-lake, before becoming the deepest lake in the whole of Louisiana.

On November 20, a crew of oil drillers contracted by Texaco headed out for a day of exploratory drilling on the lake, probably thinking about how normal their day was going or how accurate they were at picking locations to drill for oil. When they began drilling, they soon ran into a problem: Their drill appeared to be stuck. In retrospect, that was only a minor problem as they were about to see the whole lake disappear in front of their eyes, along with their rig, several boats, and a small island.

Under the lake was a salt mine that had been there for over 100 years. The drilling crew thought they were far from the mine, but when they attempted to remove their drill, the rig started to tilt shortly before disappearing, which pretty much confirmed there might have been a bit of an oopsy.


The crew were able to escape to the shore, where they watched the 46-meter (150-foot) rig disappear into what used to be a 3-meter (10-foot) deep lake, like a reverse ecological disaster version of when Mary Poppins produces a ladder from her handbag. Several barges near the hole disappeared into what was now a giant whirlpool, as the hole kept growing. Meanwhile, miners in the mine below began to evacuate as the shaft filled with water.

Thankfully, they too got out in time and were able to watch as part of a nearby island also slid into the hole with enough force to cause water to launch 122 meters (400 feet) into the air out of the mine's opening.

The lake used to feed into the Vermillion Bay through the Delcambre Canal, but this flow reversed once it was emptied and water from the bay was carried backward, temporarily creating a 50-meter (164-foot) waterfall, before filling the newly dug out hole with water, making it the largest lake in Louisiana.

Texaco paid $32 million in an out-of-court settlement with the Diamond Crystal Salt Company for damages to the mine and $12.8 million to Live Oak Gardens Foundation and Live Oak Gardens Ltd.
Like huge screw-ups? Try this one on for size.  

So, how did this accident occur? Well, like the time that NASA’s Mars Climate Orbiter burned up in Mars' atmosphere due to a failure to convert from pounds of thrust to newtons, it was an error of using the wrong system of measurement.

The engineer on the project believed the map he was using used a Mercator Projection coordinate system, whereas the map actually used a Universal Transverse Mercator coordinate system. 

Representing a 3D world on a 2D map is always going to end up with some issues and some compromises. No matter how accurate you try to make it, you will end up with stretched areas, squashed countries, or else parts of the map cut out altogether.


The map you are likely familiar with is one based on the Mercator projection, created by cartographer Gerardus Mercator in 1569. It's a cylindrical map projection, in which you place the globe into a cylinder and then project each point of the map onto a corresponding point on the cylinder. Meridians (imaginary vertical lines going through the Earth from the North to South pole) are mapped onto vertical lines equally spaced apart on the map, and circles of latitude (imaginary horizontal lines from East to West) are mapped onto equally spaced horizontal lines.

Both of the maps that caused the error are based on Mercator projections, but in the Universal Transverse Mercator coordinate system the world is split into 60 planes and uses more localized projections, resulting in more accurate maps on a local scale. Use the wrong one and you'll end up somewhere you shouldn't be, and that's how one engineer's mistake led a lake to disappear.