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Lake Peigneur (locally pronounced [pæ̃j̃æ̹ɾ])^{[citation needed]} is a brackish lake in the U.S. state of Louisiana, 1.2 miles (1.9 kilometers) north of Delcambre and 9.1 mi (14.6 km) west of New Iberia, near the northernmost tip of Vermilion Bay. With a maximum depth of 200 feet (60 meters), it is the deepest lake in Louisiana. Its name comes from the French word "peigneur", meaning "one who combs."

Lake Peigneur
Lake Peigneur Show map of Louisiana Lake Peigneur Show map of the United States
Location	Iberia Parish, Louisiana
Coordinates	29.981°N 91.983°W / 29.981; -91.983
Primary inflows	estimated 8.47 cu ft/s (0.240 m3/s) from catchment[1]
Primary outflows	Delcambre Canal
Catchment area	10.2 sq mi (26 km2) of the Vermilion-Teche Basin[1]
Basin countries	United States
Surface area	1,125 acres (455 ha)[1]
Average depth	3 ft (1 m)[1]
Max. depth	200 ft (61 m)[1]

It was a 10-foot-deep (3 m) freshwater body, popular with sportsmen, until an unusual man-made disaster on November 20, 1980 changed its structure and the surrounding land.[1][2]

Drilling disaster

On Thursday, November 20, 1980, an oil rig contracted by Texaco was doing exploratory drilling in the lake, above the Diamond Crystal Salt Company salt mine that had operated for decades.[3] The drilling likely started a chain of events that turned the shallow lake from fresh to brackish water, with a deep hole.[4]

The evidence that could be used to identify the exact cause was destroyed or washed away in the ensuing maelstrom. However, the rig's 14-inch (36 cm) drill bit had become stuck just two-and-a-half hours before the draining was first observed.[5] After the fact, engineers from Texaco and Diamond Crystal worked together to pinpoint the likely location of the hole which may have pierced the mine. They placed it within a mined out portion of the 1300-foot level of the mine.[6] If the drill actually did puncture the roof of the mine, this would mean that Texaco had made a serious mistake about the location of the bore hole in relation to the mine. Whatever the precise cause, an opening formed in the bottom of the lake. The lake then drained into the hole, expanding the size of that hole as the soil and salt were washed into the mine by the rushing water, filling the enormous caverns that had been left by the removal of salt since 1919.

The resultant sinkhole swallowed the drilling platform, eleven barges holding supplies for the drilling operation, a tugboat, many trees, and 65 acres (26 hectares) of the surrounding terrain. So much water drained into the caverns that the flow of the Delcambre Canal that usually empties the lake into Vermilion Bay was reversed, causing salt water from the Gulf of Mexico to flow into what was now a dry lakebed. This backflow created for a few days the tallest waterfall ever in the state of Louisiana, at 164 ft (50 m), as the lake refilled with salty water from the Delcambre Canal and Vermilion Bay.[7] Air displaced by water flowing into the mine caverns erupted through the mineshafts as compressed air and then later as 400-foot (120 m) geysers.[7]

Although there were no human deaths, three dogs were reported killed. All 55 employees in the mine at the time of the accident escaped, with six employees later given awards by Diamond Crystal for heroism. Their successful evacuation was thanks to the mine's electrician who noticed a torrent of water and sounded the alarm, as well as the employees' discipline and training making their escape via the only elevator in an orderly fashion.[8][9] The crew of 7 on the drilling rig fled the platform shortly before it collapsed into the new depths of the lake. A fisherman who was on the lake at the time piloted his small boat to shore and escaped. Days after the disaster, once the water pressure equalized, nine of the eleven sunken barges popped out of the whirlpool and refloated on the lake's surface.[7]

Aftermath

Texaco and the drilling contractor Wilson Brothers paid $32 million to Diamond Crystal and $12.8 million to a nearby botanical garden and plant nursery, Live Oak Gardens, in out-of-court settlements to compensate for the damage caused.[10] The Mine Safety and Health Administration released a report on the disaster in August 1981 which exhaustively documented the event but stopped short of identifying an official reason for the disaster.[5] The mine was finally closed in December 1986.

Since 1994, AGL Resources has used Lake Peigneur's underlying salt dome as a storage and hub facility for pressurized natural gas.[11][12] There was concern from local residents in 2009 over the safety of storing the gas under the lake and nearby drilling operations.[13]

Salinity

This section does not cite any sources. (November 2020)

The lake had salty water after the event, not as a result of salt from the mine dissolving into the water, but from the inflow of salty water from the Delcambre Canal and Vermilion Bay, which are naturally salty or brackish. The event permanently affected the ecosystem of the lake by changing the lake from freshwater to saltwater and increasing the depth of part of the lake.

See also

• Bayou Corne sinkhole
• Döda fallet
• Lake Beloye (Nizhny Novgorod Oblast)
• List of sinkholes of the United States
• Rylands v Fletcher

References

External links

• Lake Peigneur: The biggest sinkhole ever created (archived)
• Oil Driller Breaches Salt Mine Under Louisana Lake on YouTube
• Endangered Earth - Sinkholes Assorted
• Warren, John K. (2006). Evaporites: Sediments, Resources, and Hydrocarbons. Berlin; New York: Springer Publishing. pp. 928–930. ISBN 9783540260110. Retrieved 2020-02-04. Contains a description of the event, with a focus on the geology of the region.
• Mine-mouth geyser problem, Chemical Engineering Education, an in-depth discussion of how the inrush of water could have created a powerful geyser
• Gold, Michael (November 1981). "Who Pulled the Plug on Lake Peigneur?". Science 81. pp. 56–63.
• The podcast Eclipsed has a two-part episode about Lake Peigneur. Part 1 Part 2

На других языках

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[de] Lake Peigneur

Der Lake Peigneur ist ein See im US-Bundesstaat Louisiana. Er befindet sich etwa zwei Kilometer nördlich der Stadt Delcambre und 15 km südlich von Lafayette.

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- [en] Lake Peigneur

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[fr] Lac Peigneur

Le lac Peigneur (Peigneur Lake) est un petit plan d'eau situé en dans la paroisse de l'Ibérie en Louisiane, aux États-Unis. Il est particulièrement connu pour la catastrophe industrielle qui l'a frappé le 20 novembre 1980.

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[it] Lago Peigneur

Il lago Peigneur (pronunciato [pæ̃j̃æ̹ɾ]) è un lago salmastro situato nello stato della Louisiana, 1,9 km a nord di Delcambre e 14,6 km a ovest di New Iberia, vicino all'estremità più settentrionale della baia di Vermilion. Con una profondità massima di 61 m, è il lago più profondo della Louisiana.

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[ru] Пенёр

Пенёр (фр. Peigneur) — солёное озеро в штате Луизиана, неподалёку от города Нью-Айбирия[en]. До 21 ноября 1980 года озеро Пенёр было пресноводным, занимало площадь около 5 квадратных километров и имело среднюю глубину 3,3 метра.

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