Cameron Parish, Louisiana
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Louisiana Department of Transportation and Development
The Holly Beach project site is located in Cameron Parish, in extreme southwestern Louisiana. The chenier ridge that supports LA Hwy 82 is the last line of defense protecting thousands of acres of intermediate marsh habitat in the Sabine National Wildlife Refuge from the Gulf of Mexico. LA Hwy 82, the only east-west road in the area, also serves as the only Hurricane evacuation route for local communities providing residents of Johnson’s Bayou, Ocean View Beach, Constance Beach and Holly Beach egress west to east and then northward on LA 27.
Shoreline erosion in this area is caused by Mississippi River channelization and Calcasieu Ship Channel jetties, limiting sediment transport availability and is accelerated by frequent storm events. Prior to the 1984 and 1988 articulating concrete block (ACB) armoring projects, shoreline erosion in the project area was occurring at rate of 24-ft. per year.
Following several unsuccessful shoreline armoring projects in 1970 and 1977, the Louisiana Department of Transportation utilized 9-in. thick Armorflex Class 70 mattresses on two subsequent projects completed in 1984 and 1988. Since completion of these two Gulf side armoring projects, the site has experienced numerous tropical storms and hurricanes during the last 20 year period, including a direct hit from Rita in 2005 and significant effects from Ike in 2008. Although the highway has sustained repeated damage on the un-armored landside during overtopping events, the Armorflex armored (Gulf ) side has performed exceptionally, preventing any significant damage to the armored (Gulf ) side of Hwy 821.
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