Effects of coastal engineering projects on sediment dispersal along Louisiana's barrier shorelines

Conference · Tue Jan 01 04:00:00 EST 1985 · Geol. Soc. Am., Abstr. Programs; (United States)

OSTI ID:6444442

Mossa, J; Penland, S; Moslow, T F

Historic maps, aerial photographs, and field data from the Mississippi River delta plain in Louisiana have shown that coastal structures can severely disrupt the sensitive sediment dispersal system of barrier shorelines with a limited sand supply. This problem has arisen because projects are designed not only to control erosion but also to aid navigation and support the oil and gas industry. The nature and magnitude of erosion-related problems varies with the type, size, and location of the structure in the barrier shoreline system. Coastal engineering projects built specifically to reduce erosion have had somewhat limited success in Louisiana. At many locations, the coastline is retreating at rates of 5 to 15 m/year. Where structures interfere with the sediment dispersal system of the barrier shoreline, rates of retreat may exceed 20 m/year. The ineffectiveness of these structures is, in part, due to natural processes, including rapid compactional subsidence and frequent storm impacts, and to a poor understanding of sediment transport processes. For example, jetties extending several hundreds of meters offshore cut off sediment transport to downdrift shorelines. Impermeable, shore-parallel structures such as revetments and seawalls prevent fair-weather, constructive processes from returning sediment removed during storms to the beach. In contrast, nonstructural measures such as repeated beach nourishment and vegetative stabilization allow longshore and onshore transport to continue. These measures have had the greatest success and hold the most promise for reducing erosion in Louisiana.

• Research Organization: Louisiana Geological Survey, University Station (USA)
• OSTI ID: 6444442
• Report Number(s): CONF-8510489-
• Conference Information: Journal Name: Geol. Soc. Am., Abstr. Programs; (United States) Journal Volume: 17
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
013000* -- Coal
Lignite
& Peat-- Transport
Handling
& Storage
02 PETROLEUM
022000 -- Petroleum-- Transport
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58 GEOSCIENCES
580100 -- Geology & Hydrology-- (-1989)
COASTAL REGIONS
CONTINENTAL MARGIN
CONTINENTAL SHELF
DEPOSITION
ENERGY SOURCES
ENGINEERING GEOLOGY
EROSION
FEDERAL REGION VI
FLUIDS
FOSSIL FUELS
FUEL GAS
FUELS
GAS FUELS
GASES
GEOLOGIC HISTORY
GEOLOGY
INDUSTRY
LOUISIANA
MARITIME TRANSPORT
NATURAL GAS
NATURAL GAS INDUSTRY
NAVIGATION
NORTH AMERICA
OFFSHORE SITES
PETROLEUM
PETROLEUM INDUSTRY
ROCKS
SAND
SANDSTONES
SEDIMENTARY ROCKS
SEDIMENTS
SHORES
TRANSPORT
USA