Lake Peigneur

Lake Peigneur
Location	Iberia Parish, Louisiana, USA
Coordinates	29.9808°N 91.9833°W / 29.9808; -91.9833{{#coordinates:29.9808|N|91.9833|W|type:waterbody_region:US			primary	name= }}
Primary inflows	estimated 8.47 cubic feet (0.240 m3) per second from catchment
Primary outflows	unknown to Delcambre Canal
Catchment area	10.2 square miles (26 km2) of the Vermilion-Teche Basin
Basin countries	United States
Surface area	1,125 acres (5 km2)
Average depth	3 feet (1 m)
Max. depth	200 feet (61 m)

The backwards flow of the normally outflowing Delcambre Canal temporarily created the biggest waterfall in Louisiana

Lake Peigneur is located in the U.S. State of Louisiana 1.2 miles (1.9 km) north of Delcambre and 9.1 miles (14.6 km) west of New Iberia, near the northernmost tip of Vermilion Bay.

History

The lake was a 10-foot (3 m) deep freshwater lake popular with sportsmen until an unusual man-made disaster on November 20, 1980, changed the structure of the lake and surrounding land.

Disaster

On 20 November, 1980, when the disaster took place, the Diamond Crystal Salt Company operated the Jefferson Island salt mine under the lake, while a Texaco oil rig drilled down from the surface of the lake searching for petroleum. Due to a miscalculation, the 14-inch (36 cm) drill bit entered the mine, starting a chain of events which turned what was at the time an almost 10-foot (3.0 m) deep freshwater lake into a salt water lake with a deep hole.

It is difficult to determine exactly what occurred, as all of the evidence was destroyed or washed away in the ensuing maelstrom. One explanation is that a miscalculation by Texaco regarding their location resulted in the drill puncturing the roof of the third level of the mine. This created an opening 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 left by the removal of salt over the years. The resultant whirlpool sucked in the drilling platform, eleven barges, many trees and 65 acres (260,000 m²) of the surrounding terrain. So much water drained into those caverns that the flow of the Delcambre Canal that usually empties the lake into Vermilion Bay was reversed, making the canal a temporary inlet. This backflow created, for a few days, the tallest waterfall ever in the state of Louisiana, at 164 feet (50 m), as the lake refilled with salt water from the Delcambre Canal and Vermilion Bay. The water downflowing into the mine caverns displaced air which erupted as compressed air and then later as 400-foot (120 m) geysers up through the mineshafts.

There were no injuries and no human lives lost. All 55 employees in the mine at the time of the accident were able to escape thanks to well-planned and rehearsed evacuation drills, while the staff of the drilling rig fled the platform before it was sucked down into the new depths of the lake, and Leonce Viator, Jr. (a local fisherman) was able to drive his small boat to the shore and get out. Three dogs were reported killed, however. 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.

Salinity

The lake had salt water after the event, not as a result of water entering the salt mine, but from the salt water from the Delcambre Canal and Vermilion Bay, which are naturally salt or brackish water. 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.

Aftermath

The drilling company, Texaco and Wilson Brothers, paid $32 million to Diamond Crystal and $12.8 million to nearby Live Oak Gardens in out-of-court settlements to compensate for the damage caused. The mine was finally closed in December 1986.

Since 1994 AGL Resources has been using Lake Peigneur’s underlying salt dome as a Storage and Hub facility for pressurized natural gas.

There is currently concern from local residents to the safety of storing the gas under the lake and nearby drilling operations.

See also

• Lake Beloye (Nizhny Novgorod Oblast)
• Rylands v Fletcher
• Döda Fallet

References

• Gold, Michael. "Who Pulled the Plug on Lake Peigneur?", Science 81, November 1981, 56.

External links

• Oil rig disasters - Lake Peigneur
• Lake Peigneur: The biggest sinkhole ever created
• History Channel segment about Lake Peigneur
• Endangered Earth - Sinkholes Assortedde:Lake Peigneur